JUnit 5 @Timeout Annotation

In JUnit 5, the Timeout Test feature is used to ensure that a test completes within a specified time limit. If the test takes longer than the defined duration, it will fail automatically. This is useful for detecting performance issues or infinite loops.

Why Use Timeout?

• To prevent tests from running indefinitely.
• To detect performance bottlenecks.
• To ensure your application responds within acceptable time limits.

JUnit 5 Syntax

@Test
@Timeout(value = 2, unit = TimeUnit.SECONDS)
void testMethod() {
    // your test code
}

Example

import org.junit.jupiter.api.Test;
import org.junit.jupiter.api.Timeout;

import java.util.concurrent.TimeUnit;

import static java.lang.Thread.sleep;

public class TimeoutExampleTest {

    @Test
    @Timeout(value = 2, unit = TimeUnit.SECONDS)
    void shouldCompleteWithinTwoSeconds() throws InterruptedException {
        // Simulate a task that takes 1 second
        sleep(1000);
    }

    @Test
    @Timeout(value = 1, unit = TimeUnit.SECONDS)
    void shouldFailDueToTimeout() throws InterruptedException {
        // Simulate a task that takes 2 seconds
        sleep(2000);
    }
}

Explanation

• shouldCompleteWithinTwoSeconds – This test will pass because it completes within the timeout limit.
• shouldFailDueToTimeout – This test will fail because it exceeds the 1-second timeout.

Remember to import the @Timeout annotation from org.junit.jupiter.api.Timeout.