ParentRunner (JUnit 4.12 API)

java.lang.Object
- org.junit.runner.Runner
- - org.junit.runners.ParentRunner<T>

All Implemented Interfaces:

Describable, Filterable, Sortable

Direct Known Subclasses:

BlockJUnit4ClassRunner, Suite
```
public abstract class ParentRunner<T>
extends Runner
implements Filterable, Sortable
```
Provides most of the functionality specific to a Runner that implements a "parent node" in the test tree, with children defined by objects of some data type T. (For BlockJUnit4ClassRunner, T is Method . For Suite, T is Class.) Subclasses must implement finding the children of the node, describing each child, and running each child. ParentRunner will filter and sort children, handle @BeforeClass and @AfterClass methods, handle annotated ClassRules, create a composite Description, and run children sequentially.

Since:

4.5

Constructor Summary

Constructors
Modifier Constructor and Description

protected ParentRunner(Class<?> testClass)
Constructs a new ParentRunner that will run @TestClass

Constructors
Modifier	Constructor and Description
`protected`	`ParentRunner(Class<?> testClass)` Constructs a new `ParentRunner` that will run `@TestClass`

Method Summary

All Methods Instance Methods Abstract Methods Concrete Methods
Modifier and Type	Method and Description
`protected Statement`	`childrenInvoker(RunNotifier notifier)` Returns a `Statement`: Call `runChild(Object, RunNotifier)` on each object returned by `getChildren()` (subject to any imposed filter and sort)
`protected Statement`	`classBlock(RunNotifier notifier)` Constructs a `Statement` to run all of the tests in the test class.
`protected List<TestRule>`	`classRules()`
`protected void`	`collectInitializationErrors(List<Throwable> errors)` Adds to `errors` a throwable for each problem noted with the test class (available from `getTestClass()`).
`protected TestClass`	`createTestClass(Class<?> testClass)`
`protected abstract Description`	`describeChild(T child)` Returns a `Description` for `child`, which can be assumed to be an element of the list returned by `getChildren()`
`void`	`filter(Filter filter)` Remove tests that don't pass the parameter `filter`.
`protected abstract List<T>`	`getChildren()` Returns a list of objects that define the children of this Runner.
`Description`	`getDescription()`
`protected String`	`getName()` Returns a name used to describe this Runner
`protected Annotation[]`	`getRunnerAnnotations()`
`TestClass`	`getTestClass()` Returns a `TestClass` object wrapping the class to be executed.
`protected boolean`	`isIgnored(T child)` Evaluates whether a child is ignored.
`void`	`run(RunNotifier notifier)` Run the tests for this runner.
`protected abstract void`	`runChild(T child, RunNotifier notifier)` Runs the test corresponding to `child`, which can be assumed to be an element of the list returned by `getChildren()`.
`protected void`	`runLeaf(Statement statement, Description description, RunNotifier notifier)` Runs a `Statement` that represents a leaf (aka atomic) test.
`void`	`setScheduler(RunnerScheduler scheduler)` Sets a scheduler that determines the order and parallelization of children.
`void`	`sort(Sorter sorter)` Sorts the tests using `sorter`
`protected void`	`validatePublicVoidNoArgMethods(Class<? extends Annotation> annotation, boolean isStatic, List<Throwable> errors)` Adds to `errors` if any method in this class is annotated with `annotation`, but: is not public, or takes parameters, or returns something other than void, or is static (given `isStatic is false`), or is not static (given `isStatic is true`).
`protected Statement`	`withAfterClasses(Statement statement)` Returns a `Statement`: run all non-overridden `@AfterClass` methods on this class and superclasses before executing `statement`; all AfterClass methods are always executed: exceptions thrown by previous steps are combined, if necessary, with exceptions from AfterClass methods into a `MultipleFailureException`.
`protected Statement`	`withBeforeClasses(Statement statement)` Returns a `Statement`: run all non-overridden `@BeforeClass` methods on this class and superclasses before executing `statement`; if any throws an Exception, stop execution and pass the exception on.

Methods inherited from class org.junit.runner.Runner
testCount

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Constructor Detail
  - ParentRunner
```
protected ParentRunner(Class<?> testClass)
                throws InitializationError
```
    Constructs a new ParentRunner that will run @TestClass
    
    Throws:
    
    InitializationError
- Method Detail
  - createTestClass
```
protected TestClass createTestClass(Class<?> testClass)
```
  - getChildren
```
protected abstract List<T> getChildren()
```
    Returns a list of objects that define the children of this Runner.
  - describeChild
```
protected abstract Description describeChild(T child)
```
    Returns a Description for child, which can be assumed to be an element of the list returned by getChildren()
  - runChild
```
protected abstract void runChild(T child,
                                 RunNotifier notifier)
```
    Runs the test corresponding to child, which can be assumed to be an element of the list returned by getChildren(). Subclasses are responsible for making sure that relevant test events are reported through notifier
  - collectInitializationErrors
```
protected void collectInitializationErrors(List<Throwable> errors)
```
    Adds to errors a throwable for each problem noted with the test class (available from getTestClass()). Default implementation adds an error for each method annotated with @BeforeClass or @AfterClass that is not public static void with no arguments.
  - validatePublicVoidNoArgMethods
```
protected void validatePublicVoidNoArgMethods(Class<? extends Annotation> annotation,
                                              boolean isStatic,
                                              List<Throwable> errors)
```
    Adds to errors if any method in this class is annotated with annotation, but:
    - is not public, or
    - takes parameters, or
    - returns something other than void, or
    - is static (given isStatic is false), or
    - is not static (given isStatic is true).
  - classBlock
```
protected Statement classBlock(RunNotifier notifier)
```
    Constructs a Statement to run all of the tests in the test class. Override to add pre-/post-processing. Here is an outline of the implementation:
    1. Determine the children to be run using getChildren() (subject to any imposed filter and sort).
    2. If there are any children remaining after filtering and ignoring, construct a statement that will:
      
      Apply all ClassRules on the test-class and superclasses.
      
      Run all non-overridden @BeforeClass methods on the test-class and superclasses; if any throws an Exception, stop execution and pass the exception on.
      
      Run all remaining tests on the test-class.
      
      Run all non-overridden @AfterClass methods on the test-class and superclasses: exceptions thrown by previous steps are combined, if necessary, with exceptions from AfterClass methods into a MultipleFailureException.
    Returns:
    
    Statement
  - withBeforeClasses
```
protected Statement withBeforeClasses(Statement statement)
```
    Returns a Statement: run all non-overridden @BeforeClass methods on this class and superclasses before executing statement; if any throws an Exception, stop execution and pass the exception on.
  - withAfterClasses
```
protected Statement withAfterClasses(Statement statement)
```
    Returns a Statement: run all non-overridden @AfterClass methods on this class and superclasses before executing statement; all AfterClass methods are always executed: exceptions thrown by previous steps are combined, if necessary, with exceptions from AfterClass methods into a MultipleFailureException.
  - classRules
```
protected List<TestRule> classRules()
```
    Returns:
    
    the ClassRules that can transform the block that runs each method in the tested class.
  - childrenInvoker
```
protected Statement childrenInvoker(RunNotifier notifier)
```
    Returns a Statement: Call runChild(Object, RunNotifier) on each object returned by getChildren() (subject to any imposed filter and sort)
  - isIgnored
```
protected boolean isIgnored(T child)
```
    Evaluates whether a child is ignored. The default implementation always returns false.
    BlockJUnit4ClassRunner, for example, overrides this method to filter tests based on the Ignore annotation.
  - getName
```
protected String getName()
```
    Returns a name used to describe this Runner
  - getTestClass
```
public final TestClass getTestClass()
```
    Returns a TestClass object wrapping the class to be executed.
  - runLeaf
```
protected final void runLeaf(Statement statement,
                             Description description,
                             RunNotifier notifier)
```
    Runs a Statement that represents a leaf (aka atomic) test.
  - getRunnerAnnotations
```
protected Annotation[] getRunnerAnnotations()
```
    Returns:
    
    the annotations that should be attached to this runner's description.
  - getDescription
```
public Description getDescription()
```
    Specified by:
    
    getDescription in interface Describable
    
    Specified by:
    
    getDescription in class Runner
    
    Returns:
    
    a Description showing the tests to be run by the receiver
  - run
```
public void run(RunNotifier notifier)
```
    Description copied from class: Runner
    
    Run the tests for this runner.
    
    Specified by:
    
    run in class Runner
    
    Parameters:
    
    notifier - will be notified of events while tests are being run--tests being started, finishing, and failing
  - filter
```
public void filter(Filter filter)
            throws NoTestsRemainException
```
    Description copied from interface: Filterable
    
    Remove tests that don't pass the parameter filter.
    
    Specified by:
    
    filter in interface Filterable
    
    Parameters:
    
    filter - the Filter to apply
    
    Throws:
    
    NoTestsRemainException - if all tests are filtered out
  - sort
```
public void sort(Sorter sorter)
```
    Description copied from interface: Sortable
    
    Sorts the tests using sorter
    
    Specified by:
    
    sort in interface Sortable
    
    Parameters:
    
    sorter - the Sorter to use for sorting the tests
  - setScheduler
```
public void setScheduler(RunnerScheduler scheduler)
```
    Sets a scheduler that determines the order and parallelization of children. Highly experimental feature that may change.

Class ParentRunner<T>

Constructor Summary

Method Summary

Methods inherited from class org.junit.runner.Runner

Methods inherited from class java.lang.Object

Constructor Detail

ParentRunner

Method Detail

createTestClass

getChildren

describeChild

runChild

collectInitializationErrors

validatePublicVoidNoArgMethods

classBlock

withBeforeClasses

withAfterClasses

classRules

childrenInvoker

isIgnored

getName

getTestClass

runLeaf

getRunnerAnnotations

getDescription

run

filter

sort

setScheduler