org.apache.commons.lang3.reflect

Class TypeUtils

java.lang.Object

org.apache.commons.lang3.reflect.TypeUtils

public class TypeUtils
extends java.lang.Object

Utility methods focusing on type inspection, particularly with regard to generics.

Since:

3.0

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
private static class	TypeUtils.GenericArrayTypeImpl GenericArrayType implementation class.
private static class	TypeUtils.ParameterizedTypeImpl ParameterizedType implementation class.
static class	TypeUtils.WildcardTypeBuilder WildcardType builder.
private static class	TypeUtils.WildcardTypeImpl WildcardType implementation class.

Field Summary

Fields

Modifier and Type	Field and Description
static java.lang.reflect.WildcardType	WILDCARD_ALL A wildcard instance matching ?.

Constructor Summary

Constructors

Constructor and Description
TypeUtils() TypeUtils instances should NOT be constructed in standard programming.

Method Summary

Modifier and Type	Method and Description
private static <T> java.lang.StringBuilder	appendAllTo(java.lang.StringBuilder buf, java.lang.String sep, T... types) Append types to buf with separator sep.
private static void	appendRecursiveTypes(java.lang.StringBuilder buf, int[] recursiveTypeIndexes, java.lang.reflect.Type[] argumentTypes)
private static java.lang.String	classToString(java.lang.Class<?> c) Format a Class as a String.
static boolean	containsTypeVariables(java.lang.reflect.Type type) Learn, recursively, whether any of the type parameters associated with type are bound to variables.
private static boolean	containsVariableTypeSameParametrizedTypeBound(java.lang.reflect.TypeVariable<?> typeVariable, java.lang.reflect.ParameterizedType p)
static java.util.Map<java.lang.reflect.TypeVariable<?>,java.lang.reflect.Type>	determineTypeArguments(java.lang.Class<?> cls, java.lang.reflect.ParameterizedType superType) Tries to determine the type arguments of a class/interface based on a super parameterized type's type arguments.
private static boolean	equals(java.lang.reflect.GenericArrayType a, java.lang.reflect.Type t) Learn whether t equals a.
private static boolean	equals(java.lang.reflect.ParameterizedType p, java.lang.reflect.Type t) Learn whether t equals p.
private static boolean	equals(java.lang.reflect.Type[] t1, java.lang.reflect.Type[] t2) Learn whether t1 equals t2.
static boolean	equals(java.lang.reflect.Type t1, java.lang.reflect.Type t2) Check equality of types.
private static boolean	equals(java.lang.reflect.WildcardType w, java.lang.reflect.Type t) Learn whether t equals w.
private static java.lang.reflect.Type[]	extractTypeArgumentsFrom(java.util.Map<java.lang.reflect.TypeVariable<?>,java.lang.reflect.Type> mappings, java.lang.reflect.TypeVariable<?>[] variables) Helper method to establish the formal parameters for a parameterized type.
private static int[]	findRecursiveTypes(java.lang.reflect.ParameterizedType p)
static java.lang.reflect.GenericArrayType	genericArrayType(java.lang.reflect.Type componentType) Create a generic array type instance.
private static java.lang.String	genericArrayTypeToString(java.lang.reflect.GenericArrayType g) Format a GenericArrayType as a String.
static java.lang.reflect.Type	getArrayComponentType(java.lang.reflect.Type type) Get the array component type of type.
private static java.lang.reflect.Type	getClosestParentType(java.lang.Class<?> cls, java.lang.Class<?> superClass) Get the closest parent type to the super class specified by superClass.
static java.lang.reflect.Type[]	getImplicitBounds(java.lang.reflect.TypeVariable<?> typeVariable) Returns an array containing the sole type of Object if TypeVariable.getBounds() returns an empty array.
static java.lang.reflect.Type[]	getImplicitLowerBounds(java.lang.reflect.WildcardType wildcardType) Returns an array containing a single value of null if WildcardType.getLowerBounds() returns an empty array.
static java.lang.reflect.Type[]	getImplicitUpperBounds(java.lang.reflect.WildcardType wildcardType) Returns an array containing the sole value of Object if WildcardType.getUpperBounds() returns an empty array.
private static java.lang.Class<?>	getRawType(java.lang.reflect.ParameterizedType parameterizedType) Transforms the passed in type to a Class object.
static java.lang.Class<?>	getRawType(java.lang.reflect.Type type, java.lang.reflect.Type assigningType) Get the raw type of a Java type, given its context.
private static java.util.Map<java.lang.reflect.TypeVariable<?>,java.lang.reflect.Type>	getTypeArguments(java.lang.Class<?> cls, java.lang.Class<?> toClass, java.util.Map<java.lang.reflect.TypeVariable<?>,java.lang.reflect.Type> subtypeVarAssigns) Return a map of the type arguments of a class in the context of toClass.
static java.util.Map<java.lang.reflect.TypeVariable<?>,java.lang.reflect.Type>	getTypeArguments(java.lang.reflect.ParameterizedType type) Retrieves all the type arguments for this parameterized type including owner hierarchy arguments such as Outer<K,V>.Inner<T>.DeepInner<E> .
private static java.util.Map<java.lang.reflect.TypeVariable<?>,java.lang.reflect.Type>	getTypeArguments(java.lang.reflect.ParameterizedType parameterizedType, java.lang.Class<?> toClass, java.util.Map<java.lang.reflect.TypeVariable<?>,java.lang.reflect.Type> subtypeVarAssigns) Return a map of the type arguments of a parameterized type in the context of toClass.
static java.util.Map<java.lang.reflect.TypeVariable<?>,java.lang.reflect.Type>	getTypeArguments(java.lang.reflect.Type type, java.lang.Class<?> toClass) Gets the type arguments of a class/interface based on a subtype.
private static java.util.Map<java.lang.reflect.TypeVariable<?>,java.lang.reflect.Type>	getTypeArguments(java.lang.reflect.Type type, java.lang.Class<?> toClass, java.util.Map<java.lang.reflect.TypeVariable<?>,java.lang.reflect.Type> subtypeVarAssigns) Return a map of the type arguments of type in the context of toClass.
static boolean	isArrayType(java.lang.reflect.Type type) Learn whether the specified type denotes an array type.
private static boolean	isAssignable(java.lang.reflect.Type type, java.lang.Class<?> toClass) Checks if the subject type may be implicitly cast to the target class following the Java generics rules.
private static boolean	isAssignable(java.lang.reflect.Type type, java.lang.reflect.GenericArrayType toGenericArrayType, java.util.Map<java.lang.reflect.TypeVariable<?>,java.lang.reflect.Type> typeVarAssigns) Checks if the subject type may be implicitly cast to the target generic array type following the Java generics rules.
private static boolean	isAssignable(java.lang.reflect.Type type, java.lang.reflect.ParameterizedType toParameterizedType, java.util.Map<java.lang.reflect.TypeVariable<?>,java.lang.reflect.Type> typeVarAssigns) Checks if the subject type may be implicitly cast to the target parameterized type following the Java generics rules.
static boolean	isAssignable(java.lang.reflect.Type type, java.lang.reflect.Type toType) Checks if the subject type may be implicitly cast to the target type following the Java generics rules.
private static boolean	isAssignable(java.lang.reflect.Type type, java.lang.reflect.Type toType, java.util.Map<java.lang.reflect.TypeVariable<?>,java.lang.reflect.Type> typeVarAssigns) Checks if the subject type may be implicitly cast to the target type following the Java generics rules.
private static boolean	isAssignable(java.lang.reflect.Type type, java.lang.reflect.TypeVariable<?> toTypeVariable, java.util.Map<java.lang.reflect.TypeVariable<?>,java.lang.reflect.Type> typeVarAssigns) Checks if the subject type may be implicitly cast to the target type variable following the Java generics rules.
private static boolean	isAssignable(java.lang.reflect.Type type, java.lang.reflect.WildcardType toWildcardType, java.util.Map<java.lang.reflect.TypeVariable<?>,java.lang.reflect.Type> typeVarAssigns) Checks if the subject type may be implicitly cast to the target wildcard type following the Java generics rules.
static boolean	isInstance(java.lang.Object value, java.lang.reflect.Type type) Checks if the given value can be assigned to the target type following the Java generics rules.
private static <T> void	mapTypeVariablesToArguments(java.lang.Class<T> cls, java.lang.reflect.ParameterizedType parameterizedType, java.util.Map<java.lang.reflect.TypeVariable<?>,java.lang.reflect.Type> typeVarAssigns) Performs a mapping of type variables.
static java.lang.reflect.Type[]	normalizeUpperBounds(java.lang.reflect.Type[] bounds) This method strips out the redundant upper bound types in type variable types and wildcard types (or it would with wildcard types if multiple upper bounds were allowed).
static java.lang.reflect.ParameterizedType	parameterize(java.lang.Class<?> raw, java.util.Map<java.lang.reflect.TypeVariable<?>,java.lang.reflect.Type> typeArgMappings) Create a parameterized type instance.
static java.lang.reflect.ParameterizedType	parameterize(java.lang.Class<?> raw, java.lang.reflect.Type... typeArguments) Create a parameterized type instance.
private static java.lang.String	parameterizedTypeToString(java.lang.reflect.ParameterizedType p) Format a ParameterizedType as a String.
static java.lang.reflect.ParameterizedType	parameterizeWithOwner(java.lang.reflect.Type owner, java.lang.Class<?> raw, java.util.Map<java.lang.reflect.TypeVariable<?>,java.lang.reflect.Type> typeArgMappings) Create a parameterized type instance.
static java.lang.reflect.ParameterizedType	parameterizeWithOwner(java.lang.reflect.Type owner, java.lang.Class<?> raw, java.lang.reflect.Type... typeArguments) Create a parameterized type instance.
private static java.lang.reflect.Type	substituteTypeVariables(java.lang.reflect.Type type, java.util.Map<java.lang.reflect.TypeVariable<?>,java.lang.reflect.Type> typeVarAssigns) Find the mapping for type in typeVarAssigns.
static java.lang.String	toLongString(java.lang.reflect.TypeVariable<?> var) Format a TypeVariable including its GenericDeclaration.
private static <T> java.lang.String	toString(T object)
static java.lang.String	toString(java.lang.reflect.Type type) Present a given type as a Java-esque String.
static boolean	typesSatisfyVariables(java.util.Map<java.lang.reflect.TypeVariable<?>,java.lang.reflect.Type> typeVarAssigns) Determines whether or not specified types satisfy the bounds of their mapped type variables.
private static java.lang.String	typeVariableToString(java.lang.reflect.TypeVariable<?> v) Format a TypeVariable as a String.
private static java.lang.reflect.Type[]	unrollBounds(java.util.Map<java.lang.reflect.TypeVariable<?>,java.lang.reflect.Type> typeArguments, java.lang.reflect.Type[] bounds) Local helper method to unroll variables in a type bounds array.
private static java.lang.reflect.Type	unrollVariableAssignments(java.lang.reflect.TypeVariable<?> var, java.util.Map<java.lang.reflect.TypeVariable<?>,java.lang.reflect.Type> typeVarAssigns) Look up var in typeVarAssigns transitively, i.e.
static java.lang.reflect.Type	unrollVariables(java.util.Map<java.lang.reflect.TypeVariable<?>,java.lang.reflect.Type> typeArguments, java.lang.reflect.Type type) Get a type representing type with variable assignments "unrolled."
static TypeUtils.WildcardTypeBuilder	wildcardType() Get a TypeUtils.WildcardTypeBuilder.
private static java.lang.String	wildcardTypeToString(java.lang.reflect.WildcardType w) Format a WildcardType as a String.
static <T> Typed<T>	wrap(java.lang.Class<T> type) Wrap the specified Class in a Typed wrapper.
static <T> Typed<T>	wrap(java.lang.reflect.Type type) Wrap the specified Type in a Typed wrapper.

Methods inherited from class java.lang.Object

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

Field Detail

WILDCARD_ALL

public static final java.lang.reflect.WildcardType WILDCARD_ALL

A wildcard instance matching ?.

Since:

3.2

Constructor Detail

TypeUtils

public TypeUtils()

TypeUtils instances should NOT be constructed in standard programming. Instead, the class should be used as TypeUtils.isAssignable(cls, toClass).

This constructor is public to permit tools that require a JavaBean instance to operate.

Method Detail

isAssignable

public static boolean isAssignable(java.lang.reflect.Type type,
                                   java.lang.reflect.Type toType)

Checks if the subject type may be implicitly cast to the target type following the Java generics rules. If both types are Class objects, the method returns the result of ClassUtils.isAssignable(Class, Class).

Parameters:

type - the subject type to be assigned to the target type

toType - the target type

Returns:

true if type is assignable to toType.

isAssignable

private static boolean isAssignable(java.lang.reflect.Type type,
                                    java.lang.reflect.Type toType,
                                    java.util.Map<java.lang.reflect.TypeVariable<?>,java.lang.reflect.Type> typeVarAssigns)

Checks if the subject type may be implicitly cast to the target type following the Java generics rules.

Parameters:

type - the subject type to be assigned to the target type

toType - the target type

typeVarAssigns - optional map of type variable assignments

Returns:

true if type is assignable to toType.

isAssignable

private static boolean isAssignable(java.lang.reflect.Type type,
                                    java.lang.Class<?> toClass)

Checks if the subject type may be implicitly cast to the target class following the Java generics rules.

Parameters:

type - the subject type to be assigned to the target type

toClass - the target class

Returns:

true if type is assignable to toClass.

isAssignable

private static boolean isAssignable(java.lang.reflect.Type type,
                                    java.lang.reflect.ParameterizedType toParameterizedType,
                                    java.util.Map<java.lang.reflect.TypeVariable<?>,java.lang.reflect.Type> typeVarAssigns)

Checks if the subject type may be implicitly cast to the target parameterized type following the Java generics rules.

Parameters:

type - the subject type to be assigned to the target type

toParameterizedType - the target parameterized type

typeVarAssigns - a map with type variables

Returns:

true if type is assignable to toType.

unrollVariableAssignments

private static java.lang.reflect.Type unrollVariableAssignments(java.lang.reflect.TypeVariable<?> var,
                                                                java.util.Map<java.lang.reflect.TypeVariable<?>,java.lang.reflect.Type> typeVarAssigns)

Look up var in typeVarAssigns transitively, i.e. keep looking until the value found is not a type variable.

Parameters:

var - the type variable to look up

typeVarAssigns - the map used for the look up

Returns:

Type or null if some variable was not in the map

Since:

3.2

isAssignable

private static boolean isAssignable(java.lang.reflect.Type type,
                                    java.lang.reflect.GenericArrayType toGenericArrayType,
                                    java.util.Map<java.lang.reflect.TypeVariable<?>,java.lang.reflect.Type> typeVarAssigns)

Checks if the subject type may be implicitly cast to the target generic array type following the Java generics rules.

Parameters:

type - the subject type to be assigned to the target type

toGenericArrayType - the target generic array type

typeVarAssigns - a map with type variables

Returns:

true if type is assignable to toGenericArrayType.

isAssignable

private static boolean isAssignable(java.lang.reflect.Type type,
                                    java.lang.reflect.WildcardType toWildcardType,
                                    java.util.Map<java.lang.reflect.TypeVariable<?>,java.lang.reflect.Type> typeVarAssigns)

Checks if the subject type may be implicitly cast to the target wildcard type following the Java generics rules.

Parameters:

type - the subject type to be assigned to the target type

toWildcardType - the target wildcard type

typeVarAssigns - a map with type variables

Returns:

true if type is assignable to toWildcardType.

isAssignable

private static boolean isAssignable(java.lang.reflect.Type type,
                                    java.lang.reflect.TypeVariable<?> toTypeVariable,
                                    java.util.Map<java.lang.reflect.TypeVariable<?>,java.lang.reflect.Type> typeVarAssigns)

Checks if the subject type may be implicitly cast to the target type variable following the Java generics rules.

Parameters:

type - the subject type to be assigned to the target type

toTypeVariable - the target type variable

typeVarAssigns - a map with type variables

Returns:

true if type is assignable to toTypeVariable.

substituteTypeVariables

private static java.lang.reflect.Type substituteTypeVariables(java.lang.reflect.Type type,
                                                              java.util.Map<java.lang.reflect.TypeVariable<?>,java.lang.reflect.Type> typeVarAssigns)

Find the mapping for type in typeVarAssigns.

Parameters:

type - the type to be replaced

typeVarAssigns - the map with type variables

Returns:

the replaced type

Throws:

java.lang.IllegalArgumentException - if the type cannot be substituted

getTypeArguments

public static java.util.Map<java.lang.reflect.TypeVariable<?>,java.lang.reflect.Type> getTypeArguments(java.lang.reflect.ParameterizedType type)

Retrieves all the type arguments for this parameterized type including owner hierarchy arguments such as Outer<K,V>.Inner<T>.DeepInner<E> . The arguments are returned in a Map specifying the argument type for each TypeVariable.

Parameters:

type - specifies the subject parameterized type from which to harvest the parameters.

Returns:

a Map of the type arguments to their respective type variables.

getTypeArguments

public static java.util.Map<java.lang.reflect.TypeVariable<?>,java.lang.reflect.Type> getTypeArguments(java.lang.reflect.Type type,
                                                                                                       java.lang.Class<?> toClass)

Gets the type arguments of a class/interface based on a subtype. For instance, this method will determine that both of the parameters for the interface Map are Object for the subtype Properties even though the subtype does not directly implement the Map interface.

This method returns null if type is not assignable to toClass. It returns an empty map if none of the classes or interfaces in its inheritance hierarchy specify any type arguments.

A side effect of this method is that it also retrieves the type arguments for the classes and interfaces that are part of the hierarchy between type and toClass. So with the above example, this method will also determine that the type arguments for Hashtable are also both Object. In cases where the interface specified by toClass is (indirectly) implemented more than once (e.g. where toClass specifies the interface Iterable and type specifies a parameterized type that implements both Set and Collection), this method will look at the inheritance hierarchy of only one of the implementations/subclasses; the first interface encountered that isn't a subinterface to one of the others in the type to toClass hierarchy.

Parameters:

type - the type from which to determine the type parameters of toClass

toClass - the class whose type parameters are to be determined based on the subtype type

Returns:

a Map of the type assignments for the type variables in each type in the inheritance hierarchy from type to toClass inclusive.

getTypeArguments

private static java.util.Map<java.lang.reflect.TypeVariable<?>,java.lang.reflect.Type> getTypeArguments(java.lang.reflect.Type type,
                                                                                                        java.lang.Class<?> toClass,
                                                                                                        java.util.Map<java.lang.reflect.TypeVariable<?>,java.lang.reflect.Type> subtypeVarAssigns)

Return a map of the type arguments of type in the context of toClass.

Parameters:

type - the type in question

toClass - the class

subtypeVarAssigns - a map with type variables

Returns:

the Map with type arguments

getTypeArguments

private static java.util.Map<java.lang.reflect.TypeVariable<?>,java.lang.reflect.Type> getTypeArguments(java.lang.reflect.ParameterizedType parameterizedType,
                                                                                                        java.lang.Class<?> toClass,
                                                                                                        java.util.Map<java.lang.reflect.TypeVariable<?>,java.lang.reflect.Type> subtypeVarAssigns)

Return a map of the type arguments of a parameterized type in the context of toClass.

Parameters:

parameterizedType - the parameterized type

toClass - the class

subtypeVarAssigns - a map with type variables

Returns:

the Map with type arguments

getTypeArguments

private static java.util.Map<java.lang.reflect.TypeVariable<?>,java.lang.reflect.Type> getTypeArguments(java.lang.Class<?> cls,
                                                                                                        java.lang.Class<?> toClass,
                                                                                                        java.util.Map<java.lang.reflect.TypeVariable<?>,java.lang.reflect.Type> subtypeVarAssigns)

Return a map of the type arguments of a class in the context of toClass.

Parameters:

cls - the class in question

toClass - the context class

subtypeVarAssigns - a map with type variables

Returns:

the Map with type arguments

determineTypeArguments

public static java.util.Map<java.lang.reflect.TypeVariable<?>,java.lang.reflect.Type> determineTypeArguments(java.lang.Class<?> cls,
                                                                                                             java.lang.reflect.ParameterizedType superType)

Tries to determine the type arguments of a class/interface based on a super parameterized type's type arguments. This method is the inverse of getTypeArguments(Type, Class) which gets a class/interface's type arguments based on a subtype. It is far more limited in determining the type arguments for the subject class's type variables in that it can only determine those parameters that map from the subject Class object to the supertype.

Example: TreeSet sets its parameter as the parameter for NavigableSet, which in turn sets the parameter of SortedSet, which in turn sets the parameter of Set, which in turn sets the parameter of Collection, which in turn sets the parameter of Iterable. Since TreeSet's parameter maps (indirectly) to Iterable's parameter, it will be able to determine that based on the super type Iterable<? extends Map<Integer, ? extends Collection<?>>>, the parameter of TreeSet is ? extends Map<Integer, ? extends Collection<?>>.

Parameters:

cls - the class whose type parameters are to be determined, not null

superType - the super type from which cls's type arguments are to be determined, not null

Returns:

a Map of the type assignments that could be determined for the type variables in each type in the inheritance hierarchy from type to toClass inclusive.

mapTypeVariablesToArguments

private static <T> void mapTypeVariablesToArguments(java.lang.Class<T> cls,
                                                    java.lang.reflect.ParameterizedType parameterizedType,
                                                    java.util.Map<java.lang.reflect.TypeVariable<?>,java.lang.reflect.Type> typeVarAssigns)

Performs a mapping of type variables.

Type Parameters:

T - the generic type of the class in question

Parameters:

cls - the class in question

parameterizedType - the parameterized type

typeVarAssigns - the map to be filled

getClosestParentType

private static java.lang.reflect.Type getClosestParentType(java.lang.Class<?> cls,
                                                           java.lang.Class<?> superClass)

Get the closest parent type to the super class specified by superClass.

Parameters:

cls - the class in question

superClass - the super class

Returns:

the closes parent type

isInstance

public static boolean isInstance(java.lang.Object value,
                                 java.lang.reflect.Type type)

Checks if the given value can be assigned to the target type following the Java generics rules.

Parameters:

value - the value to be checked

type - the target type

Returns:

true if value is an instance of type.

normalizeUpperBounds

public static java.lang.reflect.Type[] normalizeUpperBounds(java.lang.reflect.Type[] bounds)

This method strips out the redundant upper bound types in type variable types and wildcard types (or it would with wildcard types if multiple upper bounds were allowed).

Example, with the variable type declaration:

<K extends java.util.Collection<String> &
 java.util.List<String>>

since List is a subinterface of Collection, this method will return the bounds as if the declaration had been:

<K extends java.util.List<String>>

Parameters:

bounds - an array of types representing the upper bounds of either WildcardType or TypeVariable, not null.

Returns:

an array containing the values from bounds minus the redundant types.

getImplicitBounds

public static java.lang.reflect.Type[] getImplicitBounds(java.lang.reflect.TypeVariable<?> typeVariable)

Returns an array containing the sole type of Object if TypeVariable.getBounds() returns an empty array. Otherwise, it returns the result of TypeVariable.getBounds() passed into normalizeUpperBounds(java.lang.reflect.Type[]).

Parameters:

typeVariable - the subject type variable, not null

Returns:

a non-empty array containing the bounds of the type variable.

getImplicitUpperBounds

public static java.lang.reflect.Type[] getImplicitUpperBounds(java.lang.reflect.WildcardType wildcardType)

Returns an array containing the sole value of Object if WildcardType.getUpperBounds() returns an empty array. Otherwise, it returns the result of WildcardType.getUpperBounds() passed into normalizeUpperBounds(java.lang.reflect.Type[]).

Parameters:

wildcardType - the subject wildcard type, not null

Returns:

a non-empty array containing the upper bounds of the wildcard type.

getImplicitLowerBounds

public static java.lang.reflect.Type[] getImplicitLowerBounds(java.lang.reflect.WildcardType wildcardType)

Returns an array containing a single value of null if WildcardType.getLowerBounds() returns an empty array. Otherwise, it returns the result of WildcardType.getLowerBounds().

Parameters:

wildcardType - the subject wildcard type, not null

Returns:

a non-empty array containing the lower bounds of the wildcard type.

typesSatisfyVariables

public static boolean typesSatisfyVariables(java.util.Map<java.lang.reflect.TypeVariable<?>,java.lang.reflect.Type> typeVarAssigns)

Determines whether or not specified types satisfy the bounds of their mapped type variables. When a type parameter extends another (such as <T, S extends T>), uses another as a type parameter (such as <T, S extends Comparable>>), or otherwise depends on another type variable to be specified, the dependencies must be included in typeVarAssigns.

Parameters:

typeVarAssigns - specifies the potential types to be assigned to the type variables, not null.

Returns:

whether or not the types can be assigned to their respective type variables.

getRawType

private static java.lang.Class<?> getRawType(java.lang.reflect.ParameterizedType parameterizedType)

Transforms the passed in type to a Class object. Type-checking method of convenience.

Parameters:

parameterizedType - the type to be converted

Returns:

the corresponding Class object

Throws:

java.lang.IllegalStateException - if the conversion fails

getRawType

public static java.lang.Class<?> getRawType(java.lang.reflect.Type type,
                                            java.lang.reflect.Type assigningType)

Get the raw type of a Java type, given its context. Primarily for use with TypeVariables and GenericArrayTypes, or when you do not know the runtime type of type: if you know you have a Class instance, it is already raw; if you know you have a ParameterizedType, its raw type is only a method call away.

Parameters:

type - to resolve

assigningType - type to be resolved against

Returns:

the resolved Class object or null if the type could not be resolved

isArrayType

public static boolean isArrayType(java.lang.reflect.Type type)

Learn whether the specified type denotes an array type.

Parameters:

type - the type to be checked

Returns:

true if type is an array class or a GenericArrayType.

getArrayComponentType

public static java.lang.reflect.Type getArrayComponentType(java.lang.reflect.Type type)

Get the array component type of type.

Parameters:

type - the type to be checked

Returns:

component type or null if type is not an array type

unrollVariables

public static java.lang.reflect.Type unrollVariables(java.util.Map<java.lang.reflect.TypeVariable<?>,java.lang.reflect.Type> typeArguments,
                                                     java.lang.reflect.Type type)

Get a type representing type with variable assignments "unrolled."

Parameters:

typeArguments - as from getTypeArguments(Type, Class)

type - the type to unroll variable assignments for

Returns:

Type

Since:

3.2

unrollBounds

private static java.lang.reflect.Type[] unrollBounds(java.util.Map<java.lang.reflect.TypeVariable<?>,java.lang.reflect.Type> typeArguments,
                                                     java.lang.reflect.Type[] bounds)

Local helper method to unroll variables in a type bounds array.

Parameters:

typeArguments - assignments Map

bounds - in which to expand variables

Returns:

bounds with any variables reassigned

Since:

3.2

containsTypeVariables

public static boolean containsTypeVariables(java.lang.reflect.Type type)

Learn, recursively, whether any of the type parameters associated with type are bound to variables.

Parameters:

type - the type to check for type variables

Returns:

boolean

Since:

3.2

parameterize

public static final java.lang.reflect.ParameterizedType parameterize(java.lang.Class<?> raw,
                                                                     java.lang.reflect.Type... typeArguments)

Create a parameterized type instance.

Parameters:

raw - the raw class to create a parameterized type instance for

typeArguments - the types used for parameterization

Returns:

ParameterizedType

Since:

3.2

parameterize

public static final java.lang.reflect.ParameterizedType parameterize(java.lang.Class<?> raw,
                                                                     java.util.Map<java.lang.reflect.TypeVariable<?>,java.lang.reflect.Type> typeArgMappings)

Create a parameterized type instance.

Parameters:

raw - the raw class to create a parameterized type instance for

typeArgMappings - the mapping used for parameterization

Returns:

ParameterizedType

Since:

3.2

parameterizeWithOwner

public static final java.lang.reflect.ParameterizedType parameterizeWithOwner(java.lang.reflect.Type owner,
                                                                              java.lang.Class<?> raw,
                                                                              java.lang.reflect.Type... typeArguments)

Create a parameterized type instance.

Parameters:

owner - the owning type

raw - the raw class to create a parameterized type instance for

typeArguments - the types used for parameterization

Returns:

ParameterizedType

Since:

3.2

parameterizeWithOwner

public static final java.lang.reflect.ParameterizedType parameterizeWithOwner(java.lang.reflect.Type owner,
                                                                              java.lang.Class<?> raw,
                                                                              java.util.Map<java.lang.reflect.TypeVariable<?>,java.lang.reflect.Type> typeArgMappings)

Create a parameterized type instance.

Parameters:

owner - the owning type

raw - the raw class to create a parameterized type instance for

typeArgMappings - the mapping used for parameterization

Returns:

ParameterizedType

Since:

3.2

extractTypeArgumentsFrom

private static java.lang.reflect.Type[] extractTypeArgumentsFrom(java.util.Map<java.lang.reflect.TypeVariable<?>,java.lang.reflect.Type> mappings,
                                                                 java.lang.reflect.TypeVariable<?>[] variables)

Helper method to establish the formal parameters for a parameterized type.

Parameters:

mappings - map containing the assignments

variables - expected map keys

Returns:

array of map values corresponding to specified keys

wildcardType

public static TypeUtils.WildcardTypeBuilder wildcardType()

Get a TypeUtils.WildcardTypeBuilder.

Returns:

TypeUtils.WildcardTypeBuilder

Since:

3.2

genericArrayType

public static java.lang.reflect.GenericArrayType genericArrayType(java.lang.reflect.Type componentType)

Create a generic array type instance.

Parameters:

componentType - the type of the elements of the array. For example the component type of boolean[] is boolean

Returns:

GenericArrayType

Since:

3.2

equals

public static boolean equals(java.lang.reflect.Type t1,
                             java.lang.reflect.Type t2)

Check equality of types.

Parameters:

t1 - the first type

t2 - the second type

Returns:

boolean

Since:

3.2

equals

private static boolean equals(java.lang.reflect.ParameterizedType p,
                              java.lang.reflect.Type t)

Learn whether t equals p.

Parameters:

p - LHS

t - RHS

Returns:

boolean

Since:

3.2

equals

private static boolean equals(java.lang.reflect.GenericArrayType a,
                              java.lang.reflect.Type t)

Learn whether t equals a.

Parameters:

a - LHS

t - RHS

Returns:

boolean

Since:

3.2

equals

private static boolean equals(java.lang.reflect.WildcardType w,
                              java.lang.reflect.Type t)

Learn whether t equals w.

Parameters:

w - LHS

t - RHS

Returns:

boolean

Since:

3.2

equals

private static boolean equals(java.lang.reflect.Type[] t1,
                              java.lang.reflect.Type[] t2)

Learn whether t1 equals t2.

Parameters:

t1 - LHS

t2 - RHS

Returns:

boolean

Since:

3.2

toString

public static java.lang.String toString(java.lang.reflect.Type type)

Present a given type as a Java-esque String.

Parameters:

type - the type to create a String representation for, not null

Returns:

String

Since:

3.2

toLongString

public static java.lang.String toLongString(java.lang.reflect.TypeVariable<?> var)

Format a TypeVariable including its GenericDeclaration.

Parameters:

var - the type variable to create a String representation for, not null

Returns:

String

Since:

3.2

wrap

public static <T> Typed<T> wrap(java.lang.reflect.Type type)

Wrap the specified Type in a Typed wrapper.

Type Parameters:

T - inferred generic type

Parameters:

type - to wrap

Returns:

Typed<T>

Since:

3.2

wrap

public static <T> Typed<T> wrap(java.lang.Class<T> type)

Wrap the specified Class in a Typed wrapper.

Type Parameters:

T - generic type

Parameters:

type - to wrap

Returns:

Typed<T>

Since:

3.2

classToString

private static java.lang.String classToString(java.lang.Class<?> c)

Format a Class as a String.

Parameters:

c - Class to format

Returns:

String

Since:

3.2

typeVariableToString

private static java.lang.String typeVariableToString(java.lang.reflect.TypeVariable<?> v)

Format a TypeVariable as a String.

Parameters:

v - TypeVariable to format

Returns:

String

Since:

3.2

parameterizedTypeToString

private static java.lang.String parameterizedTypeToString(java.lang.reflect.ParameterizedType p)

Format a ParameterizedType as a String.

Parameters:

p - ParameterizedType to format

Returns:

String

Since:

3.2

appendRecursiveTypes

private static void appendRecursiveTypes(java.lang.StringBuilder buf,
                                         int[] recursiveTypeIndexes,
                                         java.lang.reflect.Type[] argumentTypes)

findRecursiveTypes

private static int[] findRecursiveTypes(java.lang.reflect.ParameterizedType p)

containsVariableTypeSameParametrizedTypeBound

private static boolean containsVariableTypeSameParametrizedTypeBound(java.lang.reflect.TypeVariable<?> typeVariable,
                                                                     java.lang.reflect.ParameterizedType p)

wildcardTypeToString

private static java.lang.String wildcardTypeToString(java.lang.reflect.WildcardType w)

Format a WildcardType as a String.

Parameters:

w - WildcardType to format

Returns:

String

Since:

3.2

genericArrayTypeToString

private static java.lang.String genericArrayTypeToString(java.lang.reflect.GenericArrayType g)

Format a GenericArrayType as a String.

Parameters:

g - GenericArrayType to format

Returns:

String

Since:

3.2

appendAllTo

private static <T> java.lang.StringBuilder appendAllTo(java.lang.StringBuilder buf,
                                                       java.lang.String sep,
                                                       T... types)

Append types to buf with separator sep.

Parameters:

buf - destination

sep - separator

types - to append

Returns:

buf

Since:

3.2

toString

private static <T> java.lang.String toString(T object)