Program: Simple JUnit test using @Test annotation.

JUnit is a simple framework to write repeatable tests. It is an instance of the xUnit architecture for unit testing frameworks. We are using Junit 4 for examples shown here. Here is a simple example. MyEvenOdd class provides a method isEvenNumber() to test whether the given number is even or odd number. We have written MyEvenOddTest class to test the functionality of MyEvenOdd class.

@org.junit.Test annotation: The Test annotation tells JUnit that the public void method to which it is attached can be run as a test case. To run the method, JUnit first constructs a fresh instance of the class then invokes the annotated method. Any exceptions thrown by the test will be reported by JUnit as a failure. If no exceptions are thrown, the test is assumed to have succeeded.

assertEquals(String message, Object expected, Object actual): Asserts that two objects are equal. If they are not, an AssertionError is thrown with the given message. If expected and actual are null, they are considered equal.

In Eclipse, run MyEvenOddTest class as JUnit Test.

package com.java2novice.junit.samples;

public class MyEvenOdd {

	public boolean isEvenNumber(int number){
		
		boolean result = false;
		if(number%2 == 0){
			result = true;
		}
		return result;
	}
}

package com.java2novice.junit.tests;

import static org.junit.Assert.assertEquals;

import org.junit.Test;

import com.java2novice.junit.samples.MyEvenOdd;

public class MyEvenOddTest {

	@Test
	public void testEvenOddNumber(){
		MyEvenOdd meo = new MyEvenOdd();
		assertEquals("10 is a even number", true, meo.isEvenNumber(10));
	}
}

Java JUnit Examples

1. Simple JUnit test using @Test annotation.
2. List of JUnit annotations.
3. Assertion method Assert.assertArrayEquals() example.
4. How to do JUnit test for comapring two list of user defined objects?
5. Assertion method Assert.assertEquals() example.
6. Assertion method Assert.assertFalse() example.
7. Assertion method Assert.assertTrue() example.
8. Assertion method Assert.assertNotNull() example.
9. Assertion method Assert.assertNull() example.
10. Assertion method Assert.assertNotSame() example.
11. Assertion method Assert.assertSame() example.