How Do You Test an Unexpected Exception with JUnit?

JUnit Questions and Answers

(Continued from previous question...)

How Do You Test an Unexpected Exception with JUnit?

If you want to test a method that could raise an unexpected exception, you should design a test that:

• Put the test code inside a "try" block".
• Catch any unexpected exception object.
• Fail the test witl Assert.fail().

JUnit runner will fail this test if the test code raised any unexpected exception.

Here is a good test class that test any unexpected exception raised by the get() method of the ArrayList class:

import org.junit.*;
import java.util.*;

// by FYICenter.com
public class UnexpectedExceptionTest1 { 
  @Test public void testGet() {
    ArrayList emptyList = new ArrayList