Execute JUnit Tests with JUnitCore

Often it is desired that one should be able to run only certain testcases whenever a new feature is introduced. This can be achieved using JUnitCore class.
JUnitCore is an inbuilt class in Junit package. It is based on Facade design pattern. This class is used to run only specified test classes.

Lets suppose we have two new features in our application named FeatureOne and FeatureTwo. Sample testcases for both features can be as follows:

package com.howtodoinjava.junit;

import junit.framework.Assert;

import org.junit.Test;

public class TestFeatureOne {
	@Test
	public void testFirstFeature()
	{
		Assert.assertTrue(true);
	}
}

and

package com.howtodoinjava.junit;

import junit.framework.Assert;

import org.junit.Test;

public class TestFeatureTwo {
	@Test
	public void testSecondFeature()
	{
		Assert.assertTrue(true);
	}
}

To run above features only, we can write a suite like this.

package com.howtodoinjava.junit.suite;

import java.util.ArrayList;
import java.util.List;

import org.junit.runner.JUnitCore;
import org.junit.runner.Result;
import org.junit.runner.notification.Failure;

import com.howtodoinjava.junit.TestFeatureOne;
import com.howtodoinjava.junit.TestFeatureTwo;

@SuppressWarnings("rawtypes")
public class WithJUnitCore
{
	public static void main(String[] args)
	{
		List testCases = new ArrayList();

		//Add test cases
		testCases.add(TestFeatureOne.class);
		testCases.add(TestFeatureTwo.class);

		for (Class testCase : testCases)
               {
                    runTestCase(testCase);
               }
	}

    private static void runTestCase(Class testCase)
    {
        Result result = JUnitCore.runClasses(testCase);
        for (Failure failure : result.getFailures())
        {
            System.out.println(failure.toString());
        }
    }
}

Happy Learning !!