Package org.apache.tapestry5.commons.internal.services

## Class GenericsResolverImpl

- java.lang.Object
- - org.apache.tapestry5.commons.internal.services.GenericsResolverImpl

- All Implemented Interfaces:
    `GenericsResolver`

      public class GenericsResolverImpl
      extends Object
      implements GenericsResolver

  Implementation copied from Tapestry 5.4's GenericUtils (commons package).

- - ### Nested Class Summary

    - ### Nested classes/interfaces inherited from interface org.apache.tapestry5.commons.services.GenericsResolver

      `GenericsResolver.Provider`

  - ### Constructor Summary

    Constructors
    Constructor | Description
    --- | ---
    `GenericsResolverImpl()` |

  - ### Method Summary

    All Methods Static Methods Instance Methods Concrete Methods
    Modifier and Type | Method | Description
    --- | --- | ---
    `Class` | `asClass​(Type actualType)` | Get the class represented by the reflected type.
    `Type` | `extractActualType​(Type containingType, Field field)` | Analyzes the method in the context of containingClass and returns the Class that is represented by the method's generic return type.
    `Type` | `extractActualType​(Type containingType, Method method)` | Analyzes the method in the context of containingClass and returns the Class that is represented by the method's generic return type.
    `Class` | `extractGenericFieldType​(Class containingClass, Field field)` | Analyzes the field in the context of containingClass and returns the Class that is represented by the field's generic type.
    `Class<?>` | `extractGenericReturnType​(Class<?> containingClass, Method method)` | Analyzes the method in the context of containingClass and returns the Class that is represented by the method's generic return type.
    `Type` | `resolve​(Type type, Type containingType)` | Resolves the type parameter based on the context of the containingType.
    `static String` | `toString​(Type type)` | Convert the type into a string.

    - ### Methods inherited from class java.lang.Object

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

- - ### Constructor Detail

    - #### GenericsResolverImpl

          public GenericsResolverImpl()

  - ### Method Detail

    - #### extractGenericReturnType

          public Class<?> extractGenericReturnType​(Class<?> containingClass,
                                                   Method method)

      Analyzes the method in the context of containingClass and returns the Class that is represented by the method's generic return type. Any parameter information in the generic return type is lost. If you want to preserve the type parameters of the return type consider using `extractActualType(java.lang.reflect.Type, java.lang.reflect.Method)`.
      Specified by:
        `extractGenericReturnType` in interface `GenericsResolver`
      Parameters:
        `containingClass` - class which either contains or inherited the method
        `method` - method from which to extract the return type
      Returns:
        the class represented by the methods generic return type, resolved based on the context .
      See Also:
        `extractActualType(java.lang.reflect.Type, java.lang.reflect.Method)`, `resolve(java.lang.reflect.Type,java.lang.reflect.Type)`, `asClass(java.lang.reflect.Type)`

    - #### extractGenericFieldType

          public Class extractGenericFieldType​(Class containingClass,
                                               Field field)

      Analyzes the field in the context of containingClass and returns the Class that is represented by the field's generic type. Any parameter information in the generic type is lost, if you want to preserve the type parameters of the return type consider using `getTypeVariableIndex(java.lang.reflect.TypeVariable)`.
      Specified by:
        `extractGenericFieldType` in interface `GenericsResolver`
      Parameters:
        `containingClass` - class which either contains or inherited the field
        `field` - field from which to extract the type
      Returns:
        the class represented by the field's generic type, resolved based on the containingClass.
      See Also:
        `extractActualType(java.lang.reflect.Type, java.lang.reflect.Field)`, `resolve(java.lang.reflect.Type,java.lang.reflect.Type)`, `asClass(java.lang.reflect.Type)`

    - #### extractActualType

          public Type extractActualType​(Type containingType,
                                        Method method)

      Analyzes the method in the context of containingClass and returns the Class that is represented by the method's generic return type. Any parameter information in the generic return type is lost.
      Specified by:
        `extractActualType` in interface `GenericsResolver`
      Parameters:
        `containingType` - Type which is/represents the class that either contains or inherited the method
        `method` - method from which to extract the generic return type
      Returns:
        the generic type represented by the methods generic return type, resolved based on the containingType.
      See Also:
        `resolve(java.lang.reflect.Type,java.lang.reflect.Type)`

    - #### extractActualType

          public Type extractActualType​(Type containingType,
                                        Field field)

      Analyzes the method in the context of containingClass and returns the Class that is represented by the method's generic return type. Any parameter information in the generic return type is lost.
      Specified by:
        `extractActualType` in interface `GenericsResolver`
      Parameters:
        `containingType` - Type which is/represents the class that either contains or inherited the field
        `field` - field from which to extract the generic return type
      Returns:
        the generic type represented by the methods generic return type, resolved based on the containingType.
      See Also:
        `resolve(java.lang.reflect.Type,java.lang.reflect.Type)`

    - #### resolve

          public Type resolve​(Type type,
                              Type containingType)

      Resolves the type parameter based on the context of the containingType. `TypeVariable` will be unwrapped to the type argument resolved form the class hierarchy. This may be something other than a simple Class if the type argument is a ParameterizedType for instance (e.g. `List<E>; List<Map<Long, String>>`, E would be returned as a ParameterizedType with the raw type Map and type arguments Long and String.
      Specified by:
        `resolve` in interface `GenericsResolver`
      Parameters:
        `type` - the generic type (ParameterizedType, GenericArrayType, WildcardType, TypeVariable) to be resolved
        `containingType` - the type which his
      Returns:
        the type resolved to the best of our ability.
      Since:
        5.2.?

    - #### asClass

          public Class asClass​(Type actualType)

      Get the class represented by the reflected type. This method is lossy; You cannot recover the type information from the class that is returned. `TypeVariable` the first bound is returned. If your type variable extends multiple interfaces that information is lost. `WildcardType` the first lower bound is returned. If the wildcard is defined with upper bounds then `Object` is returned.
      Specified by:
        `asClass` in interface `GenericsResolver`
      Parameters:
        `actualType` - a Class, ParameterizedType, GenericArrayType
      Returns:
        the un-parameterized class associated with the type.

    - #### toString

          public static String toString​(Type type)

      Convert the type into a string. The string representation approximates the code that would be used to define the type.
      Parameters:
        `type` - - the type.
      Returns:
        a string representation of the type, similar to how it was declared.