JUnit – Timeout Test

If a test is taking longer than a defined “timeout” to finish, a TestTimedOutException will be thrown and the test marked failed. See the following example :

P.S Tested with JUnit 4.12

1. Timeout Example

This timeout example only applies to a single test method. And the timeout value is in milliseconds.

package com.mkyong;

import org.junit.Test;

public class TimeoutTest {

    //This test will always failed :)
    @Test(timeout = 1000)
    public void infinity() {
        while (true) ;
    }

    //This test can't run more than 5 seconds, else failed
    @Test(timeout = 5000)
    public void testSlowMethod() {
        //...
    }

}

This timeout test is useful to test on the method performance.

2. Global Timeout Rule Example

This example shows you how to create a global timeout rule, this rule will apply to all the test methods in a class.

package com.mkyong;

import org.junit.Rule;
import org.junit.Test;
import org.junit.rules.Timeout;

import java.util.concurrent.TimeUnit;

public class TimeoutRuleTest {

    //global timeout rule
    @Rule
    public Timeout globalTimeout = Timeout.seconds(1);

	//This test will be failed, because it will take more than 1 second to finish!
    @Test
    public void testSlowMethod1() throws InterruptedException {
        //...
        TimeUnit.SECONDS.sleep(5000);
    }

	//passed
    @Test
    public void testSlowMethod2() {
        //...
    }

}

In the above example, a global Timeout rule is declared, both the testSlowMethod1() and testSlowMethod2() must finish the test within 1 second, else the test will be failed.

P.S The rule also applies on @Before and @After methods.

References

1. @Test JavaDoc
2. Timeout Rule JavaDoc