org.junit.Test Maven / Gradle / Ivy
package org.junit;
import java.lang.annotation.ElementType;
import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;
import java.lang.annotation.Target;
/**
* 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.
*
* A simple test looks like this:
*
* public class Example {
* @Test
* public void method() {
* org.junit.Assert.assertTrue( new ArrayList().isEmpty() );
* }
* }
*
*
* The Test annotation supports two optional parameters.
* The first, expected, declares that a test method should throw
* an exception. If it doesn't throw an exception or if it throws a different exception
* than the one declared, the test fails. For example, the following test succeeds:
*
* @Test(expected=IndexOutOfBoundsException.class) public void outOfBounds() {
* new ArrayList<Object>().get(1);
* }
*
* If the exception's message or one of its properties should be verified, the
* {@link org.junit.rules.ExpectedException ExpectedException} rule can be used. Further
* information about exception testing can be found at the
* JUnit Wiki.
*
* The second optional parameter, timeout, causes a test to fail if it takes
* longer than a specified amount of clock time (measured in milliseconds). The following test fails:
*
* @Test(timeout=100) public void infinity() {
* while(true);
* }
*
* Warning: while timeout is useful to catch and terminate
* infinite loops, it should not be considered deterministic. The
* following test may or may not fail depending on how the operating system
* schedules threads:
*
* @Test(timeout=100) public void sleep100() {
* Thread.sleep(100);
* }
*
* THREAD SAFETY WARNING: Test methods with a timeout parameter are run in a thread other than the
* thread which runs the fixture's @Before and @After methods. This may yield different behavior for
* code that is not thread safe when compared to the same test method without a timeout parameter.
* Consider using the {@link org.junit.rules.Timeout} rule instead, which ensures a test method is run on the
* same thread as the fixture's @Before and @After methods.
*
* @since 4.0
*/
@Retention(RetentionPolicy.RUNTIME)
@Target({ElementType.METHOD})
public @interface Test {
/**
* Default empty exception
*/
static class None extends Throwable {
private static final long serialVersionUID = 1L;
private None() {
}
}
/**
* Optionally specify expected, a Throwable, to cause a test method to succeed if
* and only if an exception of the specified class is thrown by the method. If the Throwable's
* message or one of its properties should be verified, the
* {@link org.junit.rules.ExpectedException ExpectedException} rule can be used instead.
*/
Class expected() default None.class;
/**
* Optionally specify timeout in milliseconds to cause a test method to fail if it
* takes longer than that number of milliseconds.
*
* THREAD SAFETY WARNING: Test methods with a timeout parameter are run in a thread other than the
* thread which runs the fixture's @Before and @After methods. This may yield different behavior for
* code that is not thread safe when compared to the same test method without a timeout parameter.
* Consider using the {@link org.junit.rules.Timeout} rule instead, which ensures a test method is run on the
* same thread as the fixture's @Before and @After methods.
*
*/
long timeout() default 0L;
}