Downloading and Installing NetBeans IDE

These instructions describe how to download and install NetBeans, a commonly used IDE for Java programming. Using an IDE means that you have all of the tools you need in one place (your "development environment") instead of having to organize things manually. Use the instructions in Step 2 to write a simple Java program called "Hello.java" and then compile and run it.

2. Writing a Hello-world Java Program in NetBeans

Step 0: Launch NetBeans

Launch NetBeans. If the "Start Page" appears, close it by clicking the "cross" button next to the "Start Page" title.

Step 1: Create a New Project

For each Java application, you need to create a "project" to keep all the source files, classes and relevant resources.

  1. From "File" menu ⇒ Choose "New Project...".
  2. The "Choose Project" diglog pops up ⇒ Under "Categories", choose "Java" ⇒ Under "Projects", choose "Java Application" ⇒ "Next".
  3. The "Name and Location" dialog pops up ⇒ Under "Project Name", enter "FirstProject" ⇒ In "Project Location", select a suitable directory to save your works ⇒ Uncheck "Use Dedicated Folder for Storing Libraries" ⇒ Uncheck "Create Main class"  ⇒ Finish.

Step 2: Write a Hello-world Java Program

  1. Right-click on "FirstProject" ⇒ New ⇒ Java Class (OR choose the "File" menu ⇒ "New File..." ⇒ Categories: "Java", File Types: "Java Class" ⇒ "Next").
  2. The "Name and Location" dialog pops up ⇒ In "Class Name", enter "Hello" ⇒ Delete the content in "Package" if it is not empty ⇒ "Finish".
  3. The source file "Hello.java" appears in the editor panel. Enter the following codes: 
    public class Hello {
    public static void main(String[] args) {
        System.out.println("Hello, world");
    }
}

Step 3: Compile & Execute

There is no need to "compile" the source code in NetBeans explicitly, as NetBeans performs the so-called incremental compilation  (i.e., the source statement is compiled as and when it is entered).

To run the program, right-click anywhere in the source (or from the "Run" menu) ⇒ Run File. Observe the output on the output console.

Notes:

  • You should create a NEW Java project for EACH of your Java application.
  • Nonetheless, NetBeans allows you to keep more than one programs in a project, which is handy for writing toy programs (such as your tutorial exercises). To run a particular program, open and right-click on the source file ⇒ Run File.