Eclipse Cookbook

5.2. Testing an Application with JUnit

Problem

You want to create a JUnit test case.

Solution

Create a JUnit-based class, and implement the tests you want to run. Then use the JUnit plug-in to see your test results immediately.

Discussion

As an example, we’re going to test the application TestApp, shown in Example 5-1, which uses a class named TestClass. This application has two methods: get, which returns a string, and set, which returns a confirming value of true if the value you pass is 0 or greater.

Example 5-1. A simple Java class

package org.cookbook.ch05;

public class TestClass
{
    public String get( ) {
         return "Test String";
    }
    
    public boolean set(int index) {
         if (index < 0) {
             return false;
         } else {
             return true;
         }
    }
}

To test this application, use the JUnit Wizard plug-in to create a new class in the project that extends the JUnit TestCase class. To invoke the wizard, right-click the class you want to test, TestClass here, and select New→ Other to open the New dialog shown in Figure 5-3.

Figure 5-3. Creating a new JUnit TestCase-based class

Expand the Java node in the left pane, and select JUnit. In the right pane, select TestCase. Click Next, displaying the dialog shown in Figure 5-4.

Figure 5-4. Configuring a JUnit test class

The JUnit convention is to name test cases by adding “Test” ...