Package org.junit.jupiter.engine.execution

Class DefaultParameterContext

java.lang.Object

org.junit.jupiter.engine.execution.DefaultParameterContext

All Implemented Interfaces:

ParameterContext

class DefaultParameterContext
extends Object
implements ParameterContext

Since:

5.0

Field Summary

Fields

Modifier and Type	Field	Description
private final int	index
private final Parameter	parameter
private final Optional<Object>	target

Constructor Summary

Constructors

Constructor	Description
DefaultParameterContext(Parameter parameter, int index, Optional<Object> target)

Method Summary

Modifier and Type	Method	Description
<A extends Annotation> Optional<A>	findAnnotation(Class<A> annotationType)	Find the first annotation of annotationType that is either present or meta-present on the Parameter for this context.
<A extends Annotation> List<A>	findRepeatableAnnotations(Class<A> annotationType)	Find all repeatable annotations of annotationType that are either present or meta-present on the Parameter for this context.
private AnnotatedElement	getEffectiveAnnotatedParameter()	Due to a bug in javac on JDK versions prior to JDK 9, looking up annotations directly on a Parameter will fail for inner class constructors.
int	getIndex()	Get the index of the Parameter for this context within the parameter list of the Executable that declares the parameter.
Parameter	getParameter()	Get the Parameter for this context.
Optional<Object>	getTarget()	Get the target on which the Executable that declares the Parameter for this context will be invoked, if available.
boolean	isAnnotated(Class<? extends Annotation> annotationType)	Determine if an annotation of annotationType is either present or meta-present on the Parameter for this context.
String	toString()

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Methods inherited from interface org.junit.jupiter.api.extension.ParameterContext

getDeclaringExecutable

Field Details

parameter

private final Parameter parameter

index

private final int index

target

private final Optional<Object> target

Constructor Details

DefaultParameterContext

DefaultParameterContext(Parameter parameter,
 int index,
 Optional<Object> target)

Method Details

getParameter

public Parameter getParameter()

Description copied from interface: ParameterContext

Get the Parameter for this context.

WARNING

When searching for annotations on the parameter in this context, favor ParameterContext.isAnnotated(Class), ParameterContext.findAnnotation(Class), and ParameterContext.findRepeatableAnnotations(Class) over methods in the Parameter API due to a bug in javac on JDK versions prior to JDK 9.

Specified by:

getParameter in interface ParameterContext

Returns:

the parameter; never null

See Also:

• ParameterContext.getIndex()

getIndex

public int getIndex()

Description copied from interface: ParameterContext

Get the index of the Parameter for this context within the parameter list of the Executable that declares the parameter.

Specified by:

getIndex in interface ParameterContext

Returns:

the index of the parameter

See Also:

• ParameterContext.getParameter()
• Executable.getParameters()

getTarget

public Optional<Object> getTarget()

Description copied from interface: ParameterContext

Get the target on which the Executable that declares the Parameter for this context will be invoked, if available.

Specified by:

getTarget in interface ParameterContext

Returns:

an Optional containing the target on which the Executable will be invoked; never null but will be empty if the Executable is a constructor or a static method.

isAnnotated

public boolean isAnnotated(Class<? extends Annotation> annotationType)

Description copied from interface: ParameterContext

Determine if an annotation of annotationType is either present or meta-present on the Parameter for this context.

WARNING

Favor the use of this method over directly invoking AnnotatedElement.isAnnotationPresent(Class) due to a bug in javac on JDK versions prior to JDK 9.

Specified by:

isAnnotated in interface ParameterContext

Parameters:

annotationType - the annotation type to search for; never null

Returns:

true if the annotation is present or meta-present

See Also:

• ParameterContext.findAnnotation(Class)
• ParameterContext.findRepeatableAnnotations(Class)

findAnnotation

public <A extends Annotation> Optional<A> findAnnotation(Class<A> annotationType)

Description copied from interface: ParameterContext

Find the first annotation of annotationType that is either present or meta-present on the Parameter for this context.

WARNING

Favor the use of this method over directly invoking annotation lookup methods in the Parameter API due to a bug in javac on JDK versions prior to JDK 9.

Specified by:

findAnnotation in interface ParameterContext

Type Parameters:

A - the annotation type

Parameters:

annotationType - the annotation type to search for; never null

Returns:

an Optional containing the annotation; never null but potentially empty

See Also:

• ParameterContext.isAnnotated(Class)
• ParameterContext.findRepeatableAnnotations(Class)

findRepeatableAnnotations

public <A extends Annotation> List<A> findRepeatableAnnotations(Class<A> annotationType)

Description copied from interface: ParameterContext

Find all repeatable annotations of annotationType that are either present or meta-present on the Parameter for this context.

WARNING

Favor the use of this method over directly invoking annotation lookup methods in the Parameter API due to a bug in javac on JDK versions prior to JDK 9.

Specified by:

findRepeatableAnnotations in interface ParameterContext

Type Parameters:

A - the annotation type

Parameters:

annotationType - the repeatable annotation type to search for; never null

Returns:

the list of all such annotations found; neither null nor mutable, but potentially empty

See Also:

• ParameterContext.isAnnotated(Class)
• ParameterContext.findAnnotation(Class)
• Repeatable

getEffectiveAnnotatedParameter

private AnnotatedElement getEffectiveAnnotatedParameter()

Due to a bug in javac on JDK versions prior to JDK 9, looking up annotations directly on a Parameter will fail for inner class constructors.

Bug in javac on JDK versions prior to JDK 9

The parameter annotations array in the compiled byte code for the user's test class excludes an entry for the implicit enclosing instance parameter for an inner class constructor.

Workaround

JUnit provides a workaround for this off-by-one error by helping extension authors to access annotations on the preceding Parameter object (i.e., index - 1). The current index must never be zero in such situations since JUnit Jupiter should never ask a ParameterResolver to resolve a parameter for the implicit enclosing instance parameter.

WARNING

The AnnotatedElement returned by this method should never be cast and treated as a Parameter since the metadata (e.g., Parameter.getName(), Parameter.getType(), etc.) will not match those for the declared parameter at the given index in an inner class constructor.

Returns:

the actual Parameter for this context, or the effective Parameter if the aforementioned bug is detected

toString

public String toString()

Overrides:

toString in class Object