Class TestFramework
MultithreadedTestCase
.
The method runOnce(MultithreadedTestCase)
can be used
to run a MultithreadedTestCase once. The method
runManyTimes(MultithreadedTestCase, int)
can be used to
run a MultithreadedTestCase multiple times (to see if different interleavings
produce different behaviors).
Each test case starts by running the initialize method, followed by all the thread methods in different threads, and finally the finish method when all threads have finished. The thread methods are run in a new thread group, and are regulated by a separate clock thread. The clock thread checks periodically to see if all threads are blocked. If all threads are blocked and at least one is waiting for a tick, the clock thread advances the clock to the next desired tick. (A slight delay -- about a clock period -- is applied before advancing the clock to ensure that this is not done prematurely and any threads trying to unblock are given a chance to do so.)
The clock thread also detects deadlock (when all threads are blocked, none are waiting for a tick, and none are in state TIMED_WAITING), and can stop a test that is going on too long (a thread is in state RUNNABLE for too long.)
Since the test case threads are placed in a new thread group, any other threads created by these test cases will be placed in this thread group by default. All threads in the thread group will be considered by the clock thread when deciding whether to advance the clock, declare a deadlock, or stop a long-running test.
The framework catches exceptions thrown in the threads and propagates them to the JUnit test (It also throws AssertionErrors)
This class also defines a number of parameters to be used to control the tests. Set command line parameter -Dtunit.runLimit=n to cause a test case to fail if at least one thread stays in a runnable state for more than n seconds without becoming blocked or waiting for a metronome tick. Set command line parameter -Dtunit.clockPeriod=p to cause the clock thread to check the status of all the threads every p milliseconds.
- Since:
- 1.0
- See Also:
-
Field Summary
FieldsModifier and TypeFieldDescriptionstatic final String
Command line key for indicating the regularity (in milliseconds) with which the clock thread regulates the thread methods.static final Integer
The default clock period in millisecondsstatic final Integer
The default run limit in secondsstatic final String
Command line key for indicating the time limit (in seconds) for runnable threads. -
Constructor Summary
Constructors -
Method Summary
Modifier and TypeMethodDescriptionstatic void
addSetUpAndTearDown
(MultithreadedTest mtc, junit.framework.TestCase tc) Update a given test to call "setUp" and "tearDown" before and after running the test respectively.static junit.framework.TestSuite
buildTestSuite
(Class<?> c) Scan through a given classc
to find any inner classes that implementTest
.static junit.framework.TestSuite
buildTestSuite
(Class<?> c, String suiteName) Scan through a given classc
to find any inner classes that implementTest
.static void
runInstrumentedManyTimes
(MultithreadedTestCase test, int count, int[] failureCount) Run multithreaded test case multiple times using the default or global settings for clock period and run limit.static void
runManyTimes
(MultithreadedTestCase test, int count) Run multithreaded test case multiple times using the default or global settings for clock period and run limit.static void
runManyTimes
(MultithreadedTestCase test, int count, Integer clockPeriod, Integer runLimit) Run multithreaded test case multiple times.static void
runOnce
(MultithreadedTestCase test) Run a multithreaded test case once, using the default or global settings for clock period and run limitstatic void
runOnce
(MultithreadedTestCase test, Integer clockPeriod, Integer runLimit) Run multithreaded test case once.static void
Change/set the system property for the clock periodstatic void
Change/set the system property for the run limit
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Field Details
-
CLOCKPERIOD_KEY
Command line key for indicating the regularity (in milliseconds) with which the clock thread regulates the thread methods.- See Also:
-
RUNLIMIT_KEY
Command line key for indicating the time limit (in seconds) for runnable threads.- See Also:
-
DEFAULT_CLOCKPERIOD
The default clock period in milliseconds -
DEFAULT_RUNLIMIT
The default run limit in seconds
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Constructor Details
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TestFramework
public TestFramework()
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-
Method Details
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setGlobalClockPeriod
Change/set the system property for the clock period- Parameters:
v
- the new value for the clock period
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setGlobalRunLimit
Change/set the system property for the run limit- Parameters:
v
- the new value for the run limit
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runInstrumentedManyTimes
public static void runInstrumentedManyTimes(MultithreadedTestCase test, int count, int[] failureCount) throws Throwable Run multithreaded test case multiple times using the default or global settings for clock period and run limit. This method adds instrumentation to count the number of times failures occur (an exception is thrown). If the arrayfailureCount
is initialized to be of at least size 1, it returns this count infailureCount[0]
. If failures do occur, it saves the first failure, and then throws it after running the testcount
times.- Parameters:
test
- The multithreaded test case to runcount
- the number of times to run the test casefailureCount
- if this array is initialzed to at least size 1, the number of failures is returned infailureCount[0]
- Throws:
Throwable
- if there is at least one failure -- the first failure is thrown
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runManyTimes
Run multithreaded test case multiple times using the default or global settings for clock period and run limit. The value of this is limited, since even running a test case a thousand or a million times may not expose any bugs dependent upon particular thread interleavings.- Parameters:
test
- The multithreaded test case to runcount
- the number of times to run the test case- Throws:
Throwable
- -- if any of the test runs fails, the exception is thrown immediately without completing the rest of the test runs.
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runManyTimes
public static void runManyTimes(MultithreadedTestCase test, int count, Integer clockPeriod, Integer runLimit) throws Throwable Run multithreaded test case multiple times. The value of this is limited, since even running a test case a thousand or a million times may not expose any bugs dependent upon particular thread interleavings.- Parameters:
test
- The multithreaded test case to runcount
- the number of times to run the test caseclockPeriod
- The period (in ms) between checks for the clock (or null for default or global setting)runLimit
- The limit to run the test in seconds (or null for default or global setting)- Throws:
Throwable
- -- if any of the test runs fails, the exception is thrown immediately without completing the rest of the test runs.
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runOnce
Run a multithreaded test case once, using the default or global settings for clock period and run limit- Parameters:
test
- The multithreaded test case to run- Throws:
Throwable
- if the test runs fails or causes an exception
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runOnce
public static void runOnce(MultithreadedTestCase test, Integer clockPeriod, Integer runLimit) throws Throwable Run multithreaded test case once.- Parameters:
test
- The multithreaded test case to runclockPeriod
- The period (in ms) between checks for the clock (or null for default or global setting)runLimit
- The limit to run the test in seconds (or null for default or global setting)- Throws:
Throwable
- if the test runs fails or causes an exception
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buildTestSuite
Scan through a given classc
to find any inner classes that implementTest
. If the classes have a no-arg constructor, they are instantiated added them to a TestSuite. If the inner classes are not declared static then an instance of the class represented byc
(created with a no-arg constructor) is used to construct the inner class. If no relevant inner classes are found, then an empty TestSuite is returned.- Parameters:
c
- the class to scan for relevant inner classes- Returns:
- A TestSuite containing one test for each relevant inner class
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buildTestSuite
Scan through a given classc
to find any inner classes that implementTest
. If the classes have a no-arg constructor, they are instantiated added them to a TestSuite. If the inner classes are not declared static then an instance of the class represented byc
(created with a no-arg constructor) is used to construct the inner class. If no relevant inner classes are found, then an empty TestSuite is returned.If the class is a TestCase, then an instance of it is passed to any non-static innerclass and the appropriate setUp and tearDown methods are called.
- Parameters:
c
- the class to scan for relevant inner classessuiteName
- A name for the TestSuite- Returns:
- A TestSuite containing one test for each relevant inner class
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addSetUpAndTearDown
public static void addSetUpAndTearDown(MultithreadedTest mtc, junit.framework.TestCase tc) throws SecurityException, NoSuchMethodException Update a given test to call "setUp" and "tearDown" before and after running the test respectively. Update is done by creating a new test. This assumes that the provided TestCase instance was used to create the Test, otherwise it does little good to call the "setUp" and "tearDown" method in the TestCase. Throws any exceptions that occur along the process. In this case, just use the old uninstrumented test.- Parameters:
mtc
- the test to updatetc
- the TestCase that contains the setUp and tearDown methods called- Throws:
SecurityException
NoSuchMethodException
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