com.google.auto.common

Class MoreTypes

java.lang.Object

com.google.auto.common.MoreTypes

public final class MoreTypes
extends java.lang.Object

Utilities related to TypeMirror instances.

Since:

2.0

Author:

Gregory Kick

Method Summary

Modifier and Type	Method and Description
static javax.lang.model.type.ArrayType	asArray(javax.lang.model.type.TypeMirror maybeArrayType) Returns a ArrayType if the TypeMirror represents an array or throws an IllegalArgumentException.
static javax.lang.model.type.DeclaredType	asDeclared(javax.lang.model.type.TypeMirror maybeDeclaredType) Returns a DeclaredType if the TypeMirror represents a declared type such as a class, interface, union/compound, or enum or throws an IllegalArgumentException.
static javax.lang.model.element.Element	asElement(javax.lang.model.type.TypeMirror typeMirror) An alternate implementation of Types.asElement(javax.lang.model.type.TypeMirror) that does not require a Types instance with the notable difference that it will throw IllegalArgumentException instead of returning null if the TypeMirror can not be converted to an Element.
static javax.lang.model.type.ErrorType	asError(javax.lang.model.type.TypeMirror maybeErrorType) Returns a ExecutableType if the TypeMirror represents an executable type such as may result from missing code, or bad compiles or throws an IllegalArgumentException.
static javax.lang.model.type.ExecutableType	asExecutable(javax.lang.model.type.TypeMirror maybeExecutableType) Returns a ExecutableType if the TypeMirror represents an executable type such as a method, constructor, or initializer or throws an IllegalArgumentException.
static javax.lang.model.type.IntersectionType	asIntersection(javax.lang.model.type.TypeMirror maybeIntersectionType) Returns an IntersectionType if the TypeMirror represents an intersection-type or throws an IllegalArgumentException.
static javax.lang.model.type.TypeMirror	asMemberOf(javax.lang.model.util.Types types, javax.lang.model.type.DeclaredType container, javax.lang.model.element.VariableElement variable) Resolves a VariableElement parameter to a method or constructor based on the given container, or a member of a class.
static javax.lang.model.type.NoType	asNoType(javax.lang.model.type.TypeMirror maybeNoType) Returns a NoType if the TypeMirror represents an non-type such as void, or package, etc.
static javax.lang.model.type.NullType	asNullType(javax.lang.model.type.TypeMirror maybeNullType) Returns a NullType if the TypeMirror represents the null type or throws an IllegalArgumentException.
static javax.lang.model.type.PrimitiveType	asPrimitiveType(javax.lang.model.type.TypeMirror maybePrimitiveType) Returns a PrimitiveType if the TypeMirror represents a primitive type or throws an IllegalArgumentException.
static javax.lang.model.element.TypeElement	asTypeElement(javax.lang.model.type.TypeMirror mirror)
static com.google.common.collect.ImmutableSet<javax.lang.model.element.TypeElement>	asTypeElements(java.lang.Iterable<? extends javax.lang.model.type.TypeMirror> mirrors)
static javax.lang.model.type.TypeVariable	asTypeVariable(javax.lang.model.type.TypeMirror maybeTypeVariable) Returns a TypeVariable if the TypeMirror represents a type variable or throws an IllegalArgumentException.
static javax.lang.model.type.WildcardType	asWildcard(javax.lang.model.type.TypeMirror maybeWildcardType) Returns a WildcardType if the TypeMirror represents a wildcard type or throws an IllegalArgumentException.
static com.google.common.base.Equivalence<javax.lang.model.type.TypeMirror>	equivalence() Returns an Equivalence that can be used to compare types.
static boolean	isConversionFromObjectUnchecked(javax.lang.model.type.TypeMirror type) Returns true if casting Object to the given type will elicit an unchecked warning from the compiler.
static boolean	isType(javax.lang.model.type.TypeMirror type) Returns true if the raw type underlying the given TypeMirror represents a type that can be referenced by a Class.
static boolean	isTypeOf(java.lang.Class<?> clazz, javax.lang.model.type.TypeMirror type) Returns true if the raw type underlying the given TypeMirror represents the same raw type as the given Class and throws an IllegalArgumentException if the TypeMirror does not represent a type that can be referenced by a Class
static com.google.common.base.Optional<javax.lang.model.type.DeclaredType>	nonObjectSuperclass(javax.lang.model.util.Types types, javax.lang.model.util.Elements elements, javax.lang.model.type.DeclaredType type) Returns the superclass of type, with any type parameters bound by type, or Optional.absent() if type is an interface or Object or its superclass is Object.
static com.google.common.collect.ImmutableSet<javax.lang.model.element.TypeElement>	referencedTypes(javax.lang.model.type.TypeMirror type) Returns the set of types that are referenced by the given TypeMirror.

Methods inherited from class java.lang.Object

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

Method Detail

equivalence

public static com.google.common.base.Equivalence<javax.lang.model.type.TypeMirror> equivalence()

Returns an Equivalence that can be used to compare types. The standard way to compare types is Types.isSameType, but this alternative may be preferred in a number of cases:

• If you don't have an instance of Types.
• If you want a reliable hashCode() for the types, for example to construct a set of types using HashSet with Equivalence.wrap(Object).
• If you want distinct type variables to be considered equal if they have the same names and bounds.
• If you want wildcard types to compare equal if they have the same bounds. Types.isSameType never considers wildcards equal, even when comparing a type to itself.

referencedTypes

public static com.google.common.collect.ImmutableSet<javax.lang.model.element.TypeElement> referencedTypes(javax.lang.model.type.TypeMirror type)

Returns the set of types that are referenced by the given TypeMirror.

asElement

public static javax.lang.model.element.Element asElement(javax.lang.model.type.TypeMirror typeMirror)

An alternate implementation of Types.asElement(javax.lang.model.type.TypeMirror) that does not require a Types instance with the notable difference that it will throw IllegalArgumentException instead of returning null if the TypeMirror can not be converted to an Element.

Throws:

java.lang.NullPointerException - if typeMirror is null

java.lang.IllegalArgumentException - if typeMirror cannot be converted to an Element

asTypeElement

public static javax.lang.model.element.TypeElement asTypeElement(javax.lang.model.type.TypeMirror mirror)

asTypeElements

public static com.google.common.collect.ImmutableSet<javax.lang.model.element.TypeElement> asTypeElements(java.lang.Iterable<? extends javax.lang.model.type.TypeMirror> mirrors)

asArray

public static javax.lang.model.type.ArrayType asArray(javax.lang.model.type.TypeMirror maybeArrayType)

Returns a ArrayType if the TypeMirror represents an array or throws an IllegalArgumentException.

asDeclared

public static javax.lang.model.type.DeclaredType asDeclared(javax.lang.model.type.TypeMirror maybeDeclaredType)

Returns a DeclaredType if the TypeMirror represents a declared type such as a class, interface, union/compound, or enum or throws an IllegalArgumentException.

asError

public static javax.lang.model.type.ErrorType asError(javax.lang.model.type.TypeMirror maybeErrorType)

Returns a ExecutableType if the TypeMirror represents an executable type such as may result from missing code, or bad compiles or throws an IllegalArgumentException.

asExecutable

public static javax.lang.model.type.ExecutableType asExecutable(javax.lang.model.type.TypeMirror maybeExecutableType)

Returns a ExecutableType if the TypeMirror represents an executable type such as a method, constructor, or initializer or throws an IllegalArgumentException.

asIntersection

public static javax.lang.model.type.IntersectionType asIntersection(javax.lang.model.type.TypeMirror maybeIntersectionType)

Returns an IntersectionType if the TypeMirror represents an intersection-type or throws an IllegalArgumentException.

asNoType

public static javax.lang.model.type.NoType asNoType(javax.lang.model.type.TypeMirror maybeNoType)

Returns a NoType if the TypeMirror represents an non-type such as void, or package, etc. or throws an IllegalArgumentException.

asNullType

public static javax.lang.model.type.NullType asNullType(javax.lang.model.type.TypeMirror maybeNullType)

Returns a NullType if the TypeMirror represents the null type or throws an IllegalArgumentException.

asPrimitiveType

public static javax.lang.model.type.PrimitiveType asPrimitiveType(javax.lang.model.type.TypeMirror maybePrimitiveType)

Returns a PrimitiveType if the TypeMirror represents a primitive type or throws an IllegalArgumentException.

asTypeVariable

public static javax.lang.model.type.TypeVariable asTypeVariable(javax.lang.model.type.TypeMirror maybeTypeVariable)

Returns a TypeVariable if the TypeMirror represents a type variable or throws an IllegalArgumentException.

asWildcard

public static javax.lang.model.type.WildcardType asWildcard(javax.lang.model.type.TypeMirror maybeWildcardType)

Returns a WildcardType if the TypeMirror represents a wildcard type or throws an IllegalArgumentException.

isType

public static boolean isType(javax.lang.model.type.TypeMirror type)

Returns true if the raw type underlying the given TypeMirror represents a type that can be referenced by a Class. If this returns true, then isTypeOf(java.lang.Class<?>, javax.lang.model.type.TypeMirror) is guaranteed to not throw.

isTypeOf

public static boolean isTypeOf(java.lang.Class<?> clazz,
                               javax.lang.model.type.TypeMirror type)

Returns true if the raw type underlying the given TypeMirror represents the same raw type as the given Class and throws an IllegalArgumentException if the TypeMirror does not represent a type that can be referenced by a Class

nonObjectSuperclass

public static com.google.common.base.Optional<javax.lang.model.type.DeclaredType> nonObjectSuperclass(javax.lang.model.util.Types types,
                                                                                                      javax.lang.model.util.Elements elements,
                                                                                                      javax.lang.model.type.DeclaredType type)

Returns the superclass of type, with any type parameters bound by type, or Optional.absent() if type is an interface or Object or its superclass is Object.

asMemberOf

public static javax.lang.model.type.TypeMirror asMemberOf(javax.lang.model.util.Types types,
                                                          javax.lang.model.type.DeclaredType container,
                                                          javax.lang.model.element.VariableElement variable)

Resolves a VariableElement parameter to a method or constructor based on the given container, or a member of a class. For parameters to a method or constructor, the variable's enclosing element must be a supertype of the container type. For example, given a container of type Set<String>, and a variable corresponding to the E e parameter in the Set.add(E e) method, this will return a TypeMirror for String.

isConversionFromObjectUnchecked

public static boolean isConversionFromObjectUnchecked(javax.lang.model.type.TypeMirror type)

Returns true if casting Object to the given type will elicit an unchecked warning from the compiler. Only type variables and parameterized types such as List<String> produce such warnings. There will be no warning if the type's only type parameters are simple wildcards, as in Map<?, ?>.