org.codehaus.groovy.transform.trait

Class Traits

java.lang.Object

org.codehaus.groovy.transform.trait.Traits

public abstract class Traits
extends Object

A collection of utility methods used to deal with traits.

Since:

2.3.0

Author:

Cédric Champeau

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static interface	Traits.Implemented Internal annotation used to indicate which methods in a trait interface have a default implementation.
static interface	Traits.TraitBridge Internal annotation used to indicate that a method is a bridge method to a trait default implementation.

Field Summary

Fields

Modifier and Type	Field and Description
static ClassNode	GENERATED_PROXY_CLASSNODE
static ClassNode	IMPLEMENTED_CLASSNODE
static ClassNode	SELFTYPE_CLASSNODE
static String	THIS_OBJECT
static Class	TRAIT_CLASS
static ClassNode	TRAIT_CLASSNODE
static ClassNode	TRAITBRIDGE_CLASSNODE

Constructor Summary

Constructors

Constructor and Description
Traits()

Method Summary

Methods

Modifier and Type	Method and Description
static LinkedHashSet<ClassNode>	collectAllInterfacesReverseOrder(ClassNode cNode, LinkedHashSet<ClassNode> interfaces) Collects all interfaces of a class node, but reverses the order of the declaration of direct interfaces of this class node.
static LinkedHashSet<ClassNode>	collectSelfTypes(ClassNode receiver, LinkedHashSet<ClassNode> selfTypes) Collects all the self types that a type should extend or implement, given the traits is implements.
static LinkedHashSet<ClassNode>	collectSelfTypes(ClassNode receiver, LinkedHashSet<ClassNode> selfTypes, boolean checkInterfaces, boolean checkSuper) Collects all the self types that a type should extend or implement, given the traits is implements.
static String[]	decomposeSuperCallName(String origName) Returns the name of a method without the super trait specific prefix.
static <T> T	getAsType(Object self, Class<T> clazz) Converts a class implementing some trait into a target class.
static Method	getBridgeMethodTarget(Method someMethod) Reflection API to find the method corresponding to the default implementation of a trait, given a bridge method.
static boolean	hasDefaultImplementation(Method method) Indicates whether a method in a trait interface has a default implementation.
static boolean	hasDefaultImplementation(MethodNode method) Indicates whether a method in a trait interface has a default implementation.
static boolean	isAnnotatedWithTrait(ClassNode cNode) Returns true if the specified class node is annotated with the Trait interface.
static boolean	isBridgeMethod(Method someMethod) Reflection API to indicate whether some method is a bridge method to the default implementation of a trait.
static boolean	isTrait(Class clazz) Returns true if the specified class is a trait.
static boolean	isTrait(ClassNode cNode) Returns true if the specified class node is a trait.

Methods inherited from class java.lang.Object

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

Field Detail

IMPLEMENTED_CLASSNODE

public static final ClassNode IMPLEMENTED_CLASSNODE

TRAITBRIDGE_CLASSNODE

public static final ClassNode TRAITBRIDGE_CLASSNODE

TRAIT_CLASS

public static final Class TRAIT_CLASS

TRAIT_CLASSNODE

public static final ClassNode TRAIT_CLASSNODE

GENERATED_PROXY_CLASSNODE

public static final ClassNode GENERATED_PROXY_CLASSNODE

SELFTYPE_CLASSNODE

public static final ClassNode SELFTYPE_CLASSNODE

THIS_OBJECT

public static final String THIS_OBJECT

See Also:

Constant Field Values

Constructor Detail

Traits

public Traits()

Method Detail

isTrait

public static boolean isTrait(ClassNode cNode)

Returns true if the specified class node is a trait.

Parameters:

cNode - a class node to test

Returns:

true if the classnode represents a trait

isTrait

public static boolean isTrait(Class clazz)

Returns true if the specified class is a trait.

Parameters:

clazz - a class to test

Returns:

true if the classnode represents a trait

isAnnotatedWithTrait

public static boolean isAnnotatedWithTrait(ClassNode cNode)

Returns true if the specified class node is annotated with the Trait interface.

Parameters:

cNode - a class node

Returns:

true if the specified class node is annotated with the Trait interface.

hasDefaultImplementation

public static boolean hasDefaultImplementation(MethodNode method)

Indicates whether a method in a trait interface has a default implementation.

Parameters:

method - a method node

Returns:

true if the method has a default implementation in the trait

hasDefaultImplementation

public static boolean hasDefaultImplementation(Method method)

Indicates whether a method in a trait interface has a default implementation.

Parameters:

method - a method node

Returns:

true if the method has a default implementation in the trait

isBridgeMethod

public static boolean isBridgeMethod(Method someMethod)

Reflection API to indicate whether some method is a bridge method to the default implementation of a trait.

Parameters:

someMethod - a method node

Returns:

null if it is not a method implemented in a trait. If it is, returns the method from the trait class.

getBridgeMethodTarget

public static Method getBridgeMethodTarget(Method someMethod)

Reflection API to find the method corresponding to the default implementation of a trait, given a bridge method.

Parameters:

someMethod - a method node

Returns:

null if it is not a method implemented in a trait. If it is, returns the method from the trait class.

getAsType

public static <T> T getAsType(Object self,
              Class<T> clazz)

Converts a class implementing some trait into a target class. If the trait is a dynamic proxy and that the target class is assignable to the target object of the proxy, then the target object is returned. Otherwise, falls back to DefaultGroovyMethods.asType(java.lang.Object, Class)

Parameters:

self - an object to be coerced to some class

clazz - the class to be coerced to

Returns:

the object coerced to the target class, or the proxy instance if it is compatible with the target class.

decomposeSuperCallName

public static String[] decomposeSuperCallName(String origName)

Returns the name of a method without the super trait specific prefix. If the method name doesn't correspond to a super trait method call, the result will be null.

Parameters:

origName - the name of a method

Returns:

null if the name doesn't start with the super trait prefix, otherwise the name without the prefix

collectAllInterfacesReverseOrder

public static LinkedHashSet<ClassNode> collectAllInterfacesReverseOrder(ClassNode cNode,
                                                        LinkedHashSet<ClassNode> interfaces)

Collects all interfaces of a class node, but reverses the order of the declaration of direct interfaces of this class node. This is used to make sure a trait implementing A,B where both A and B have the same method will take the method from B (latest), aligning the behavior with categories.

Parameters:

cNode - a class node

interfaces - ordered set of interfaces

collectSelfTypes

public static LinkedHashSet<ClassNode> collectSelfTypes(ClassNode receiver,
                                        LinkedHashSet<ClassNode> selfTypes)

Collects all the self types that a type should extend or implement, given the traits is implements. Collects from interfaces and superclasses too.

Parameters:

receiver - a class node that may implement a trait

selfTypes - a collection where the list of self types will be written

Returns:

the selfTypes collection itself

Since:

2.4.0

collectSelfTypes

public static LinkedHashSet<ClassNode> collectSelfTypes(ClassNode receiver,
                                        LinkedHashSet<ClassNode> selfTypes,
                                        boolean checkInterfaces,
                                        boolean checkSuper)

Collects all the self types that a type should extend or implement, given the traits is implements.

Parameters:

receiver - a class node that may implement a trait

selfTypes - a collection where the list of self types will be written

checkInterfaces - should the interfaces that the node implements be collected too

checkSuper - should we collect from the superclass too

Returns:

the selfTypes collection itself

Since:

2.4.0