CodesStore { }

Add and remove elements from JavaScript array

2013-03-24T20:07:00.001+05:30

Here I show how to add ,remove elements and get a comma separated string from JavaScript array

Add / Remove elements from array

var myArray = ["Sameera","Sanath"];

//Add element to array
myArray.push("Amila");


//Check already contains and add an element
if ($.inArray("Jaya" ,myArray) == -1){
    myArray.push("Jaya");
}

console.log(myArray);


//Remove element from array

var index = $.inArray("Sanath", myArray);
myArray.splice(index, 1);

console.log(myArray);

Here I used Jquery index = $.inArray("Sanath", myArray); to get index of the element. We can also get the index by index = myArray.indexOf("Sanath"); .But indexOf does not work on IE 8 and below.

Get a comma separated string from array

//Get comma separated string from array
var myArray = ["Sameera","Sanath","Jaya"];
var myUsers = myArray.join(",");
console.log(myUsers);

Convert minutes to hours in JavaScript

2013-03-19T22:56:00.000+05:30

Convert minutes to hours in JavaScript . Eg: 400 minutes -> 06hrs 40min

<script type="text/javascript">

function convert(totalMinutes){

    var hours = leftPad(Math.floor(totalMinutes / 60));
    var minutes = leftPad(totalMinutes % 60);

    return hours +'hrs '+minutes + 'min';

}

var hrs = convert(400);

alert(hrs);            

/*
 * add zero to numbers less than 10,Eg: 2 -> 02
 */
function leftPad(number) {  
    return ((number < 10 && number >= 0) ? '0' : '') + number;
}

</script>

JavaScript Functions

2013-03-17T22:50:00.003+05:30

Here I explain different types of function creation methods in JavaScript

Create a basic function

function myFunction() {
   alert("myFunction called");
}

myFunction(); //call function

Call a function when window load

function init() {
   alert("init called");
}

window.onload = init;

Call anonymous function when window load

window.onload = function () {
   alert("anonymous function called");
};

Call a function with setTimeout

function tOut() {
   alert("tOut function called after 1000 milliseconds")
}

setTimeout(tOut, 1000);

Call anonymous function with setTimeout

setTimeout(function(){ alert("anonymous function called after 1000 milliseconds"); },1000);

Create an inner function

function outer() {

   alert("outer - before");

   function inner() {
      alert("inner");
   }

   inner(); // can call inner  here
   alert("outer - after");

}

outer();
//inner(); // cannnot call inner here

var inn;

function outer() {
   alert("outer - before");

   function inner() {
      alert("inner");

   }

   inn = inner;
   alert("outer - after");


}
outer();
inn(); // call inner here

var f = function () {
   alert("f")
};

f(); //call

var f = function myFunction() {
   alert("myFunction")
};

f();

var ob = {};
ob.func = function(){  alert("func") };
ob.func(); //call

var ob = {
    f1 : function(){ alert("f1"); },
    f2 : function(){ alert("f2"); }
} 

ob.f1(); // call

var ob = {
    f1 : function myFunction(){ alert("myFunction called"); } 
}
ob.f1(); // call

Call function using apply and call(not work on IE)

function myFunc(){
    
    for(var x in arguments){
        alert(arguments[x]);
    }

}

var o1 = {};
var o2 = {};

myFunc.apply(o1,[1,2,3]);
myFunc.call(o2,1,2,3);

Reference: Secrets of the JavaScript Ninja

JQuery

2013-03-05T22:38:00.000+05:30

Click a button/link when page load,find selected and unselected options in Jquery

Click a button when page load

$(document).ready(function () {

              $("#link").click(function () {
                 alert("link clicked");
              });

              $("#btnSearch").click(function () {
                 alert("button clicked");
              });

              $("#btnSearch").trigger('click'); // OR
              $("#btnSearch").click();


});

<input type="button" id="btnSearch" value="Search"/>

Click a hyperlink

 $('#link').click();

<a href="#" id="link" >Go</a>

Find selected and unselected options

 $(document).ready(function () {
              $("#sel").find('option:selected').css('background', "red");
              $("#sel").find('option:not(:selected)').css('background', "blue");

 });

<select id="sel" >
    <option value="USA">USA</option>
    <option value="SriLanka" selected="selected">SriLanka</option>
    <option value="India">India</option>
    <option value="Japan">Japan</option>
</select>

Remove ThreadPoolExecutor Break point in Eclipse

2013-02-16T18:42:00.002+05:30

Remove Liferay debugging breakpoints.

When I debugging my liferay portlet in Tomcat, always eclipse debugger stops at break point which was not added by me.

To disable that break point go to
Window -> Preferences -> Debug

and untick Suspend excecution on uncaught exceptions.

How to create a JavaScript Map

2013-02-16T17:27:00.003+05:30

How to create a Map in JavaScript.

I'm going to create a map with following keys and values
"mykey0" -> "myValue0"
"mykey1" -> "myValue1"
"mykey2" -> "myValue2"

map.js

var myMap = {};


//Fill map
for ( var i = 0; i < 3; i++) {
    myMap['mykey' + i] = "myValue" + i;
}

//Get map elements by key
for (key in myMap){
    alert(myMap[key]);
}

Objects sorting in java

2013-02-10T12:44:00.000+05:30

Here I explain how to sort java objects using Comparator and Comparable interfaces.

We want to sort students by marks.
Rahul: 45,
Sameera: 95,
Amith: 28,
Anju: 60,
Lahiru: 86

Method 1: Comparator

Now create student class

Student.java

package com.codestore.sorting;

/**
 * @author Sameera Jayasekara
 */
public class Student {
    String name;
    int totalMarks;

    public Student(String name, int totalMarks) {
        this.name = name;
        this.totalMarks = totalMarks;

    }

    @Override
    public String toString() {
        return name + ": " + totalMarks;
    }
}

Create comparator class and override compare method

StudentMarksComparator.java

import java.util.Comparator;

/**
 * @author Sameera Jayasekara
 */
public class StudentMarksComparator implements Comparator<Student> {

    @Override
    public int compare(Student s1, Student s2) {
        Student student1 = s1;
        Student student2 = s2;
        return student2.totalMarks - student1.totalMarks;
    }

}

Main.java

package com.codestore.sorting;

import java.util.*;

/**
 * @author Sameera Jayasekara
 */
public class Main {

    public static void main(String[] args) {

        List<Student> students = new ArrayList<Student>();
        students.add(new Student("Rahul", 45));
        students.add(new Student("Sameera", 95));
        students.add(new Student("Amith", 28));
        students.add(new Student("Anju", 60));
        students.add(new Student("Lahiru", 86));

        System.out.println("Before Sort: " + students);

        StudentMarksComparator smc = new StudentMarksComparator();
        Collections.sort(students, smc);

        System.out.println("After Sort: " + students);

    }

}

Output:
Before Sort: [Rahul: 45, Sameera: 95, Amith: 28, Anju: 60, Lahiru: 86]
After Sort: [Sameera: 95, Lahiru: 86, Anju: 60, Rahul: 45, Amith: 28]

You can directly add a comparator class as a method parameter without creating a separate class.

package com.codestore.sorting;

import java.util.*;

/**
 * @author Sameera Jayasekara
 */
public class Main {

 public static void main(String[] args) {

  List<Student> students = new ArrayList<Student>();
  students.add(new Student("Rahul", 45));
  students.add(new Student("Sameera", 95));
  students.add(new Student("Amith", 28));
  students.add(new Student("Anju", 60));
  students.add(new Student("Lahiru", 86));

  System.out.println("Before Sort: " + students);

  // StudentMarksComparator smc = new StudentMarksComparator();
  // Collections.sort(students, smc);

  Collections.sort(students, new Comparator<Student>() {

   @Override
   public int compare(Student s1, Student s2) {
    Student student1 = s1;
    Student student2 = s2;
    return student2.totalMarks - student1.totalMarks;
   }

  });

  System.out.println("After Sort: " + students);

 }

}

Method 2: Comparable

Student.java

package com.codestore.sorting.comparable;

/**
 * @author Sameera Jayasekara
 */
public class Student implements Comparable<Student> {

    String name;
    int totalMarks;

    public Student(String name, int totalMarks) {
        this.name = name;
        this.totalMarks = totalMarks;
    }

    @Override
    public int compareTo(Student s) {
        return this.totalMarks - s.totalMarks;
    }

    @Override
    public String toString() {
        return name + ": " + totalMarks;
    }

}

Main.java

package com.codestore.sorting.comparable;

import java.util.*;

/**
 * @author Sameera Jayasekara
 */
public class Main {

    public static void main(String[] args) {

        List<Student> students = new ArrayList<Student>();
        students.add(new Student("Rahul", 45));
        students.add(new Student("Sameera", 95));
        students.add(new Student("Amith", 28));
        students.add(new Student("Anju", 60));
        students.add(new Student("Lahiru", 86));

        System.out.println("Before Sort: " + students);

        Collections.sort(students);

        System.out.println("After Sort: " + students);

    }

}

Output:
Before Sort: [Rahul: 45, Sameera: 95, Amith: 28, Anju: 60, Lahiru: 86]
After Sort: [Sameera: 95, Lahiru: 86, Anju: 60, Rahul: 45, Amith: 28]

Get index of a foreach - Struts, JSTL, FreeMarker

2012-12-16T22:31:00.000+05:30

How to get the index of the current iteration of a foreach loop in Struts2, JSTL, FreeMarker

Struts 2

<s:iterator value="userList" status="status" >    
   
    <s:property value="#status.index" />
    <s:property value="firstname" />

</s:iterator>

JSTL

<c:forEach items="${userList}" var="u" varStatus="status">

    <c:out value="${status.index}" />
    <c:out value="${u.firstname}" />

</c:forEach>

FreeMarker

<#list userList as u>

    ${u_index}
    ${u.firstname}
  
</#list>

Backend code

List<User> userList = new ArrayList<User>();

userList.add(new User("sam", "jay"));
userList.add(new User("sameera", "jaya"));

Insert multiple rows MySQL

2012-12-04T23:17:00.000+05:30

You can insert multiple rows using a single query.

INSERT INTO student(first_name,last_name,username) VALUES
('sameera','jaya','samjay'),
('sanath','jaya','sanjay'),
('samal','jayaweera','samaljay');

JavaScript functions for realtime validation

2012-11-02T23:29:00.000+05:30

These are the functions you need to validate input fields.
You can add these functions to a common JavaScript file and include that to whole website.

Block users to type other characters in numeric fields.

$(document).ready(function() {    
    
    $('.numeric-only').keypress(function (e){
          if( e.which!=8 && e.which!=0 && (e.which<48 || e.which>57)){
            return false;
          }
    });

});

Usage:

 <input type="text" name="age" class="numeric-only" maxlength="3"/>

Demo:

Age:

Capitalize text when typing.

This will capitalize first letter in every word in the text field.

$(document).ready(function() {    
    
    $('.capitalize').keyup(function(evt){
        var text = $(this).val();
        $(this).val(text.replace(/^(.)|\s(.)/g, function(data){ return data.toUpperCase( ); }));
    });

});

Usage:

 <input type="text" name="fullname" class="capitalize" />

Demo:

Full Name:

Alpha only

This will only allow alpha characters when typing.

$(document).ready(function() {
    $('.alpha-only').keyup(function (e){
                  
            var text = $(this).val();
            txt=text.replace(/[^a-zA-Z]/g, '');
            $(this).val(txt);     

    });

});

Usage:

 <input type="text" name="username" class="alpha-only" />

Demo:

Username:

Alpha numeric only

This will only allow alpha and numeric characters when typing.

$(document).ready(function() {
    $('.alpha-numeric-only').keyup(function (e){
               
        var text = $(this).val();
        txt=text.replace(/[^a-zA-Z0-9]/g, '');
        $(this).val(txt);   
  
    });
});

Usage:

 <input type="text" name="displayname" class="alpha-numeric-only" />

Demo:

Display Name:

Alpha numeric space

This will only allow alpha, numeric and space characters when typing.

 $(document).ready(function() {
    $('.alpha-numeric-space').keyup(function (e){
               
        var text = $(this).val();
        txt=text.replace(/[^a-zA-Z 0-9\s]/g, '');
        $(this).val(txt);   
  
    });
});

Usage:

 <input type="text" name="nickname" class="alpha-numeric-space" />

Demo:

Nickname:

How to disable autocomplete

2012-11-02T23:06:00.000+05:30

You can disable auto complete using this code.
Put these code to your common JavaScript file. This code will add autocomplete= "off" to all inputs or forms in your website.You don't want to add all html inputs or forms manually. So it wiil be easy for you.

$(document).ready(function() {

    $('input').attr('autocomplete', 'off');

});

$(document).ready(function() {

    $('form').attr('autocomplete', 'off');

});

How to create a Java application with Maven

2012-07-05T17:10:00.001+05:30

Here I explain how to create and run Java Application using Maven and Eclipse.
Tools used

Eclipse (Helios)
Maven Integration for Eclipse (Help->Eclipse Marketplace and install it.)
Exec Maven Plugin

Create new Maven project.

Now generated project structure look like this.

Generated pom.xml

pom.xml

<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
  xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
  <modelVersion>4.0.0</modelVersion>

  <groupId>codesstore</groupId>
  <artifactId>codesstore-core</artifactId>
  <version>0.0.1-SNAPSHOT</version>
  <packaging>jar</packaging>

  <name>codesstore-core</name>
  <url>http://maven.apache.org</url>

  <properties>
    <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
  </properties>

  <dependencies>
    <dependency>
      <groupId>junit</groupId>
      <artifactId>junit</artifactId>
      <version>3.8.1</version>
      <scope>test</scope>
    </dependency>
  </dependencies>
</project>

I created a new class called MyClass.java in com.codesstore.util package.

MyClass.java

package com.codesstore.util;

public class MyClass {

 public void printHello() {
  System.out.println("Hello Maven...");
 }
}

And called that class in main method.

App.java

package com.codesstore.main;

import com.codesstore.util.MyClass;


public class App {
 
 public static void main(String[] args) {
  new MyClass().printHello();
 }
}

Now I'm going to add Exec plugin to pom.xml. See more information on Exec plugin http://mojo.codehaus.org/exec-maven-plugin/

pom.xml

<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
 xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
 <modelVersion>4.0.0</modelVersion>

 <groupId>codesstore</groupId>
 <artifactId>codesstore-core</artifactId>
 <version>0.0.1-SNAPSHOT</version>
 <packaging>jar</packaging>

 <name>codesstore-core</name>
 <url>http://maven.apache.org</url>

 <properties>
  <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
 </properties>

 <dependencies>
  <dependency>
   <groupId>junit</groupId>
   <artifactId>junit</artifactId>
   <version>3.8.1</version>
   <scope>test</scope>
  </dependency>
 </dependencies>

 <build>
  <plugins>
   <plugin>
    <groupId>org.codehaus.mojo</groupId>
    <artifactId>exec-maven-plugin</artifactId>
    <version>1.1-beta-1</version>
    <executions>
     <execution>
      <goals>
       <goal>java</goal>
      </goals>
     </execution>
    </executions>
    <configuration>
     <mainClass>com.codesstore.main.App</mainClass>
    </configuration>
   </plugin>
  </plugins>
 </build>

</project>

Right click on the pom file -> Run as ->Maven build..

Then you can set goals to run. I use exec:java here.

Out put

Project structure in Eclipse

EJB3 and JPA step by step tutorial using NetBeans

2012-07-05T11:35:00.000+05:30

Here I explain step by step how to create an EJB 3 with JPA application in NetBeans IDE.
This tutorial is for beginners who want to learn steps to create EJB persistence application with NetBeans and Glassfish.

Tools used

NetBeans 6.9.1
Glassfish Server 3
MySQL database

Create an Enterprise Application called StudentManagementEA.

Click on images to enlarge

It creates web module and EJB modules.

Now create a database called studentmgt_db. Go to services tab and create it.

Again go to Projects tab and create Persistence Unit. It will generate the persistence.xml file.

Give a JNDI name and select data base you created.

It will generate an XML file called persistence.xml

<?xml version="1.0" encoding="UTF-8"?>
<persistence version="2.0" xmlns="http://java.sun.com/xml/ns/persistence" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://java.sun.com/xml/ns/persistence http://java.sun.com/xml/ns/persistence/persistence_2_0.xsd">
  <persistence-unit name="StudentManagementEA-ejbPU" transaction-type="JTA">
    <provider>org.eclipse.persistence.jpa.PersistenceProvider</provider>
    <jta-data-source>jdbc/studentmgt</jta-data-source>
    <exclude-unlisted-classes>false</exclude-unlisted-classes>
    <properties>
      <property name="eclipselink.ddl-generation" value="create-tables"/>
    </properties>
  </persistence-unit>
</persistence>

Then we have to create an Entity class.

Entity Class must have @Entity annotaion
Must have a public or protected no-arg constructor
If it passed as a detached object through a remote interface, Must implement Serializable
Must have an id annotated with @Id

I created a new java class called Student.java

package com.sameera.domain;

import java.io.Serializable;
import javax.persistence.*;

@Entity
@Table(name = "student")
public class Student implements Serializable {

    @Id
    @GeneratedValue
    @Column(name = "id")
    private Integer id;
    @Column(name = "first_name", length = 100)
    private String firstName;
    @Column(name = "last_name", length = 100)
    private String lastName;
    @Column(name = "email", length = 100)
    private String email;

    public String getEmail() {
        return email;
    }

    public void setEmail(String email) {
        this.email = email;
    }

    public String getFirstName() {
        return firstName;
    }

    public void setFirstName(String firstName) {
        this.firstName = firstName;
    }

    public Integer getId() {
        return id;
    }

    public void setId(Integer id) {
        this.id = id;
    }

    public String getLastName() {
        return lastName;
    }

    public void setLastName(String lastName) {
        this.lastName = lastName;
    }
}

Create session beans.

I create a Stateless session bean with Local interface.

It will generate ManageStudentSessionBean.java and ManageStudentSessionBeanLocal.java files.Then we can add business methods.Insert Code -> Add Business Method

Give method name parameters and return types.

ManageStudentSessionBeanLocal.java

package com.sameera.session;

import com.sameera.domain.Student;
import javax.ejb.Local;

/**
 *
 * @author Sameera Jayasekara
 */
@Local
public interface ManageStudentSessionBeanLocal {

    boolean addStudent(Student student);
    
}

ManageStudentSessionBean.java

package com.sameera.session;

import com.sameera.domain.Student;
import javax.ejb.Stateless;
import javax.persistence.EntityManager;
import javax.persistence.PersistenceContext;

/**
 *
 * @author Sameera Jayasekara
 */
@Stateless
public class ManageStudentSessionBean implements ManageStudentSessionBeanLocal {

    @PersistenceContext
    private EntityManager entityManager;

    public boolean addStudent(Student student) {

        entityManager.persist(student);

        return true;
    }
}

I didn't do exception handling and other stuff. Just added simple persist code and returned true.

Now you can deploy EJB module.

Now go to database view and see generated tables.

Now start working on web module.
In index file I created a form to fill data of a student and submit to ManageStudentServlet. Add this code to index.jsp

<%@page contentType="text/html" pageEncoding="UTF-8"%>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"
    "http://www.w3.org/TR/html4/loose.dtd">

<html>
    <head>
        <meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
        <title>EJB3 JPA Glassfish - codesstore.blogspot.com</title>
    </head>
    <body>

        <form action="ManageStudentServlet" method="POST">

            <table border="0" width="100%">
                <tr>
                    <td colspan="3">  ${message}</td>
                </tr>
                <tr>
                    <td>First Name</td>
                    <td>:</td>
                    <td><input type="text" name="fname" value="" /></td>
                </tr>
                <tr>
                    <td>Last Name</td>
                    <td>:</td>
                    <td><input type="text" name="lname" value="" /></td>
                </tr>
                <tr>
                    <td>Email</td>
                    <td>:</td>
                    <td><input type="text" name="email" value="" /></td>
                </tr>
                <tr>
                    <td></td>
                    <td></td>
                    <td><input type="submit" value="Add" name="Add" /></td>
                </tr>
            </table>

        </form>

    </body>
</html>

Create a servlet to handle the request.

I gave the name ManageStudentServlet

Call to session beans in EJB module using dependancy injection
Insert Code -> Call Enterprise Bean

Select ManageStudentSessionBean from list.

ManageStudentServlet.java

package com.sameera.controller;

import com.sameera.domain.Student;
import com.sameera.session.ManageStudentSessionBeanLocal;

import java.io.IOException;
import java.io.PrintWriter;
import javax.ejb.EJB;
import javax.servlet.RequestDispatcher;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;


/**
 *
 * @author Sameera Jayasekara
 */

public class ManageStudentServlet extends HttpServlet {

    @EJB
    private ManageStudentSessionBeanLocal manageStudentSessionBean;


    protected void processRequest(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {

        response.setContentType("text/html;charset=UTF-8");
        PrintWriter out = response.getWriter();
        String message = "";

        String firstName = request.getParameter("fname");
        String lastName = request.getParameter("lname");
        String email = request.getParameter("email");

        Student student = new Student();
        student.setFirstName(firstName);
        student.setLastName(lastName);
        student.setEmail(email);
       
        if (manageStudentSessionBean.addStudent(student)) {
            message = "Student Successfuly Added";
        } else {
            message = "Student Adding Failed";
        }

        request.setAttribute("message", message);
        RequestDispatcher rd = request.getRequestDispatcher("index.jsp");
        rd.forward(request, response);

    }

    @Override
    protected void doGet(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {
        processRequest(request, response);
    }

    @Override
    protected void doPost(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {
        processRequest(request, response);
    }

    @Override
    public String getServletInfo() {
        return "Short description";
    }

}

web.xml configuration file looks like this.

<?xml version="1.0" encoding="UTF-8"?>
<web-app version="2.5" xmlns="http://java.sun.com/xml/ns/javaee" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd">
    <servlet>
        <servlet-name>ManageStudentServlet</servlet-name>
        <servlet-class>com.sameera.controller.ManageStudentServlet</servlet-class>
    </servlet>

    <servlet-mapping>
        <servlet-name>ManageStudentServlet</servlet-name>
        <url-pattern>/ManageStudentServlet</url-pattern>
    </servlet-mapping>

    <session-config>
        <session-timeout>
            30
        </session-timeout>
    </session-config>

    <welcome-file-list>
        <welcome-file>index.jsp</welcome-file>
    </welcome-file-list>

</web-app>

Now deploy the web module and run EnterpriseApplication.
Check the database data will be added.

Note: I added MySQL connector mysql-connector-java-5.1.6-bin.jar to .../GF3/domain1/lib folder in glassfish.Goto services tab and right click on glassfish -> properties find glassfish domain folder.

EJB3 and JPA step by step tutorial using Eclipse

2012-07-05T09:41:00.000+05:30

Here I explain step by step how to create an EJB 3 with JPA application in Eclipse IDE.
This tutorial is for beginners who want to learn steps to create EJB persistence application with Eclipse and Jboss.

Tools used

Eclipse (Galileo)
Jboss-5.1.0.GA
MySQL database

First of all I'll create a database called studentmgt_db. You can use MySQL GUI tool like MySQL Query Browser or MySQL Work Bench to create a database.

Then I'm going to create a datasource. Go to your jboss directory ..jboss-5.1.0.GA\docs\examples\jca inside that folder there is file called mysql-ds.xml. I copied that file to ...jboss-5.1.0.GA\server\default\deploy. Then you can add your database details to that file.

mysql-ds.xml

<?xml version="1.0" encoding="UTF-8"?>

<!-- $Id: mysql-ds.xml 41017 2006-02-07 14:26:14Z acoliver $ -->
<!--  Datasource config for MySQL using 3.0.9 available from:
http://www.mysql.com/downloads/api-jdbc-stable.html
-->

<datasources>
  <local-tx-datasource>
    <jndi-name>StudentMgtDS</jndi-name>
    <connection-url>jdbc:mysql://localhost:3306/studentmgt_db</connection-url>
    <driver-class>com.mysql.jdbc.Driver</driver-class>
    <user-name>root</user-name>
    <password>123</password>
    <exception-sorter-class-name>org.jboss.resource.adapter.jdbc.vendor.MySQLExceptionSorter</exception-sorter-class-name>
    <!-- should only be used on drivers after 3.22.1 with "ping" support
    <valid-connection-checker-class-name>org.jboss.resource.adapter.jdbc.vendor.MySQLValidConnectionChecker</valid-connection-checker-class-name>
    -->
    <!-- sql to call when connection is created
    <new-connection-sql>some arbitrary sql</new-connection-sql>
      -->
    <!-- sql to call on an existing pooled connection when it is obtained from pool - MySQLValidConnectionChecker is preferred for newer drivers
    <check-valid-connection-sql>some arbitrary sql</check-valid-connection-sql>
      -->

    <!-- corresponding type-mapping in the standardjbosscmp-jdbc.xml (optional) -->
    <metadata>
       <type-mapping>mySQL</type-mapping>
    </metadata>
  </local-tx-datasource>
</datasources>

Now create EJB project.

Create a new EJB project called StudentManagementEJB. I use JBoss server as application server.

Create a xml file called persistence.xml in META-INF directory.

persistence.xml

<?xml version="1.0" encoding="UTF-8"?>
<persistence version="2.0"
 xmlns="http://java.sun.com/xml/ns/persistence" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
 xsi:schemaLocation="http://java.sun.com/xml/ns/persistence http://java.sun.com/xml/ns/persistence/persistence_2_0.xsd">
 <persistence-unit name="StudentMgtPU"
  transaction-type="JTA">
  <jta-data-source>java:/StudentMgtDS</jta-data-source>
  <properties>
   <property name="hibernate.dialect" value="org.hibernate.dialect.MySQLDialect" />
   <property name="hibernate.hbm2ddl.auto" value="create" />
  </properties>
 </persistence-unit>
</persistence>

Then we have to create an Entity class. Right click on the project -> New -> Class

Entity Class must have @Entity annotaion
Must have a public or protected no-arg constructor
If it passed as a detached object through a remote interface, Must implement Serializable
Must have an id annotated with @Id

I created a entity class called Student.java

Student.java

package com.sameera.domain;

import java.io.Serializable;
import javax.persistence.*;

@Entity
@Table(name = "student")
public class Student implements Serializable {

    private static final long serialVersionUID = 1L;

    @Id
    @GeneratedValue
    @Column(name = "id")
    private Integer id;
    @Column(name = "first_name", length = 100)
    private String firstName;
    @Column(name = "last_name", length = 100)
    private String lastName;
    @Column(name = "email", length = 100)
    private String email;

    public String getEmail() {
        return email;
    }

    public void setEmail(String email) {
        this.email = email;
    }

    public String getFirstName() {
        return firstName;
    }

    public void setFirstName(String firstName) {
        this.firstName = firstName;
    }

    public Integer getId() {
        return id;
    }

    public void setId(Integer id) {
        this.id = id;
    }

    public String getLastName() {
        return lastName;
    }

    public void setLastName(String lastName) {
        this.lastName = lastName;
    }
}

Create session beans.

I create a Stateless session bean with Local interface.

I added business methods and added add student code.

ManageStudentSessionBeanLocal.java

package com.sameera.session;

import javax.ejb.Local;

import com.sameera.domain.Student;

/**
 * 
 * @author Sameera Jayasekara
 * 
 */
@Local
public interface ManageStudentSessionBeanLocal {
 public boolean addStudent(Student Student);
}

ManageStudentSessionBean.java

package com.sameera.session;

import javax.ejb.Stateless;
import javax.persistence.EntityManager;
import javax.persistence.PersistenceContext;

import com.sameera.domain.Student;

/**
 * Session Bean implementation class ManageStudentSessionBean
 * 
 * @author Sameera Jayasekara
 */
@Stateless
public class ManageStudentSessionBean implements ManageStudentSessionBeanLocal {

 @PersistenceContext
 private EntityManager entityManager;

 @Override
 public boolean addStudent(Student student) {
  entityManager.persist(student);
  return true;
 }

}

Run EJB application on Jboss server.

See the server console JNDI bindings.

Now see the database. Student table is created.

Now start working on web application.
File -> New -> Dynamic Web Project

Go next Select 'Generate web.xml deployment descriptor' and finish.

Right click on web content and create a new jsp called index.jsp.

index.jsp

<%@page contentType="text/html" pageEncoding="UTF-8"%>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"
    "http://www.w3.org/TR/html4/loose.dtd">

<html>
    <head>
        <meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
        <title>EJB3 JPA Jboss - codesstore.blogspot.com</title>
    </head>
    <body>

        <form action="ManageStudentServlet" method="POST">

            <table border="0" width="100%">
                <tr>
                    <td colspan="3">  ${message}</td>
                </tr>
                <tr>
                    <td>First Name</td>
                    <td>:</td>
                    <td><input type="text" name="fname" value="" /></td>
                </tr>
                <tr>
                    <td>Last Name</td>
                    <td>:</td>
                    <td><input type="text" name="lname" value="" /></td>
                </tr>
                <tr>
                    <td>Email</td>
                    <td>:</td>
                    <td><input type="text" name="email" value="" /></td>
                </tr>
                <tr>
                    <td></td>
                    <td></td>
                    <td><input type="submit" value="Add" name="Add" /></td>
                </tr>
            </table>

        </form>

    </body>
</html>

Create a servlet to handle the request.
File -> New -> Servlet

Before calling Enterprise beans we have to add the ejb project to build path.

Go to projects tab and add StudentManagementEJB project.

ManageStudentServlet.java

package com.sameera.controller;

import java.io.IOException;

import javax.naming.Context;
import javax.naming.InitialContext;
import javax.naming.NamingException;
import javax.servlet.RequestDispatcher;
import javax.servlet.ServletConfig;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import com.sameera.domain.Student;
import com.sameera.session.ManageStudentSessionBeanLocal;

/**
 * 
 * @author Sameera Jayasekara
 * 
 */
public class ManageStudentServlet extends HttpServlet {

 private static final long serialVersionUID = 1L;
 private ManageStudentSessionBeanLocal manageStudentSessionBeanLocal;

 public void init(ServletConfig config) throws ServletException {

  super.init(config);
  try {

   Context context = new InitialContext();
   manageStudentSessionBeanLocal = (ManageStudentSessionBeanLocal) context
     .lookup("ManageStudentSessionBean/local");

  } catch (NamingException e) {
   e.printStackTrace();
  }

 }

 protected void doGet(HttpServletRequest request,
   HttpServletResponse response) throws ServletException, IOException {

 }

 protected void doPost(HttpServletRequest request,
   HttpServletResponse response) throws ServletException, IOException {

  String message = "";

  String firstName = request.getParameter("fname");
  String lastName = request.getParameter("lname");
  String email = request.getParameter("email");

  Student student = new Student();
  student.setFirstName(firstName);
  student.setLastName(lastName);
  student.setEmail(email);

  if (manageStudentSessionBeanLocal.addStudent(student)) {
   message = "Student Successfuly Added";
  } else {
   message = "Student Adding Failed";
  }

  request.setAttribute("message", message);
  RequestDispatcher rd = request.getRequestDispatcher("index.jsp");
  rd.forward(request, response);

 }

}

I looked up ManageStudentSessionBean/local. You can see server console to find JNDI bindings(see image given above)

You can use @EJB annotaions to dependancy injection in a servlet but I tried it with JBoss that didn't work.Then I used @EJB(mappedName="Test"), @EJB with mappedName attribute( @Stateless(mappedName="Test") also used).Then it worked with remote interface. But I prefer JNDI lookup.

web.xml configuration file looks like this.

web.xml

<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://java.sun.com/xml/ns/javaee" xmlns:web="http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd" xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd" id="WebApp_ID" version="2.5">
  <display-name>StudentManagementWeb</display-name>
  <welcome-file-list>
    <welcome-file>index.jsp</welcome-file>
  </welcome-file-list>
  <servlet>
    <description></description>
    <display-name>ManageStudentServlet</display-name>
    <servlet-name>ManageStudentServlet</servlet-name>
    <servlet-class>com.sameera.controller.ManageStudentServlet</servlet-class>
  </servlet>
  <servlet-mapping>
    <servlet-name>ManageStudentServlet</servlet-name>
    <url-pattern>/ManageStudentServlet</url-pattern>
  </servlet-mapping>
</web-app>

Now You can run the web application.

Check the database data will be added.

Project structure in Eclipse

Note : I put mysql-connector-java-5.1.5-bin.jar to ...jboss-5.1.0.GA\server\default\lib

MySQL CASE WHEN IF

2012-04-10T13:31:00.002+05:30

MySQL CASE WHEN statements and IF statement example.

CREATE TABLE student (
    id int(11) NOT NULL AUTO_INCREMENT,
    name varchar(100) NOT NULL,
    marks int(11) NOT NULL,
    course_type varchar(2) NOT NULL,
    PRIMARY KEY (`id`)
) ENGINE=InnoDB AUTO_INCREMENT=1 DEFAULT CHARSET=latin1;

SELECT name, marks, CASE
                       WHEN marks>75 THEN 'A'
                       WHEN marks>65 THEN 'B'
                       WHEN marks>50 THEN 'C'
                       ELSE  'F'
                    END
                    AS results 
FROM student ORDER BY name

SELECT name,course_type,
       CASE course_type
         WHEN 'WE' THEN 'Week End'
         WHEN 'WD' THEN 'Week Days'
       END AS course
FROM student ORDER BY name

SELECT name, marks, IF(marks >= 50,'PASS','FAIL') AS result
FROM student
ORDER BY name

MySQL Database Dump

2012-04-05T23:24:00.006+05:30

MySQL Database Dump using Command prompt.
Get a backup
command :
mysqldump -u[user name] -p[password] [database name] > [dump file name]

eg :
C:\Documents and Settings\sameera>mysqldump -u root -p mydb>"C:\Documents and Settings\sameera\Desktop\mydumpfile.sql"

Restore Back up
1)
command :
mysql -u[user name] -p[password] [database name] < [dump file name]

eg :

C:\Documents and Settings\sameera>mysql -u root -p mydb < "C:\Documents and Settings\sameera\Desktop\mydumpfile.sql"

2)
command :
source [dump file name]

eg:
mysql>create database mydb;
mysql> use mydb
mysql> source C:/Documents and Settings/sameera/Desktop/mydumpfile.sql;

Note: Path separator should be forward slash("/")

Stored Procedures with JAVA

2012-02-04T00:42:00.000+05:30

Stored Procedures with JAVA using MySQL

add_student

For an example I added username ,first name and last name to student table and get auto incremented primay key id and save email and telephone to student_contact table.

DELIMITER $$

CREATE DEFINER=`root`@`localhost` PROCEDURE `add_student`(p_username varchar(20),p_firstname varchar(20),p_lastname  varchar(20),p_email varchar(20),p_telephone varchar(20))
BEGIN
    DECLARE stu_id int(11);
    START TRANSACTION;
        INSERT INTO student(username,first_name,last_name)
        VALUES(p_username,p_firstname,p_lastname);
        SELECT id FROM student WHERE username=p_username INTO stu_id;
        INSERT INTO student_contact(stu_id,email,telephone) VALUES(stu_id,p_email,p_telephone);
    COMMIT;

END

search_students

This sp returns student records.

DELIMITER $$

CREATE DEFINER=`root`@`localhost` PROCEDURE `search_students`(p_first_name varchar(20))
BEGIN
     SELECT * FROM student WHERE first_name LIKE concat(p_first_name,'%');
END

get_firstname_by_username

This sp uses input parameter and out put parameter

DELIMITER $$

CREATE DEFINER=`root`@`localhost` PROCEDURE `get_firstname_by_username`(p_username varchar(20),OUT p_firstname varchar(20))
SELECT first_name INTO p_firstname
FROM student
WHERE username = p_username

StudentDAO.java

call stored procedures.

package codesstore.dao;

import java.sql.CallableStatement;
import java.sql.Connection;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.util.ArrayList;
import java.util.List;

import codesstore.db.JDBCConnector;
import codesstore.domain.Student;

public class StudentDAO {
    public void addStudent(Student student) {
        try {
            Connection con = JDBCConnector.getConnection();
            CallableStatement proc = con
                    .prepareCall("{ call add_student(?, ?, ?, ?, ?) }");
            proc.setString(1, student.getUsername());
            proc.setString(2, student.getFirstName());
            proc.setString(3, student.getLastName());
            proc.setString(4, student.getEmail());
            proc.setString(5, student.getTelephone());
            proc.execute();
        } catch (SQLException e) {
            e.printStackTrace();
        }
    }

    public List<Student> searchStudents(String firstName) {
        List<Student> students = new ArrayList<Student>();
        try {
            Connection con = JDBCConnector.getConnection();
            CallableStatement proc = con
                    .prepareCall("{ call search_students(?) }");

            proc.setString(1, firstName);
            proc.execute();
            ResultSet rs = proc.getResultSet();
            while (rs.next()) {
                Student s = new Student();
                s.setFirstName(rs.getString("first_name"));
                s.setLastName(rs.getString("last_name"));
                s.setUsername(rs.getString("username"));
                students.add(s);
            }

        } catch (SQLException e) {
            e.printStackTrace();
        }
        return students;
    }

    public String getFirstNameByUsername(String username) {
        String firstName = null;
        try {
            Connection con = JDBCConnector.getConnection();
            CallableStatement proc = con
                    .prepareCall("{ call get_firstname_by_username(?,?) }");

            proc.setString(1, username);
            proc.registerOutParameter(2, java.sql.Types.VARCHAR);
            proc.execute();
            firstName = proc.getString(2);

        } catch (SQLException e) {
            e.printStackTrace();
        }

        return firstName;
    }

}

Other files

web.xml

<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xmlns="http://java.sun.com/xml/ns/javaee" xmlns:web="http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd"
    xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd"
    id="WebApp_ID" version="2.5">
    <display-name>SPtesting</display-name>
    <welcome-file-list>
        <welcome-file>index.jsp</welcome-file>
    </welcome-file-list>
    <servlet>
        <description></description>
        <display-name>StudentServlet</display-name>
        <servlet-name>StudentServlet</servlet-name>
        <servlet-class>codesstore.controller.StudentServlet</servlet-class>
    </servlet>
    <servlet-mapping>
        <servlet-name>StudentServlet</servlet-name>
        <url-pattern>/StudentServlet</url-pattern>
    </servlet-mapping>
</web-app>

index.php

<%@ page language="java" contentType="text/html; charset=ISO-8859-1"
    pageEncoding="ISO-8859-1"%>
<%@taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core" %>    
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1">
<title>Stored Procedure - codesstore.blogspot.com</title>
</head>
<body>
    <form action="StudentServlet" method="post">
        <table>
            <tr>
                <td colspan="2">Personal details    </td>
            </tr>
            <tr>
                <td>Username</td>
                <td><input name="username" type="text"/></td>
            </tr>
            <tr>
                <td>First Name</td>
                <td><input name="fname" type="text"/></td>
            </tr>
            <tr>
                <td>Last Name</td>
                <td><input name="lname" type="text"/></td>
            </tr>
            <tr>
                <td colspan="2">Contact details    </td>
            </tr>
            <tr>
                <td>Email</td>
                <td><input name="email" type="text"/></td>
            </tr>
            <tr>
                <td>Telephone</td>
                <td><input name="telephone" type="text"/></td>
            </tr>
            <tr>
                <td></td>
                <td><input type="submit" value="Add" name="action"> </td>
            </tr>
        </table>
    </form>
    Search by First name
    <form action="StudentServlet" method="post">
        <input name="fname" type="text"/>
        <input type="submit" value="Search" name="action"> 
    </form>
    Get first name by Username
    <form action="StudentServlet" method="post">
        <input name="username" type="text"/>
        <input type="submit" value="GetFirstName" name="action" > 
    </form>
    
    <c:forEach items="${students}" var="student">
        ${student.username}
        ${student.firstName}
        ${student.lastName}
        <br/>
    </c:forEach>

    <c:if test="${firstName != null}">
        ${firstName}
    </c:if>
    
    
</body>
</html>

StudentServlet.java

package codesstore.controller;

import java.io.IOException;
import java.util.List;

import javax.servlet.RequestDispatcher;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import codesstore.dao.StudentDAO;
import codesstore.domain.Student;

public class StudentServlet extends HttpServlet {
    private static final long serialVersionUID = 1L;

    public StudentServlet() {
        super();

    }

    protected void doGet(HttpServletRequest request,
            HttpServletResponse response) throws ServletException, IOException {

    }

    protected void doPost(HttpServletRequest request,
            HttpServletResponse response) throws ServletException, IOException {
        String action = request.getParameter("action");
        if (action != null && action.equals("Search")) {
            
            String firstName = request.getParameter("fname");
            StudentDAO studentDAO = new StudentDAO();
            List<Student> students = studentDAO.searchStudents(firstName);
            request.setAttribute("students", students);
            RequestDispatcher rd = request.getRequestDispatcher("index.jsp");
            rd.forward(request, response);
        
        } else if (action != null && action.equals("GetFirstName")) {
            
            String username = request.getParameter("username");
            StudentDAO studentDAO = new StudentDAO();
            String firstName = studentDAO.getFirstNameByUsername(username);
            
            request.setAttribute("firstName", firstName);
            RequestDispatcher rd = request.getRequestDispatcher("index.jsp");
            rd.forward(request, response);

        } else if (action != null && action.equals("Add")) {

            String userName = request.getParameter("username");
            String firstName = request.getParameter("fname");
            String lastName = request.getParameter("lname");
            String email = request.getParameter("email");
            String telephone = request.getParameter("telephone");

            Student student = new Student();
            student.setUsername(userName);
            student.setFirstName(firstName);
            student.setLastName(lastName);
            student.setEmail(email);
            student.setTelephone(telephone);

            StudentDAO studentDAO = new StudentDAO();
            studentDAO.addStudent(student);
            
            RequestDispatcher rd = request.getRequestDispatcher("index.jsp");
            rd.forward(request, response);
            
        }

    }

}

Student.java

package codesstore.domain;

public class Student {
    String username;
    String firstName;
    String lastName;
    String email;
    String telephone;

    public String getUsername() {
        return username;
    }

    public void setUsername(String username) {
        this.username = username;
    }

    public String getFirstName() {
        return firstName;
    }

    public void setFirstName(String firstName) {
        this.firstName = firstName;
    }

    public String getLastName() {
        return lastName;
    }

    public void setLastName(String lastName) {
        this.lastName = lastName;
    }

    public String getEmail() {
        return email;
    }

    public void setEmail(String email) {
        this.email = email;
    }

    public String getTelephone() {
        return telephone;
    }

    public void setTelephone(String telephone) {
        this.telephone = telephone;
    }

}

JDBCConnector.java

package codesstore.db;

import java.sql.Connection;
import java.sql.DriverManager;
import java.util.logging.Level;
import java.util.logging.Logger;

public class JDBCConnector {
    private static Connection con;
    public static Connection getConnection() {
        if (con == null) {
            try {
                Class.forName("com.mysql.jdbc.Driver");
                con = DriverManager.
                        getConnection("jdbc:mysql://localhost:3306/mydbsp", "root", "123");
            } catch (Exception ex) {
                Logger.getLogger(JDBCConnector.class.getName()).log(Level.SEVERE, null, ex);
            }
        }
        return con;
    }
}

sql tables

CREATE TABLE `student` (
  `id` int(11) NOT NULL AUTO_INCREMENT,
  `first_name` varchar(45) DEFAULT NULL,
  `last_name` varchar(45) DEFAULT NULL,
  `username` varchar(45) NOT NULL,
  PRIMARY KEY (`id`),
  UNIQUE KEY `username` (`username`)
) ENGINE=InnoDB AUTO_INCREMENT=16 DEFAULT CHARSET=latin1;

CREATE TABLE `student_contact` (
  `stu_id` int(11) NOT NULL,
  `email` varchar(20) DEFAULT NULL,
  `telephone` varchar(20) DEFAULT NULL,
  PRIMARY KEY (`stu_id`),
  CONSTRAINT `FK_student_personal_1` FOREIGN KEY (`stu_id`) REFERENCES `student` (`id`) ON DELETE CASCADE ON UPDATE CASCADE
) ENGINE=InnoDB DEFAULT CHARSET=latin1;

File structure in eclipse.

Struts 2 + Hibernate

2012-01-22T23:30:00.000+05:30

Struts2 Hibernate integration example..

Tools
Eclipse IDE
Jboss 5

Create a dynamic web project in eclipse and add following files.

web.xml

<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://java.sun.com/xml/ns/javaee" xmlns:web="http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd" xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd" id="WebApp_ID" version="2.5">
  <display-name>StrutsHibernate</display-name>
  <filter>
    <filter-name>struts2</filter-name>
    <filter-class>org.apache.struts2.dispatcher.FilterDispatcher</filter-class>
  </filter>
  <filter-mapping>
    <filter-name>struts2</filter-name>
    <url-pattern>/*</url-pattern>
  </filter-mapping>
  <welcome-file-list>
    <welcome-file>index.jsp</welcome-file>
  </welcome-file-list>
</web-app>

hibernate.cfg.xml

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE hibernate-configuration PUBLIC "-//Hibernate/Hibernate Configuration DTD 3.0//EN" "http://hibernate.sourceforge.net/hibernate-configuration-3.0.dtd">
<hibernate-configuration>
    <session-factory>
        <property name="hibernate.dialect">org.hibernate.dialect.MySQLDialect</property>
        <property name="hibernate.connection.driver_class">com.mysql.jdbc.Driver</property>
        <property name="hibernate.connection.url">jdbc:mysql://localhost:3306/mydb</property>
        <property name="hibernate.connection.username">root</property>
        <property name="hibernate.connection.password">123</property>
        <mapping class="codesstore.strutshibernate.domain.Student" />
    </session-factory>
</hibernate-configuration>

<!-- for oracle -->
<!--  
<hibernate-configuration>
    <session-factory>
        <property name="hibernate.dialect">org.hibernate.dialect.OracleDialect</property>
        <property name="hibernate.connection.driver_class">oracle.jdbc.driver.OracleDriver</property>
        <property name="hibernate.connection.url">jdbc:oracle:thin:@localhost:1521:mydb</property>
        <property name="hibernate.connection.username">scott</property>
        <property name="hibernate.connection.password">tiger</property>
        <mapping class="codesstore.strutshibernate.domain.Student" />
    </session-factory>
</hibernate-configuration>
-->

struts.xml

<!DOCTYPE struts PUBLIC
"-//Apache Software Foundation//DTD Struts Configuration 2.0//EN"
"http://struts.apache.org/dtds/struts-2.0.dtd">

<struts>
    <!-- Configuration for the default package. -->
    <package name="default" extends="struts-default">
        <action name="addStudent" class="codesstore.strutshibernate.action.StudentAction"
            method="addStudent">
            <result name="success">student.jsp</result>
            <result name="input">student.jsp</result>
        </action>
        <action name="listStudents" class="codesstore.strutshibernate.action.StudentAction"
            method="listStudents">
            <result name="success">student.jsp</result>
            <result name="input">student.jsp</result>
        </action>
    </package>
</struts>

HibernateUtil.java

package codesstore.strutshibernate.util;

import org.hibernate.SessionFactory;
import org.hibernate.cfg.AnnotationConfiguration;


public class HibernateUtil {

    private static final SessionFactory sessionFactory;

    static {
        try {
            sessionFactory = new AnnotationConfiguration().configure().buildSessionFactory();
        } catch (Exception ex) {
            ex.printStackTrace();
            throw new ExceptionInInitializerError();
        }
    }

    public static SessionFactory getSessionFactory() {
        return sessionFactory;
    }
}

Student.java

package codesstore.strutshibernate.domain;

import java.io.Serializable;
import java.util.Date;

import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.GenerationType;
import javax.persistence.Id;
import javax.persistence.Table;
import javax.persistence.Temporal;
import javax.persistence.TemporalType;

@Entity
@Table(name = "STUDENT")
public class Student implements Serializable {

    @Id
    @GeneratedValue(strategy = GenerationType.AUTO)
    @Column(name = "ID")
    private Integer id;
    @Column(name = "NAME", length = 100)
    private String username;
    @Column(name = "EMAIL", length = 100)
    private String email;
    @Column(name="ADDED_TIME")
    @Temporal(TemporalType.DATE)
    private Date addedTime;

    public String getEmail() {
        return email;
    }

    public void setEmail(String email) {
        this.email = email;
    }

    public Date getAddedTime() {
        return addedTime;
    }

    public void setAddedTime(Date addedTime) {
        this.addedTime = addedTime;
    }

    public Integer getId() {
        return id;
    }

    public void setId(Integer id) {
        this.id = id;
    }

    public String getUsername() {
        return username;
    }

    public void setUsername(String username) {
        this.username = username;
    }

}

StudentDao.java

package codesstore.strutshibernate.dao;

import java.util.List;

import codesstore.strutshibernate.domain.Student;

public interface StudentDao {
    public boolean saveStudent(Student student);
    public List<Student> listStudents();
}

StudentDaoImpl.java

package codesstore.strutshibernate.dao;

import java.util.List;

import org.hibernate.Query;
import org.hibernate.Session;
import org.hibernate.Transaction;

import codesstore.strutshibernate.domain.Student;
import codesstore.strutshibernate.util.HibernateUtil;

public class StudentDaoImpl implements StudentDao {

    @Override
    public boolean saveStudent(Student student) {

        Session session = null;
        Transaction transaction = null;
        try {
            session = HibernateUtil.getSessionFactory().openSession();
            transaction = session.beginTransaction();
            session.save(student);
            transaction.commit();
            return true;
        } catch (Exception e) {
            if (transaction != null) {
                transaction.rollback();
            }
            return false;
        } finally {
            if (session != null) {
                session.close();
            }
        }
    }

    @Override
    public List<Student> listStudents() {
        Session session = null;
        Transaction transaction = null;
        try {
            session = HibernateUtil.getSessionFactory().openSession();
            transaction = session.beginTransaction();
            Query query = session.createQuery("FROM Student");
            List<Student> students = query.list();
            transaction.commit();
            return students;
        } catch (Exception e) {
            e.printStackTrace();
            if (transaction != null) {
                transaction.rollback();
            }
            return null;
        } finally {
            if (session != null) {
                session.close();
            }
        }
    }

}

StudentAction.java

package codesstore.strutshibernate.action;

import java.util.Date;
import java.util.List;

import codesstore.strutshibernate.dao.StudentDao;
import codesstore.strutshibernate.dao.StudentDaoImpl;
import codesstore.strutshibernate.domain.Student;

import com.opensymphony.xwork2.ActionSupport;

public class StudentAction extends ActionSupport{
    
    private Student student;
    private List<Student> students;
    private StudentDao studentDaoImpl=new StudentDaoImpl();
    public String addStudent() {
        getStudent().setAddedTime(new Date());
        boolean isSaved=studentDaoImpl.saveStudent(getStudent());
        if(isSaved){
            addActionMessage("Successfully added student");
            return SUCCESS;
        }else {
            addActionError("Adding failed");
            return INPUT;
        }
    }
    public String listStudents(){
        students = studentDaoImpl.listStudents();
        if (students != null) {
            return SUCCESS;
        } else {
            addActionError("Student listing failed");
            return INPUT;
        }
    }
    public Student getStudent() {
        return student;
    }
    public void setStudent(Student student) {
        this.student = student;
    }
    public List<Student> getStudents() {
        return students;
    }
    public void setStudents(List<Student> students) {
        this.students = students;
    }
    
}

student.jsp

<%@ page language="java" contentType="text/html; charset=ISO-8859-1"
    pageEncoding="ISO-8859-1"%>
<%@taglib prefix="s" uri="/struts-tags" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1">
<title>Stuts 2 Hibernate - codesstore.blogspot.com</title>
</head>
<body>
<s:actionerror/>
<s:actionmessage />
<s:form action="addStudent">
    <s:textfield name="student.username" label="Username"/>
    <s:textfield name="student.email" label="Email"/>
    <s:submit value="Add"/>
</s:form>

<table>
    <s:iterator value="students">
        <tr>
            <td><s:property value="username"/></td>
            <td><s:property value="email"/></td>
            <td><s:property value="addedTime"/></td>
        </tr>
    </s:iterator>
</table>
</body>
</html>

index.jsp

<% response.sendRedirect("listStudents.action"); %>

Project structure in Eclipse.

ojdbc14.jar used to connect to Oracle database

Android Simple Calculator

2012-01-20T20:37:00.000+05:30

Simple Calculator example..
I created a simple calculator Android application to understand basic functions in Android.

CalculatorActivity.java

package codesstore.calculator;

import android.app.Activity;
import android.os.Bundle;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.EditText;
import android.widget.TextView;

public class CalculatorActivity extends Activity implements OnClickListener {
    Button buttonPlus;
    Button buttonMinus;
    Button buttonDivide;
    Button buttonMultiply;
    Button buttonOk;
    TextView textAnswer;
    TextView textOperator;
    EditText num1;
    EditText num2;
    double sum;

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);

        buttonMinus = (Button) findViewById(R.id.buttonMinus);
        buttonPlus = (Button) findViewById(R.id.buttonPlus);
        buttonDivide = (Button) findViewById(R.id.buttonDivide);
        buttonMultiply = (Button) findViewById(R.id.buttonMultiply);
        buttonOk = (Button) findViewById(R.id.buttonOk);
        num1 = (EditText) findViewById(R.id.num1);
        num2 = (EditText) findViewById(R.id.num2);
        textAnswer = (TextView) findViewById(R.id.textAnswer);
        textOperator = (TextView) findViewById(R.id.textOperator);
        
        buttonOk.setOnClickListener(this);
        buttonPlus.setOnClickListener(this);
        buttonMinus.setOnClickListener(this);
        buttonMultiply.setOnClickListener(this);
        buttonDivide.setOnClickListener(this);

    }

    @Override
    public void onClick(View src) {

        switch (src.getId()) {
        case R.id.buttonOk:
            textAnswer.setText(String.valueOf(sum));
            break;
        case R.id.buttonPlus:
            sum = Double.parseDouble(String.valueOf(num1.getText()))
                    + Double.parseDouble(String.valueOf(num2.getText()));
            textOperator.setText("+");
            break;
        case R.id.buttonMinus:
            sum = Double.parseDouble(String.valueOf(num1.getText()))
                    - Double.parseDouble(String.valueOf(num2.getText()));
            textOperator.setText("-");
            break;
        case R.id.buttonMultiply:
            sum = Double.parseDouble(String.valueOf(num1.getText()))
                    * Double.parseDouble(String.valueOf(num2.getText()));
            textOperator.setText("*");
            break;
        case R.id.buttonDivide:
            sum = Double.parseDouble(String.valueOf(num1.getText()))
                    / Double.parseDouble(String.valueOf(num2.getText()));
            textOperator.setText("/");
            break;
        }

    }
}

main.xml
Main xml is used to create user interface.

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    android:orientation="vertical" >

    <TextView
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:text="@string/title" android:gravity="center" android:textSize="30dp" android:paddingTop="3dp" android:paddingBottom="10dp"/>


    <LinearLayout
        android:id="@+id/inputs"
        android:layout_width="match_parent"
        android:layout_height="wrap_content" >


        <EditText
            android:id="@+id/num1"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_weight="1" />



        <TextView
            android:id="@+id/textOperator"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_weight="1" android:gravity="center" android:textSize="25dp"/>



        <EditText
            android:id="@+id/num2"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_weight="1" >

            <requestFocus />
        </EditText>

    </LinearLayout>


    <LinearLayout
        android:id="@+id/answerbox"
        android:layout_width="match_parent"
        android:layout_height="wrap_content" >



        <TextView
            android:id="@+id/textAnswer"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content" android:layout_weight="1" android:textSize="25dp"/>

    </LinearLayout>


    <LinearLayout
        android:id="@+id/buttons"
        android:layout_width="match_parent"
        android:layout_height="wrap_content" >

        <Button
            android:id="@+id/buttonPlus"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="+" android:layout_weight="1"/>


        <Button
            android:id="@+id/buttonMinus"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="-" android:layout_weight="1"/>


        <Button
            android:id="@+id/buttonDivide"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="/" android:layout_weight="1"/>


        <Button
            android:id="@+id/buttonMultiply"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="*" android:layout_weight="1"/>


        <Button
            android:id="@+id/buttonOk"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="=" android:layout_weight="1"/>

    </LinearLayout>

</LinearLayout>v

strings.xml

<?xml version="1.0" encoding="utf-8"?>
<resources>

    <string name="title">Simple Calculator</string>
    <string name="app_name">Calculator</string>

</resources>

R.java
This is a file auto generated by android.

/* AUTO-GENERATED FILE.  DO NOT MODIFY.
 *
 * This class was automatically generated by the
 * aapt tool from the resource data it found.  It
 * should not be modified by hand.
 */

package codesstore.calculator;

public final class R {
    public static final class attr {
    }
    public static final class drawable {
        public static final int calculator_icon=0x7f020000;
        public static final int ic_launcher=0x7f020001;
    }
    public static final class id {
        public static final int answerbox=0x7f050004;
        public static final int buttonDivide=0x7f050009;
        public static final int buttonMinus=0x7f050008;
        public static final int buttonMultiply=0x7f05000a;
        public static final int buttonOk=0x7f05000b;
        public static final int buttonPlus=0x7f050007;
        public static final int buttons=0x7f050006;
        public static final int inputs=0x7f050000;
        public static final int num1=0x7f050001;
        public static final int num2=0x7f050003;
        public static final int textAnswer=0x7f050005;
        public static final int textOperator=0x7f050002;
    }
    public static final class layout {
        public static final int main=0x7f030000;
    }
    public static final class string {
        public static final int app_name=0x7f040001;
        public static final int title=0x7f040000;
    }
}

Project structure in eclipse

outline window

Hibernate CRUD

2012-01-20T13:29:00.001+05:30

Hibernate CRUD example

hibernate.cfg.xml

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE hibernate-configuration PUBLIC "-//Hibernate/Hibernate Configuration DTD 3.0//EN" "http://hibernate.sourceforge.net/hibernate-configuration-3.0.dtd">
<hibernate-configuration>
  <session-factory>
    <property name="hibernate.dialect">org.hibernate.dialect.MySQLDialect</property>
    <property name="hibernate.connection.driver_class">com.mysql.jdbc.Driver</property>
    <property name="hibernate.connection.url">jdbc:mysql://localhost:3306/hibernatedemo</property>
    <property name="hibernate.connection.username">root</property>
    <property name="hibernate.connection.password">123</property>
    <mapping class="entity.Student" />
  </session-factory>
</hibernate-configuration>

Student.java

package entity;

import java.io.Serializable;
import javax.persistence.*;


@Entity

public class Student implements Serializable {

    @Id
    @Column(name="id")
    private Integer id;
    @Column(name="name",length=100)
    private String username;
    @Column(name="email",length=100)
    private String email;

    public String getEmail() {
        return email;
    }

    public void setEmail(String email) {
        this.email = email;
    }

    public Integer getId() {
        return id;
    }

    public void setId(Integer id) {
        this.id = id;
    }

    public String getUsername() {
        return username;
    }

    public void setUsername(String username) {
        this.username = username;
    }


}

HibernateUtil.java

package util;

import org.hibernate.SessionFactory;
import org.hibernate.cfg.AnnotationConfiguration;


public class HibernateUtil {

    private static final SessionFactory sessionFactory;

    static {
        try {
            sessionFactory = new AnnotationConfiguration().configure().buildSessionFactory();
        } catch (Exception ex) {
            
            throw new ExceptionInInitializerError();
        }
    }

    public static SessionFactory getSessionFactory() {
        return sessionFactory;
    }
}

AddStudentServlet.java

package servlet;

import java.io.IOException;
import java.io.PrintWriter;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import org.hibernate.*;
import util.HibernateUtil;
import entity.*;


public class AddStudentServlet extends HttpServlet {

    @Override
    protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {

        Session session = HibernateUtil.getSessionFactory().openSession();
        Transaction transaction = session.beginTransaction();

        Student student = new Student();
        student.setId(3);
        student.setUsername("sameera5");
        student.setEmail("jaya@yahoo.com5");

        session.save(student);
        transaction.commit();
        session.close();
    }

    @Override
    protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
    }
}

UpdateStudentServlet.java

package servlet;

import java.io.IOException;
import java.io.PrintWriter;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import org.hibernate.*;
import util.HibernateUtil;
import entity.Student;


public class UpdateStudentServlet extends HttpServlet {

    @Override
    protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        Session session = HibernateUtil.getSessionFactory().openSession();
        Transaction transaction = session.beginTransaction();

        Student s = (Student) session.get(Student.class, new Integer(1));
        System.out.println(s.getUsername());
        if (s != null) {

            s.setEmail("sampatjhh");
            s.setUsername("sampath");
            session.update(s);
        }


        transaction.commit();
        session.close();


    }
}

ViewStudentServlet.java

package servlet;

import java.io.IOException;
import java.io.PrintWriter;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import org.hibernate.*;
import util.HibernateUtil;
import entity.Student;
import java.util.List;


public class ViewStudentServlet extends HttpServlet {

  
    protected void processRequest(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {
        PrintWriter out = response.getWriter();

        Session session = HibernateUtil.getSessionFactory().openSession();
        Transaction transaction = session.beginTransaction();

        Query query = session.createQuery("FROM Student");

        List<Student> students = query.list();

        for (Student student : students) {

            out.print(student.getUsername());

        }


        transaction.commit();
        session.close();
    }

    // <editor-fold defaultstate="collapsed" desc="HttpServlet methods. Click on the + sign on the left to edit the code.">
    /** 
     * Handles the HTTP <code>GET</code> method.
     * @param request servlet request
     * @param response servlet response
     * @throws ServletException if a servlet-specific error occurs
     * @throws IOException if an I/O error occurs
     */
    @Override
    protected void doGet(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {
        processRequest(request, response);
    }

    /** 
     * Handles the HTTP <code>POST</code> method.
     * @param request servlet request
     * @param response servlet response
     * @throws ServletException if a servlet-specific error occurs
     * @throws IOException if an I/O error occurs
     */
    @Override
    protected void doPost(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {
        processRequest(request, response);
    }

    /** 
     * Returns a short description of the servlet.
     * @return a String containing servlet description
     */
    @Override
    public String getServletInfo() {
        return "Short description";
    }// </editor-fold>
}

DeleteServlet.java

package servlet;

import java.io.IOException;
import java.io.PrintWriter;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import org.hibernate.*;
import util.HibernateUtil;
import entity.Student;


public class DeleteServlet extends HttpServlet {
   

    @Override
    protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {

        Session session = HibernateUtil.getSessionFactory().openSession();
        Transaction transaction = session.beginTransaction();

        Student s=(Student) session.get(Student.class, new Integer(1));
        System.out.println(s.getUsername());
        session.delete(s);
        transaction.commit();
        session.close();
    }

    @Override
    protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
    }

}

AJAX

2011-12-08T00:06:00.000+05:30

AJAX with JSP Servlets

index.jsp

<%@ page language="java" contentType="text/html; charset=ISO-8859-1"
    pageEncoding="ISO-8859-1"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1">
<title>AJAX - codesstore.blogspot.com</title>

<script type="text/javascript">
    var XMLHttpRequestObject = false;
    
    if (window.XMLHttpRequest) {
        XMLHttpRequestObject = new XMLHttpRequest();
    } else if (window.ActiveXObject) {
        XMLHttpRequestObject = new ActiveXObject("Microsoft.XMLHTTP");
    }
    
    function getData(requestlink,parameter,value,responsedivid){
        if(XMLHttpRequestObject) {
            var obj = document.getElementById(responsedivid);
            var link=requestlink+"?"+parameter+"="+value;
    
            XMLHttpRequestObject.open("GET", link);
            XMLHttpRequestObject.onreadystatechange = function()
            {
                if (XMLHttpRequestObject.readyState == 4 && XMLHttpRequestObject.status == 200) {
                    obj.innerHTML = XMLHttpRequestObject.responseText;
    
                }
            }
    
            XMLHttpRequestObject.send(null);
        }
    }

    function postData(requestlink,parameter,value,responseid){

        if(XMLHttpRequestObject) {
            var obj = document.getElementById(responseid);
            var link=requestlink;
            XMLHttpRequestObject.open("POST", link);
            XMLHttpRequestObject.setRequestHeader('Content-Type','application/x-www-form-urlencoded; charset=UTF-8');

            var parameters=parameter+"="+value;

            XMLHttpRequestObject.onreadystatechange = function()
            {
                if (XMLHttpRequestObject.readyState == 4 && XMLHttpRequestObject.status == 200) {
                    obj.innerHTML = XMLHttpRequestObject.responseText;

                }
            }

            XMLHttpRequestObject.send(parameters);
        }
    }

</script>




</head>
<body>

<input type="button" value="get type A Data" onclick="getData('AjaxServlet','type','A','response')">
<input type="button" value="get type B Data" onclick="getData('AjaxServlet','type','B','response')">
<div id="response"></div>

<input type="button" value="get type A Data using POST" onclick="postData('AjaxServlet','type','A','post-response')">
<input type="button" value="get type B Data using POST" onclick="postData('AjaxServlet','type','B','post-response')">
<div id="post-response"></div>

</body>
</html>

AjaxServlet.java

package codesstore.ajaxtest;

import java.io.IOException;
import java.io.PrintWriter;

import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

public class AjaxServlet extends HttpServlet {
    private static final long serialVersionUID = 1L;

    public AjaxServlet() {
        super();
    }

    protected void doGet(HttpServletRequest request,
            HttpServletResponse response) throws ServletException, IOException {
        PrintWriter out = response.getWriter();
        String type = request.getParameter("type");
        if (type.equals("A")) {
            String data = "You selected Type A";
            out.print(data);
        } else if (type.equals("B")) {
            String data = "You selected Type B";
            out.print(data);
        }
    }

    protected void doPost(HttpServletRequest request,
            HttpServletResponse response) throws ServletException, IOException {
        PrintWriter out = response.getWriter();
        String type = request.getParameter("type");
        if (type.equals("A")) {
            String data = "You selected Type A. POST method used";
            out.print(data);
        } else if (type.equals("B")) {
            String data = "You selected Type B. POST method used";
            out.print(data);
        }
    }
}

JSON with Jquery JSP Servlets

2011-12-06T14:52:00.000+05:30

A simple JSON example with jquery JSP Servlets...

index.jsp

<%@ page language="java" contentType="text/html; charset=ISO-8859-1"
    pageEncoding="ISO-8859-1"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1">
<title>Insert title here</title>
<script type="text/javascript" src="http://ajax.googleapis.com/ajax/libs/jquery/1.7.1/jquery.min.js"></script>
<script type="text/javascript">
    $(document).ready(function(){ 
            $('#getData').click(function(){
                $.ajax({
                    url:'JsonServlet',
                    type:'post',
                    dataType: 'json',
                    success: function(data) {
                        $('#name').val(data.name);
                        $('#email').val(data.email);
                    }
                });
            });
    });
</script>
</head>
<body>

    Name:<input type="text" id="name"/><br/>
    Email:<input type="text" id="email"/>
    
    <input type="button" id="getData" value="Get Data"/> 

</body>
</html>

JsonServlet.java

package codesstore.json;

import java.io.IOException;
import java.io.PrintWriter;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import org.json.JSONObject;

public class JsonServlet extends HttpServlet {
    private static final long serialVersionUID = 1L;

    public JsonServlet() {
        super();
        // TODO Auto-generated constructor stub
    }

    protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {

    }

    protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
    
        PrintWriter out= response.getWriter();
        JSONObject json = new JSONObject();
        json.put("name", "Sameera Jayasekara");
        json.put("email", "codesstore@blogspot.com");
        out.print(json);
    
    }
    

}

Used json-rpc-1.0.jar file

JavaScript Check All Check boxes

2011-11-15T21:49:00.000+05:30

Check All Check boxes using JavaScript..

Select all

Box1
Box2
Box3

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>Check All...codesstore.blogspot.com</title>
<script type="text/javascript">

//----check all check boxes------
    var selectFlag=true;
    function selectAll(){
        var list=document.getElementsByName('boxlist');
        var i=0;
        if (selectFlag){
               for(i;i<list.length;i++){
                list[i].checked = true;
            }
            document.getElementById('link').innerHTML="Deselect all";
            selectFlag=false;
        }
        else{
               for(i;i<list.length;i++){
                list[i].checked = false;
            }
            document.getElementById('link').innerHTML="Select all";
            selectFlag=true;
        }
        
    }

</script>
</head>
<body>
    <a id="link" href="javascript:selectAll();">Select all</a><br>
    
    <input  type="checkbox"  name="boxlist">Box1<br>
    <input  type="checkbox"  name="boxlist">Box2<br>
    <input  type="checkbox"  name="boxlist">Box3<br>
    
</body>
</html>

Jquery Vs JavaScript - Get elements by class name

2011-11-15T21:05:00.000+05:30

getElementsByClassName JavaScript and Jquery example

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>Jquery Vs Javascript...codesstore.blogspot.com</title>
<script type="text/javascript" src="http://code.jquery.com/jquery-1.7.min.js"></script>
<script type="text/javascript">

//-------------Jquery hide divs---------------------
    $(document).ready(function(){
        $("#jquery-hide").click(function(){
            $(".hideme").hide();
        });
    });
    
//-------------JavaScript hide divs------------------

function hideAll(){
    
    var divs=document.getElementsByClassName("hideme");
    for(var i=0;i<divs.length;i++){
        divs[i].style.display="none";
        
    }
    
}

//fixes for IE
onload=function(){
    if (document.getElementsByClassName == undefined) {
        document.getElementsByClassName = function(className)
        {
            var hasClassName = new RegExp("(?:^|\\s)" + className + "(?:$|\\s)");
            var allElements = document.getElementsByTagName("*");
            var results = [];
            var element;
            for (var i = 0; (element = allElements[i]) != null; i++) {
                var elementClass = element.className;
                if (elementClass && elementClass.indexOf(className) != -1 && hasClassName.test(elementClass))
                    results.push(element);
            }
            return results;
        }
    }
}
    
    
</script>
</head>
<body>

    <div class="hideme">
        Content 1
    </div>
    
    <div class="hideme">
        Content 2
    </div>
    
    <a href="#" id="jquery-hide">Jquery Hide</a>
    <a href="javascript:hideAll()" id="js-hide">Javascript Hide</a>
    
</body>
</html>

When using javascript getElementsByClassName not working on IE.I found fixes for IE from a forum...

SCBCD 5 Short Notes

2011-10-25T21:44:00.000+05:30

My SCBCD 5 Short Notes..

1)

@PostConstruct
public void initialize( ){ }

@PreDestroy
public void cleanup( ){ }

@PrePassivate
public void cleanup( ){ }

@PostActivate
public void openConnection( ){ }

Access modifier can be public
                                     protected
                                     default
                                     private
Not static
Not Final
Not throw checked Exceptions

@Remove
public void cancel( ){ }

@PostConstruct, @PreDestroy can be used with stateful, stateless session beans
@PrePassivate, @PostActivate, @Remove used with stateful session beans

2)
Transaction attributes
Reference : EJB 3 in Action

Transaction Attribute	Caller Transaction Exists?	Effect
REQUIRED	No	Container creates a new transaction.
REQUIRED	Yes	Method joins the caller’s transaction.
REQUIRES_NEW	No	Container creates a new transaction.
REQUIRES_NEW	Yes	Container creates a new transaction and the caller’s transaction is suspended
SUPPORTS	No	No transaction is used.
SUPPORTS	Yes	Method joins the caller’s transaction.
MANDATORY	No	javax.ejb.EJBTransactionRequired-Exception is thrown.
MANDATORY	Yes	Method joins the caller’s transaction.
NOT_SUPPORTED	No	No transaction is used.
NOT_SUPPORTED	Yes	The caller’s transaction is suspended and the method is called without a transaction
NEVER	No	No transaction is used.
NEVER	Yes	javax.ejb.EJBException is thrown

@Entity
public class Project{
    @ManyToMany(mappedBy="projects")
    Set<Employee> emps;
}

@Entity
public class Employee{
    @ManyToMany(targetEntity=Project.class)
    Collection projects;
}

If we not use Generics we have to use targetEntity

4 )

@MessageDriven
public class MyMessageBean implements MessageListener{
    
    public MyMessageBean(){}
    
    public void onMesage(Message message){
        
    }
}

5) EJB Roles

Enterprise Bean Provider
Application Assembler
Deployer
EJB Server Provider
EJB Container Provider
Persistence Provider
System Administrator

6)
@PersistenceUnit
EntityManagerFactory emf;

@PersistenceContext
EntityManager em;

7)Defining a Runtime Exception

@ApplicationException
public class MyException extends java.lang.RuntimeException

8) ejb-jar is a contract between ,

Bean Provider and Application Assembler
Application Assembler and Deployer