Package org.junit.runners

Class BlockJUnit4ClassRunner

  • All Implemented Interfaces:
    Describable, Filterable, Orderable, Sortable
    Direct Known Subclasses:
    BlockJUnit4ClassRunnerWithParameters, JUnit4, Theories
    public class BlockJUnit4ClassRunner
extends ParentRunner<FrameworkMethod>
    Implements the JUnit 4 standard test case class model, as defined by the annotations in the org.junit package. Many users will never notice this class: it is now the default test class runner, but it should have exactly the same behavior as the old test class runner (JUnit4ClassRunner).

    BlockJUnit4ClassRunner has advantages for writers of custom JUnit runners that are slight changes to the default behavior, however:

    • It has a much simpler implementation based on Statements, allowing new operations to be inserted into the appropriate point in the execution flow.
    • It is published, and extension and reuse are encouraged, whereas JUnit4ClassRunner was in an internal package, and is now deprecated.

    In turn, in 2009 we introduced Rules. In many cases where extending BlockJUnit4ClassRunner was necessary to add new behavior, Rules can be used, which makes the extension more reusable and composable.

    Since:
    4.5

    • Method Detail

      • computeTestMethods

        protected java.util.List<FrameworkMethod> computeTestMethods()
        Returns the methods that run tests. Default implementation returns all methods annotated with @Test on this class and superclasses that are not overridden.

      • validateConstructor

        protected void validateConstructor​(java.util.List<java.lang.Throwable> errors)
        Adds to errors if the test class has more than one constructor, or if the constructor takes parameters. Override if a subclass requires different validation rules.

      • validateOnlyOneConstructor

        protected void validateOnlyOneConstructor​(java.util.List<java.lang.Throwable> errors)
        Adds to errors if the test class has more than one constructor (do not override)

      • validateZeroArgConstructor

        protected void validateZeroArgConstructor​(java.util.List<java.lang.Throwable> errors)
        Adds to errors if the test class's single constructor takes parameters (do not override)

      • validateInstanceMethods

        @Deprecated
protected void validateInstanceMethods​(java.util.List<java.lang.Throwable> errors)
        Deprecated.
        Adds to errors for each method annotated with @Test, @Before, or @After that is not a public, void instance method with no arguments.

      • validateFields

        protected void validateFields​(java.util.List<java.lang.Throwable> errors)

      • validateTestMethods

        protected void validateTestMethods​(java.util.List<java.lang.Throwable> errors)
        Adds to errors for each method annotated with @Testthat is not a public, void instance method with no arguments.

      • createTest

        protected java.lang.Object createTest()
                               throws java.lang.Exception
        Returns a new fixture for running a test. Default implementation executes the test class's no-argument constructor (validation should have ensured one exists).
        Throws:
        java.lang.Exception

      • createTest

        protected java.lang.Object createTest​(FrameworkMethod method)
                               throws java.lang.Exception
        Returns a new fixture to run a particular test method against. Default implementation executes the no-argument createTest() method.
        Throws:
        java.lang.Exception
        Since:
        4.13

      • testName

        protected java.lang.String testName​(FrameworkMethod method)
        Returns the name that describes method for Descriptions. Default implementation is the method's name

      • methodBlock

        protected Statement methodBlock​(FrameworkMethod method)
        Returns a Statement that, when executed, either returns normally if method passes, or throws an exception if method fails. Here is an outline of the default implementation:
        • Invoke method on the result of createTest(org.junit.runners.model.FrameworkMethod), and throw any exceptions thrown by either operation.
        • HOWEVER, if method's @Test annotation has the Test.expected() attribute, return normally only if the previous step threw an exception of the correct type, and throw an exception otherwise.
        • HOWEVER, if method's @Test annotation has the timeout attribute, throw an exception if the previous step takes more than the specified number of milliseconds.
        • ALWAYS run all non-overridden @Before methods on this class and superclasses before any of the previous steps; if any throws an Exception, stop execution and pass the exception on.
        • ALWAYS run all non-overridden @After methods on this class and superclasses after any of the previous steps; all After methods are always executed: exceptions thrown by previous steps are combined, if necessary, with exceptions from After methods into a MultipleFailureException.
        • ALWAYS allow @Rule fields to modify the execution of the above steps. A Rule may prevent all execution of the above steps, or add additional behavior before and after, or modify thrown exceptions. For more information, see TestRule
        This can be overridden in subclasses, either by overriding this method, or the implementations creating each sub-statement.

      • withPotentialTimeout

        @Deprecated
protected Statement withPotentialTimeout​(FrameworkMethod method,
                                         java.lang.Object test,
                                         Statement next)
        Deprecated.
        Returns a Statement: if method's @Test annotation has the timeout attribute, throw an exception if next takes more than the specified number of milliseconds.

      • withBefores

        protected Statement withBefores​(FrameworkMethod method,
                                java.lang.Object target,
                                Statement statement)
        Returns a Statement: run all non-overridden @Before methods on this class and superclasses before running next; if any throws an Exception, stop execution and pass the exception on.

      • withAfters

        protected Statement withAfters​(FrameworkMethod method,
                               java.lang.Object target,
                               Statement statement)
        Returns a Statement: run all non-overridden @After methods on this class and superclasses before running next; all After methods are always executed: exceptions thrown by previous steps are combined, if necessary, with exceptions from After methods into a MultipleFailureException.

      • rules

        protected java.util.List<MethodRule> rules​(java.lang.Object target)
        Parameters:
        target - the test case instance
        Returns:
        a list of MethodRules that should be applied when executing this test

      • getTestRules

        protected java.util.List<TestRule> getTestRules​(java.lang.Object target)
        Parameters:
        target - the test case instance
        Returns:
        a list of TestRules that should be applied when executing this test