LoadTest is a test decorator that runs a test with a simulated number of concurrent users and iterations. In its simplest form, a LoadTest is constructed with a test to decorate and the number of concurrent users.
For example, to create a load test of 10 concurrent users with each user running ExampleTest once and all users started simultaneously, use:
or, to load test a single test method, use:Test loadTest = new LoadTest(new TestSuite(ExampleTest.class), 10);
Test loadTest = new LoadTest(new ExampleTest("testSomething"), 10); The load can be ramped by specifying a pluggable Timer instance which prescribes the delay between the addition of each concurrent user. A ConstantTimer has a constant delay, with a zero value indicating that all users will be started simultaneously. A RandomTimer has a random delay with a uniformly distributed variation.
For example, to create a load test of 10 concurrent users with each user running ExampleTest.testSomething() once and with a one second delay between the addition of users, use:
Timer timer = new ConstantTimer(1000); Test loadTest = new LoadTest(new ExampleTest("testSomething"), 10, timer); In order to simulate each concurrent user running a test for a specified number of iterations, a LoadTest can be constructed to decorate a RepeatedTest. Alternatively, a LoadTest convenience constructor specifying the number of iterations is provided which creates a RepeatedTest.
For example, to create a load test of 10 concurrent users with each user running ExampleTest.testSomething() for 20 iterations, and with a one second delay between the addition of users, use:
Timer timer = new ConstantTimer(1000); Test repeatedTest = new RepeatedTest(new ExampleTest("testSomething"), 20); Test loadTest = new LoadTest(repeatedTest, 10, timer); or, alternatively, use: Timer timer = new ConstantTimer(1000); Test loadTest = new LoadTest(new ExampleTest("testSomething"), 10, 20, timer); A LoadTest can be decorated as a TimedTest to test the elapsed time of the load test. For example, to decorate the load test constructed above as a timed test with a maximum elapsed time of 2 seconds, use: Test timedTest = new TimedTest(loadTest, 2000);
By default, a LoadTest does not enforce test atomicity (as defined in transaction processing) if its decorated test spawns threads, either directly or indirectly. In other words, if a decorated test spawns a thread and then returns control without waiting for its spawned thread to complete, then the test is assumed to be transactionally complete.
If threads are integral to the successful completion of a decorated test, meaning that the decorated test should not be treated as complete until all of its threads complete, then setEnforceTestAtomicity(true) should be invoked to enforce test atomicity. This effectively causes the load test to wait for the completion of all threads belonging to the same ThreadGroup as the thread running the decorated test.
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