How to Create Your First Java Program on Ubuntu Linux

Step-by-Step Guide

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   Step 1: Open terminal on your system after installing Java on your system.

   Open up a terminal on Ubuntu Linux and create your Java applications directory. ,, Type or copy/paste: cd Java_Applications This will change you into your newly created Java_Applications directory. , In this example we will use the traditional first program known as “Hello world”.
   
   This will open up a blank Java text file to work with and now we will insert some text into our Java file.
   
   So using nano or gedit we will issue the following command:
   Type: nano HelloWorld.java or type gedit HelloWorld.java , import javax.swing.*; public class HelloWorld extends JFrame { public static void main(String[] args) { new HelloWorld(); } public HelloWorld() { JPanel panel1 = new JPanel(); JLabel label1 = new JLabel("Hello, World, this is my first Java program on Ubuntu Linux"); panel1.add(label1); this.add(panel1); this.setTitle("Hello World"); this.setSize(500,500); this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); this.setVisible(true); } } ,, Type javac HelloWorld.java (This will fail if you don't have javac installed, if it fails, either follow the instructions in the introduction or type on your command line: sudo apt-get install openjdk-7-jdk) , Type: java HelloWorld
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   Step 2: Create a directory to hold your Java programs.

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   Step 3: Type: mkdir Java_Applications This will create your Java_Applications directory.

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   Step 4: Navigate to your Java_Applications directory.

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   Step 5: Use a text editor such as nano or gedit to create a java file.

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   Step 6: Enter the following code below.

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   Step 7: Save the file as HelloWorld.java

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   Step 8: Compile the HelloWorld.java file into a Java class file by issuing the following command below.

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   Step 9: Run or execute your Java class file by issuing the following command.

Detailed Guide

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