Measuring Test Run Time

Annotating a test with @Stopwatch will measure the time the test takes to execute and will report the result to the TestReporter. How that information is displayed depends on the tool used to run the tests and how it processes test report entries.

Usage

@Stopwatch can be applied to a method to report its execution time:

@Test
@Stopwatch
void test() {
    // execution time will be reported
}

It can also be applied to a class, in which case it reports the execution times of each test as if it were applied to each method individually:

@Stopwatch
class TestCases {

    @Test
    void test_1() {
        // execution time will be reported
    }

    @Test
    void test_s() {
        // execution time will be reported
    }

}

It can also be applied to a class and a method therein but since a class-level annotation already works as if each method was annotated, the method-level annotations would be redundant.

Output

This is how IntelliJ displays a report entry (in the Run/Debug panel):

timestamp = 2022-05-26T12:16:14.021646, StopwatchExtension = Execution of 'test()' took [11] ms.

Other tools may or may not print report entries.

The most reliable way to gather entries is to create a TestExecutionListener and register it with the launcher. Report entries from the stopwatch extension can be identified by checking their key-value pairs - at least one key will start with the string "StopwatchExtension".

Thread-Safety

This extension is safe to use during parallel test execution.