/* * Copyright (c) 2005, 2013, Oracle and/or its affiliates. All rights reserved. * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. * * This code is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License version 2 only, as * published by the Free Software Foundation. Oracle designates this * particular file as subject to the "Classpath" exception as provided * by Oracle in the LICENSE file that accompanied this code. * * This code is distributed in the hope that it will be useful, but WITHOUT * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License * version 2 for more details (a copy is included in the LICENSE file that * accompanied this code). * * You should have received a copy of the GNU General Public License version * 2 along with this work; if not, write to the Free Software Foundation, * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. * * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA * or visit www.oracle.com if you need additional information or have any * questions. */ package javax.lang.model.util; import java.lang.annotation.Annotation; import java.lang.annotation.AnnotationTypeMismatchException; import java.lang.annotation.IncompleteAnnotationException; import java.util.List; import javax.lang.model.element.*; import javax.lang.model.type.*; /** * Utility methods for operating on types. * *
Compatibility Note: Methods may be added to this interface * in future releases of the platform. * * @author Joseph D. Darcy * @author Scott Seligman * @author Peter von der Ahé * @see javax.annotation.processing.ProcessingEnvironment#getTypeUtils * @since 1.6 */ public interface Types { /** * Returns the element corresponding to a type. * The type may be a {@code DeclaredType} or {@code TypeVariable}. * Returns {@code null} if the type is not one with a * corresponding element. * * @param t the type to map to an element * @return the element corresponding to the given type */ Element asElement(TypeMirror t); /** * Tests whether two {@code TypeMirror} objects represent the same type. * *
Caveat: if either of the arguments to this method represents a * wildcard, this method will return false. As a consequence, a wildcard * is not the same type as itself. This might be surprising at first, * but makes sense once you consider that an example like this must be * rejected by the compiler: *
* {@code List> list = new ArrayList* *
Since annotations are only meta-data associated with a type,
* the set of annotations on either argument is not taken
* into account when computing whether or not two {@code
* TypeMirror} objects are the same type. In particular, two
* {@code TypeMirror} objects can have different annotations and
* still be considered the same.
*
* @param t1 the first type
* @param t2 the second type
* @return {@code true} if and only if the two types are the same
*/
boolean isSameType(TypeMirror t1, TypeMirror t2);
/**
* Tests whether one type is a subtype of another.
* Any type is considered to be a subtype of itself.
*
* @param t1 the first type
* @param t2 the second type
* @return {@code true} if and only if the first type is a subtype
* of the second
* @throws IllegalArgumentException if given a type for an executable, package, or module
* @jls 4.10 Subtyping
*/
boolean isSubtype(TypeMirror t1, TypeMirror t2);
/**
* Tests whether one type is assignable to another.
*
* @param t1 the first type
* @param t2 the second type
* @return {@code true} if and only if the first type is assignable
* to the second
* @throws IllegalArgumentException if given a type for an executable, package, or module
* @jls 5.2 Assignment Conversion
*/
boolean isAssignable(TypeMirror t1, TypeMirror t2);
/**
* Tests whether one type argument contains another.
*
* @param t1 the first type
* @param t2 the second type
* @return {@code true} if and only if the first type contains the second
* @throws IllegalArgumentException if given a type for an executable, package, or module
* @jls 4.5.1.1 Type Argument Containment and Equivalence
*/
boolean contains(TypeMirror t1, TypeMirror t2);
/**
* Tests whether the signature of one method is a subsignature
* of another.
*
* @param m1 the first method
* @param m2 the second method
* @return {@code true} if and only if the first signature is a
* subsignature of the second
* @jls 8.4.2 Method Signature
*/
boolean isSubsignature(ExecutableType m1, ExecutableType m2);
/**
* Returns the direct supertypes of a type. The interface types, if any,
* will appear last in the list. For an interface type with no direct
* super-interfaces, a type mirror representing {@code java.lang.Object}
* is returned.
*
* @param t the type being examined
* @return the direct supertypes, or an empty list if none
* @throws IllegalArgumentException if given a type for an executable, package, or module
* @jls 4.10 Subtyping
*/
List extends TypeMirror> directSupertypes(TypeMirror t);
/**
* Returns the erasure of a type.
*
* @param t the type to be erased
* @return the erasure of the given type
* @throws IllegalArgumentException if given a package type
* @jls 4.6 Type Erasure
*/
TypeMirror erasure(TypeMirror t);
/**
* Returns the class of a boxed value of a given primitive type.
* That is, boxing conversion is applied.
*
* @param p the primitive type to be converted
* @return the class of a boxed value of type {@code p}
* @jls 5.1.7 Boxing Conversion
*/
TypeElement boxedClass(PrimitiveType p);
/**
* Returns the type (a primitive type) of unboxed values of a given type.
* That is, unboxing conversion is applied.
*
* @param t the type to be unboxed
* @return the type of an unboxed value of type {@code t}
* @throws IllegalArgumentException if the given type has no
* unboxing conversion
* @jls 5.1.8 Unboxing Conversion
*/
PrimitiveType unboxedType(TypeMirror t);
/**
* Applies capture conversion to a type.
*
* @param t the type to be converted
* @return the result of applying capture conversion
* @throws IllegalArgumentException if given a type for an executable, package, or module
* @jls 5.1.10 Capture Conversion
*/
TypeMirror capture(TypeMirror t);
/**
* Returns a primitive type.
*
* @param kind the kind of primitive type to return
* @return a primitive type
* @throws IllegalArgumentException if {@code kind} is not a primitive kind
*/
PrimitiveType getPrimitiveType(TypeKind kind);
/**
* Returns the null type. This is the type of {@code null}.
*
* @return the null type
*/
NullType getNullType();
/**
* Returns a pseudo-type used where no actual type is appropriate.
* The kind of type to return may be either
* {@link TypeKind#VOID VOID} or {@link TypeKind#NONE NONE}.
* For packages, use
* {@link Elements#getPackageElement(CharSequence)}{@code .asType()}
* instead.
*
* @param kind the kind of type to return
* @return a pseudo-type of kind {@code VOID} or {@code NONE}
* @throws IllegalArgumentException if {@code kind} is not valid
*/
NoType getNoType(TypeKind kind);
/**
* Returns an array type with the specified component type.
*
* @param componentType the component type
* @return an array type with the specified component type.
* @throws IllegalArgumentException if the component type is not valid for
* an array
*/
ArrayType getArrayType(TypeMirror componentType);
/**
* Returns a new wildcard type argument. Either of the wildcard's
* bounds may be specified, or neither, but not both.
*
* @param extendsBound the extends (upper) bound, or {@code null} if none
* @param superBound the super (lower) bound, or {@code null} if none
* @return a new wildcard
* @throws IllegalArgumentException if bounds are not valid
*/
WildcardType getWildcardType(TypeMirror extendsBound,
TypeMirror superBound);
/**
* Returns the type corresponding to a type element and
* actual type arguments.
* Given the type element for {@code Set} and the type mirror
* for {@code String},
* for example, this method may be used to get the
* parameterized type {@code Set The number of type arguments must either equal the
* number of the type element's formal type parameters, or must be
* zero. If zero, and if the type element is generic,
* then the type element's raw type is returned.
*
* If a parameterized type is being returned, its type element
* must not be contained within a generic outer class.
* The parameterized type {@code Outer If the containing type is a parameterized type,
* the number of type arguments must equal the
* number of {@code typeElem}'s formal type parameters.
* If it is not parameterized or if it is {@code null}, this method is
* equivalent to {@code getDeclaredType(typeElem, typeArgs)}.
*
* @param containing the containing type, or {@code null} if none
* @param typeElem the type element
* @param typeArgs the actual type arguments
* @return the type corresponding to the type element and
* actual type arguments, contained within the given type
* @throws IllegalArgumentException if too many or too few
* type arguments are given, or if an inappropriate type
* argument, type element, or containing type is provided
*/
DeclaredType getDeclaredType(DeclaredType containing,
TypeElement typeElem, TypeMirror... typeArgs);
/**
* Returns the type of an element when that element is viewed as
* a member of, or otherwise directly contained by, a given type.
* For example,
* when viewed as a member of the parameterized type {@code Set