File IO in java.

Added a PPT for File handling in java in two parts yet more to come. The content is for the educational purpose only. Material have been taken from book, internet with no intention of breaking any rights issues.

I/O In Java Part 2 from ashishspace

I/O in java Part 1 from ashishspace

Creating Stateless EJB with GlassFish

In this sample example we will be creating the stateless ejb with glasshfish and ant. Using ant is optional as it will automate the build on basis of the script.

Prerequisite:

1. GlassFish version 3.1 [i am using zip format]. Click to download
2. Apache-ant version 1.8.2 [i am using .tar.gz format ]. Click to download
3. Java up and running [ JDK ]

Note: For path classpath on windows use ; to append and on nix use :
We won't go in setting the path for anything. We will be using the bin folder to run. But yes for easy build, path can be set. The path can be set for glassfish and ant in following ways.

1. For GlassFish : GLASSFISH_HOME=<absolute path of glassfish>/bin
2. For ant : ANT_HOME=<absolutepath of ant >/bin

As we will go without path so we need to shift to bin folder to GlassFish extracted folder.

terminal screen to run glassfish

To test administrative console open the browser with url http://localhost:4848. We will get

Bingo! We are done for making the sample application.

Lets create HelloWorld Application. We need three java file Hello.java, HelloLocal.java, HelloBean.java and one xml file i.e. build.xml. We will create the package com.asb. Our directory structure will look like



This structure can exist in any drive or directory.

Code for the files
----------
Hello.java
----------

package com.asb;
public interface Hello
{
    public String sayHello();
    public String sayHelloRemote();
}

---------------
HelloLocal.java
---------------

package com.asb;
public interface HelloLocal
{
    public String sayHello();
    public String sayHelloLocal();
}

--------------
HelloBean.java
--------------

package com.asb;
import javax.ejb.Stateless;
import javax.ejb.Remote;
import javax.ejb.Local;

@Stateless
@Remote(Hello.class)
@Local(HelloLocal.class)
public class HelloBean implements Hello,HelloLocal
{
    public String sayHello()
    {
        return "Hello World";
    }
    public String sayHelloLocal()
    {
        return "Hello Local World";
    }
    public String sayHelloRemote()
    {
       return "Hello Remote World";
    }
}

---------
build.xml
---------

<project name="HelloEJB" basedir=".">
    <description>
         Simple Build File
    </description>
    <!-- set global properties for this build -->
    <property name="src.dir" location="src"/>
    <property name="build.dir" location="build"/>
    <property name="dist.dir" location="dist"/>

    <target name="init">
        <!-- For timeStamp -->
        <tstamp/>
        <mkdir dir="${build.dir}"/>
    </target>

    <target name="compile" depends="init">
        <javac srcdir="${src.dir}" destdir="${build.dir}" includeantruntime="true"/>
    </target>

    <target name="dist" depends="compile">
        <mkdir dir="${dist.dir}/lib"/>
        <jar jarfile="${dist.dir}/lib/HelloBean-${DSTAMP}.jar" basedir="${build.dir}"/>
    </target>

    <target name="clean">
        <delete dir="${build.dir}"/>
        <delete dir="${dist.dir}"/>
    </target>
</project>

To build using ant we will go to bin directory where the ant was extracted.

ant/bin>./ant compile -buildfile <path to helloapp>/HelloEJB/build.xml -lib <path to glassfish>/lib/javaee.jar

ant/bin>./ant dist -buildfile <path to helloapp>/HelloEJB/build.xml -lib <path to glassfish>/lib/javaee.jar

glassfish/bin>./asadmin start-domainglassfish/bin>./asadmin deploy <path to="" helloapp>/HelloEJB/dist/lib/HelloBean-<date>.jar
We are done with the deployment.

To run we need client program

package com.asb.client;

import javax.naming.*;
import com.asb.Hello;

public class HelloClient
{
    public static void main(String args[])
    {
        try
        {
            InitialContext ctx = new InitialContext();
            Hello h = (Hello) ctx.lookup("com.asb.Hello");
            System.out.println(h.sayHello());
            System.out.println(h.sayHelloRemote());
        }
        catch(Exception e)
        {
            e.printStackTrace();
        }
    }
}

To compile and run

javac -cp <path to glassfish>/lib/javaee.jar:. HelloClient.java
java -cp <path to glassfish>/lib/javaee.jar:<path to glassfish>/lib/appserv-rt.jar HelloClient

We are done we will get the output HelloWorld.

Java and MSAccess

A simple video on how to connect MSAcess and Java.

Creating Hello World Servlet

A simple video [ screencast ] to show how to develop the HelloWorld Servlet.

Replacing old *nix with Fedora 14

Last time when i installed fedora am not that happy; the problem may be on my side or on other side; i dont know.

I thought lets give it a try again. I installed fedora 14, installation was smooth but i faced some problem in creating the bootable usb drive. But it got resolved in few tries. I installed fedora and trust me installation was too smooth.

After the installation i need to make it ready for using [ missing softwares ]

I started with Java.

Installing Java

• Download jdk and jre from goo.gl/nqkjo. Download bin files.
• Change it to become executable [ chmod +x file ]
• Run bin file
• Using alternative --install command.

Ok Lets try it out. You may require root access.

1. Open Terminal
2. wget goo.gl/JMYjs This will download jdk-6u22-linux-i586-rpm.bin
3. chmod +x jdk-6u22-linux-i586-rpm.bin
4. ./jdk-6u22-linux-i586-rpm.bin
5. alternatives --install /usr/bin/java java /usr/java/jdk1.6.0_22/jre/bin/java 20000
6. alternatives --install /usr/bin/javaws javaws /usr/java/jdk1.6.0_22/jre/bin/javaws 20000
7. java -version

Next is openoffice
yum install openoffice*

To enjoy mp3 and other restricted softwares we need to enable the restricted repos.

This is all for Fedora 14.

After the Currency symbol its time for Indian browser

It is again time for us to take proud, after the Indian currency symbol, their is a new browser for the Indians. The browser named “Epic” : The first ever web browser for India develop by Hidden Reflex. It has so many cool features that make it more user friendly. It comes with the side bar for the various services or widgets which includes

• News from the india
• Transliterator for Indian scripts, it supports 12indian languages
• Skins
• Antivirus  powered by eset
• Editing and saving html files
• Snippets that let you drag and drop the content and save it for later use
• Video service that let you stream video in small pane and let you keep browsing the web
• Todos
• Facebook
• Twitter
• Gmail
• Orkut
• Yahoo
• Maps
• Travel
• Jobs
• Games
• Backup

Have a look at  screenshots.

Its still not available on linux only exe version is out.  As it is built on Mozilla so it supports all the add-ons and plug-in that fire fox supports. It also comes with Epic App that allow to add more to the sidebar. With few hours of usage i feel its good one. One should give it a try.

Buzz

Today when i logged in gmail account it will ask you to go for Buzz!!! A new social networking initiative (is it correct!!!) by Google people. It let me share picasa photos,flickr, google reader, status, chatlogs, links, twitter ... and many more. Using it i had a felling like twitter and bit of facebook. Yes we can tweak to what to be shared in what manner (public or private). . It also suggest the list of your contacts to follow and following category. It overcomes the limitation of 140 character twitter. :) Now posting of long text is allowed. The best part is ...... Inbox Integration. The look and feel awesome (thumbnails).

@replies are also supported.

Although your inbox will be vibrating to show the new notification for the buzz you receives. Its ok when we get so many things bundled up.