aoqi@0: /*
aoqi@0:  * Copyright (c) 2010, 2013, Oracle and/or its affiliates. All rights reserved.
aoqi@0:  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
aoqi@0:  *
aoqi@0:  * This code is free software; you can redistribute it and/or modify it
aoqi@0:  * under the terms of the GNU General Public License version 2 only, as
aoqi@0:  * published by the Free Software Foundation.  Oracle designates this
aoqi@0:  * particular file as subject to the "Classpath" exception as provided
aoqi@0:  * by Oracle in the LICENSE file that accompanied this code.
aoqi@0:  *
aoqi@0:  * This code is distributed in the hope that it will be useful, but WITHOUT
aoqi@0:  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
aoqi@0:  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
aoqi@0:  * version 2 for more details (a copy is included in the LICENSE file that
aoqi@0:  * accompanied this code).
aoqi@0:  *
aoqi@0:  * You should have received a copy of the GNU General Public License version
aoqi@0:  * 2 along with this work; if not, write to the Free Software Foundation,
aoqi@0:  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
aoqi@0:  *
aoqi@0:  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
aoqi@0:  * or visit www.oracle.com if you need additional information or have any
aoqi@0:  * questions.
aoqi@0:  */
aoqi@0: 
aoqi@0: /*
aoqi@0:  * This file is available under and governed by the GNU General Public
aoqi@0:  * License version 2 only, as published by the Free Software Foundation.
aoqi@0:  * However, the following notice accompanied the original version of this
aoqi@0:  * file, and Oracle licenses the original version of this file under the BSD
aoqi@0:  * license:
aoqi@0:  */
aoqi@0: /*
aoqi@0:    Copyright 2009-2013 Attila Szegedi
aoqi@0: 
aoqi@0:    Licensed under both the Apache License, Version 2.0 (the "Apache License")
aoqi@0:    and the BSD License (the "BSD License"), with licensee being free to
aoqi@0:    choose either of the two at their discretion.
aoqi@0: 
aoqi@0:    You may not use this file except in compliance with either the Apache
aoqi@0:    License or the BSD License.
aoqi@0: 
aoqi@0:    If you choose to use this file in compliance with the Apache License, the
aoqi@0:    following notice applies to you:
aoqi@0: 
aoqi@0:        You may obtain a copy of the Apache License at
aoqi@0: 
aoqi@0:            http://www.apache.org/licenses/LICENSE-2.0
aoqi@0: 
aoqi@0:        Unless required by applicable law or agreed to in writing, software
aoqi@0:        distributed under the License is distributed on an "AS IS" BASIS,
aoqi@0:        WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
aoqi@0:        implied. See the License for the specific language governing
aoqi@0:        permissions and limitations under the License.
aoqi@0: 
aoqi@0:    If you choose to use this file in compliance with the BSD License, the
aoqi@0:    following notice applies to you:
aoqi@0: 
aoqi@0:        Redistribution and use in source and binary forms, with or without
aoqi@0:        modification, are permitted provided that the following conditions are
aoqi@0:        met:
aoqi@0:        * Redistributions of source code must retain the above copyright
aoqi@0:          notice, this list of conditions and the following disclaimer.
aoqi@0:        * Redistributions in binary form must reproduce the above copyright
aoqi@0:          notice, this list of conditions and the following disclaimer in the
aoqi@0:          documentation and/or other materials provided with the distribution.
aoqi@0:        * Neither the name of the copyright holder nor the names of
aoqi@0:          contributors may be used to endorse or promote products derived from
aoqi@0:          this software without specific prior written permission.
aoqi@0: 
aoqi@0:        THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS
aoqi@0:        IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
aoqi@0:        TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
aoqi@0:        PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL COPYRIGHT HOLDER
aoqi@0:        BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
aoqi@0:        CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
aoqi@0:        SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
aoqi@0:        BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
aoqi@0:        WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
aoqi@0:        OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
aoqi@0:        ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
aoqi@0: */
aoqi@0: 
aoqi@0: package jdk.internal.dynalink.support;
aoqi@0: 
aoqi@0: import java.util.ArrayList;
aoqi@0: import java.util.Collection;
aoqi@0: import java.util.Collections;
aoqi@0: import java.util.HashMap;
aoqi@0: import java.util.HashSet;
aoqi@0: import java.util.IdentityHashMap;
aoqi@0: import java.util.Iterator;
aoqi@0: import java.util.List;
aoqi@0: import java.util.Map;
aoqi@0: import java.util.Set;
aoqi@0: 
aoqi@0: /**
aoqi@0:  * Various static utility methods for testing type relationships.
aoqi@0:  *
aoqi@0:  * @author Attila Szegedi
aoqi@0:  */
aoqi@0: public class TypeUtilities {
aoqi@0:     static final Class<Object> OBJECT_CLASS = Object.class;
aoqi@0: 
aoqi@0:     private TypeUtilities() {
aoqi@0:     }
aoqi@0: 
aoqi@0:     /**
aoqi@0:      * Given two types represented by c1 and c2, returns a type that is their most specific common superclass or
aoqi@0:      * superinterface.
aoqi@0:      *
aoqi@0:      * @param c1 one type
aoqi@0:      * @param c2 another type
aoqi@0:      * @return their most common superclass or superinterface. If they have several unrelated superinterfaces as their
aoqi@0:      * most specific common type, or the types themselves are completely unrelated interfaces, {@link java.lang.Object}
aoqi@0:      * is returned.
aoqi@0:      */
aoqi@0:     public static Class<?> getMostSpecificCommonType(Class<?> c1, Class<?> c2) {
aoqi@0:         if(c1 == c2) {
aoqi@0:             return c1;
aoqi@0:         }
aoqi@0:         Class<?> c3 = c2;
aoqi@0:         if(c3.isPrimitive()) {
aoqi@0:             if(c3 == Byte.TYPE)
aoqi@0:                 c3 = Byte.class;
aoqi@0:             else if(c3 == Short.TYPE)
aoqi@0:                 c3 = Short.class;
aoqi@0:             else if(c3 == Character.TYPE)
aoqi@0:                 c3 = Character.class;
aoqi@0:             else if(c3 == Integer.TYPE)
aoqi@0:                 c3 = Integer.class;
aoqi@0:             else if(c3 == Float.TYPE)
aoqi@0:                 c3 = Float.class;
aoqi@0:             else if(c3 == Long.TYPE)
aoqi@0:                 c3 = Long.class;
aoqi@0:             else if(c3 == Double.TYPE)
aoqi@0:                 c3 = Double.class;
aoqi@0:         }
aoqi@0:         Set<Class<?>> a1 = getAssignables(c1, c3);
aoqi@0:         Set<Class<?>> a2 = getAssignables(c3, c1);
aoqi@0:         a1.retainAll(a2);
aoqi@0:         if(a1.isEmpty()) {
aoqi@0:             // Can happen when at least one of the arguments is an interface,
aoqi@0:             // as they don't have Object at the root of their hierarchy.
aoqi@0:             return Object.class;
aoqi@0:         }
aoqi@0:         // Gather maximally specific elements. Yes, there can be more than one
aoqi@0:         // thank to interfaces. I.e., if you call this method for String.class
aoqi@0:         // and Number.class, you'll have Comparable, Serializable, and Object
aoqi@0:         // as maximal elements.
aoqi@0:         List<Class<?>> max = new ArrayList<>();
aoqi@0:         outer: for(Class<?> clazz: a1) {
aoqi@0:             for(Iterator<Class<?>> maxiter = max.iterator(); maxiter.hasNext();) {
aoqi@0:                 Class<?> maxClazz = maxiter.next();
aoqi@0:                 if(isSubtype(maxClazz, clazz)) {
aoqi@0:                     // It can't be maximal, if there's already a more specific
aoqi@0:                     // maximal than it.
aoqi@0:                     continue outer;
aoqi@0:                 }
aoqi@0:                 if(isSubtype(clazz, maxClazz)) {
aoqi@0:                     // If it's more specific than a currently maximal element,
aoqi@0:                     // that currently maximal is no longer a maximal.
aoqi@0:                     maxiter.remove();
aoqi@0:                 }
aoqi@0:             }
aoqi@0:             // If we get here, no current maximal is more specific than the
aoqi@0:             // current class, so it is considered maximal as well
aoqi@0:             max.add(clazz);
aoqi@0:         }
aoqi@0:         if(max.size() > 1) {
aoqi@0:             return OBJECT_CLASS;
aoqi@0:         }
aoqi@0:         return max.get(0);
aoqi@0:     }
aoqi@0: 
aoqi@0:     private static Set<Class<?>> getAssignables(Class<?> c1, Class<?> c2) {
aoqi@0:         Set<Class<?>> s = new HashSet<>();
aoqi@0:         collectAssignables(c1, c2, s);
aoqi@0:         return s;
aoqi@0:     }
aoqi@0: 
aoqi@0:     private static void collectAssignables(Class<?> c1, Class<?> c2, Set<Class<?>> s) {
aoqi@0:         if(c1.isAssignableFrom(c2)) {
aoqi@0:             s.add(c1);
aoqi@0:         }
aoqi@0:         Class<?> sc = c1.getSuperclass();
aoqi@0:         if(sc != null) {
aoqi@0:             collectAssignables(sc, c2, s);
aoqi@0:         }
aoqi@0:         Class<?>[] itf = c1.getInterfaces();
aoqi@0:         for(int i = 0; i < itf.length; ++i) {
aoqi@0:             collectAssignables(itf[i], c2, s);
aoqi@0:         }
aoqi@0:     }
aoqi@0: 
aoqi@0:     private static final Map<Class<?>, Class<?>> WRAPPER_TYPES = createWrapperTypes();
aoqi@0:     private static final Map<Class<?>, Class<?>> PRIMITIVE_TYPES = invertMap(WRAPPER_TYPES);
aoqi@0:     private static final Map<String, Class<?>> PRIMITIVE_TYPES_BY_NAME = createClassNameMapping(WRAPPER_TYPES.keySet());
aoqi@0: 
aoqi@0:     private static Map<Class<?>, Class<?>> createWrapperTypes() {
aoqi@0:         final Map<Class<?>, Class<?>> wrapperTypes = new IdentityHashMap<>(8);
aoqi@0:         wrapperTypes.put(Boolean.TYPE, Boolean.class);
aoqi@0:         wrapperTypes.put(Byte.TYPE, Byte.class);
aoqi@0:         wrapperTypes.put(Character.TYPE, Character.class);
aoqi@0:         wrapperTypes.put(Short.TYPE, Short.class);
aoqi@0:         wrapperTypes.put(Integer.TYPE, Integer.class);
aoqi@0:         wrapperTypes.put(Long.TYPE, Long.class);
aoqi@0:         wrapperTypes.put(Float.TYPE, Float.class);
aoqi@0:         wrapperTypes.put(Double.TYPE, Double.class);
aoqi@0:         return Collections.unmodifiableMap(wrapperTypes);
aoqi@0:     }
aoqi@0: 
aoqi@0:     private static Map<String, Class<?>> createClassNameMapping(Collection<Class<?>> classes) {
aoqi@0:         final Map<String, Class<?>> map = new HashMap<>();
aoqi@0:         for(Class<?> clazz: classes) {
aoqi@0:             map.put(clazz.getName(), clazz);
aoqi@0:         }
aoqi@0:         return map;
aoqi@0:     }
aoqi@0: 
aoqi@0:     private static <K, V> Map<V, K> invertMap(Map<K, V> map) {
aoqi@0:         final Map<V, K> inverted = new IdentityHashMap<>(map.size());
aoqi@0:         for(Map.Entry<K, V> entry: map.entrySet()) {
aoqi@0:             inverted.put(entry.getValue(), entry.getKey());
aoqi@0:         }
aoqi@0:         return Collections.unmodifiableMap(inverted);
aoqi@0:     }
aoqi@0: 
aoqi@0:     /**
aoqi@0:      * Determines whether one type can be converted to another type using a method invocation conversion, as per JLS 5.3
aoqi@0:      * "Method Invocation Conversion". This is basically all conversions allowed by subtyping (see
aoqi@0:      * {@link #isSubtype(Class, Class)}) as well as boxing conversion (JLS 5.1.7) optionally followed by widening
aoqi@0:      * reference conversion and unboxing conversion (JLS 5.1.8) optionally followed by widening primitive conversion.
aoqi@0:      *
aoqi@0:      * @param callSiteType the parameter type at the call site
aoqi@0:      * @param methodType the parameter type in the method declaration
aoqi@0:      * @return true if callSiteType is method invocation convertible to the methodType.
aoqi@0:      */
aoqi@0:     public static boolean isMethodInvocationConvertible(Class<?> callSiteType, Class<?> methodType) {
aoqi@0:         if(methodType.isAssignableFrom(callSiteType)) {
aoqi@0:             return true;
aoqi@0:         }
aoqi@0:         if(callSiteType.isPrimitive()) {
aoqi@0:             if(methodType.isPrimitive()) {
aoqi@0:                 return isProperPrimitiveSubtype(callSiteType, methodType);
aoqi@0:             }
aoqi@0:             // Boxing + widening reference conversion
aoqi@0:             return methodType.isAssignableFrom(WRAPPER_TYPES.get(callSiteType));
aoqi@0:         }
aoqi@0:         if(methodType.isPrimitive()) {
aoqi@0:             final Class<?> unboxedCallSiteType = PRIMITIVE_TYPES.get(callSiteType);
aoqi@0:             return unboxedCallSiteType != null
aoqi@0:                     && (unboxedCallSiteType == methodType || isProperPrimitiveSubtype(unboxedCallSiteType, methodType));
aoqi@0:         }
aoqi@0:         return false;
aoqi@0:     }
aoqi@0: 
aoqi@0:     /**
aoqi@0:      * Determines whether one type can be potentially converted to another type at runtime. Allows a conversion between
aoqi@0:      * any subtype and supertype in either direction, and also allows a conversion between any two primitive types, as
aoqi@0:      * well as between any primitive type and any reference type that can hold a boxed primitive.
aoqi@0:      *
aoqi@0:      * @param callSiteType the parameter type at the call site
aoqi@0:      * @param methodType the parameter type in the method declaration
aoqi@0:      * @return true if callSiteType is potentially convertible to the methodType.
aoqi@0:      */
aoqi@0:     public static boolean isPotentiallyConvertible(Class<?> callSiteType, Class<?> methodType) {
aoqi@0:         // Widening or narrowing reference conversion
aoqi@0:         if(methodType.isAssignableFrom(callSiteType) || callSiteType.isAssignableFrom(methodType)) {
aoqi@0:             return true;
aoqi@0:         }
aoqi@0:         if(callSiteType.isPrimitive()) {
aoqi@0:             // Allow any conversion among primitives, as well as from any
aoqi@0:             // primitive to any type that can receive a boxed primitive.
aoqi@0:             // TODO: narrow this a bit, i.e. allow, say, boolean to Character?
aoqi@0:             // MethodHandles.convertArguments() allows it, so we might need to
aoqi@0:             // too.
aoqi@0:             return methodType.isPrimitive() || isAssignableFromBoxedPrimitive(methodType);
aoqi@0:         }
aoqi@0:         if(methodType.isPrimitive()) {
aoqi@0:             // Allow conversion from any reference type that can contain a
aoqi@0:             // boxed primitive to any primitive.
aoqi@0:             // TODO: narrow this a bit too?
aoqi@0:             return isAssignableFromBoxedPrimitive(callSiteType);
aoqi@0:         }
aoqi@0:         return false;
aoqi@0:     }
aoqi@0: 
aoqi@0:     /**
aoqi@0:      * Determines whether one type is a subtype of another type, as per JLS 4.10 "Subtyping". Note: this is not strict
aoqi@0:      * or proper subtype, therefore true is also returned for identical types; to be completely precise, it allows
aoqi@0:      * identity conversion (JLS 5.1.1), widening primitive conversion (JLS 5.1.2) and widening reference conversion (JLS
aoqi@0:      * 5.1.5).
aoqi@0:      *
aoqi@0:      * @param subType the supposed subtype
aoqi@0:      * @param superType the supposed supertype of the subtype
aoqi@0:      * @return true if subType can be converted by identity conversion, widening primitive conversion, or widening
aoqi@0:      * reference conversion to superType.
aoqi@0:      */
aoqi@0:     public static boolean isSubtype(Class<?> subType, Class<?> superType) {
aoqi@0:         // Covers both JLS 4.10.2 "Subtyping among Class and Interface Types"
aoqi@0:         // and JLS 4.10.3 "Subtyping among Array Types", as well as primitive
aoqi@0:         // type identity.
aoqi@0:         if(superType.isAssignableFrom(subType)) {
aoqi@0:             return true;
aoqi@0:         }
aoqi@0:         // JLS 4.10.1 "Subtyping among Primitive Types". Note we don't test for
aoqi@0:         // identity, as identical types were taken care of in the
aoqi@0:         // isAssignableFrom test. As per 4.10.1, the supertype relation is as
aoqi@0:         // follows:
aoqi@0:         // double > float
aoqi@0:         // float > long
aoqi@0:         // long > int
aoqi@0:         // int > short
aoqi@0:         // int > char
aoqi@0:         // short > byte
aoqi@0:         if(superType.isPrimitive() && subType.isPrimitive()) {
aoqi@0:             return isProperPrimitiveSubtype(subType, superType);
aoqi@0:         }
aoqi@0:         return false;
aoqi@0:     }
aoqi@0: 
aoqi@0:     /**
aoqi@0:      * Returns true if a supposed primitive subtype is a proper subtype ( meaning, subtype and not identical) of the
aoqi@0:      * supposed primitive supertype
aoqi@0:      *
aoqi@0:      * @param subType the supposed subtype
aoqi@0:      * @param superType the supposed supertype
aoqi@0:      * @return true if subType is a proper (not identical to) primitive subtype of the superType
aoqi@0:      */
aoqi@0:     private static boolean isProperPrimitiveSubtype(Class<?> subType, Class<?> superType) {
aoqi@0:         if(superType == boolean.class || subType == boolean.class) {
aoqi@0:             return false;
aoqi@0:         }
aoqi@0:         if(subType == byte.class) {
aoqi@0:             return superType != char.class;
aoqi@0:         }
aoqi@0:         if(subType == char.class) {
aoqi@0:             return superType != short.class && superType != byte.class;
aoqi@0:         }
aoqi@0:         if(subType == short.class) {
aoqi@0:             return superType != char.class && superType != byte.class;
aoqi@0:         }
aoqi@0:         if(subType == int.class) {
aoqi@0:             return superType == long.class || superType == float.class || superType == double.class;
aoqi@0:         }
aoqi@0:         if(subType == long.class) {
aoqi@0:             return superType == float.class || superType == double.class;
aoqi@0:         }
aoqi@0:         if(subType == float.class) {
aoqi@0:             return superType == double.class;
aoqi@0:         }
aoqi@0:         return false;
aoqi@0:     }
aoqi@0: 
aoqi@0:     private static final Map<Class<?>, Class<?>> WRAPPER_TO_PRIMITIVE_TYPES = createWrapperToPrimitiveTypes();
aoqi@0: 
aoqi@0:     private static Map<Class<?>, Class<?>> createWrapperToPrimitiveTypes() {
aoqi@0:         final Map<Class<?>, Class<?>> classes = new IdentityHashMap<>();
aoqi@0:         classes.put(Void.class, Void.TYPE);
aoqi@0:         classes.put(Boolean.class, Boolean.TYPE);
aoqi@0:         classes.put(Byte.class, Byte.TYPE);
aoqi@0:         classes.put(Character.class, Character.TYPE);
aoqi@0:         classes.put(Short.class, Short.TYPE);
aoqi@0:         classes.put(Integer.class, Integer.TYPE);
aoqi@0:         classes.put(Long.class, Long.TYPE);
aoqi@0:         classes.put(Float.class, Float.TYPE);
aoqi@0:         classes.put(Double.class, Double.TYPE);
aoqi@0:         return classes;
aoqi@0:     }
aoqi@0: 
aoqi@0:     private static final Set<Class<?>> PRIMITIVE_WRAPPER_TYPES = createPrimitiveWrapperTypes();
aoqi@0: 
aoqi@0:     private static Set<Class<?>> createPrimitiveWrapperTypes() {
aoqi@0:         final Map<Class<?>, Class<?>> classes = new IdentityHashMap<>();
aoqi@0:         addClassHierarchy(classes, Boolean.class);
aoqi@0:         addClassHierarchy(classes, Byte.class);
aoqi@0:         addClassHierarchy(classes, Character.class);
aoqi@0:         addClassHierarchy(classes, Short.class);
aoqi@0:         addClassHierarchy(classes, Integer.class);
aoqi@0:         addClassHierarchy(classes, Long.class);
aoqi@0:         addClassHierarchy(classes, Float.class);
aoqi@0:         addClassHierarchy(classes, Double.class);
aoqi@0:         return classes.keySet();
aoqi@0:     }
aoqi@0: 
aoqi@0:     private static void addClassHierarchy(Map<Class<?>, Class<?>> map, Class<?> clazz) {
aoqi@0:         if(clazz == null) {
aoqi@0:             return;
aoqi@0:         }
aoqi@0:         map.put(clazz, clazz);
aoqi@0:         addClassHierarchy(map, clazz.getSuperclass());
aoqi@0:         for(Class<?> itf: clazz.getInterfaces()) {
aoqi@0:             addClassHierarchy(map, itf);
aoqi@0:         }
aoqi@0:     }
aoqi@0: 
aoqi@0:     /**
aoqi@0:      * Returns true if the class can be assigned from any boxed primitive.
aoqi@0:      *
aoqi@0:      * @param clazz the class
aoqi@0:      * @return true if the class can be assigned from any boxed primitive. Basically, it is true if the class is any
aoqi@0:      * primitive wrapper class, or a superclass or superinterface of any primitive wrapper class.
aoqi@0:      */
aoqi@0:     private static boolean isAssignableFromBoxedPrimitive(Class<?> clazz) {
aoqi@0:         return PRIMITIVE_WRAPPER_TYPES.contains(clazz);
aoqi@0:     }
aoqi@0: 
aoqi@0:     /**
aoqi@0:      * Given a name of a primitive type (except "void"), returns the class representing it. I.e. when invoked with
aoqi@0:      * "int", returns {@link Integer#TYPE}.
aoqi@0:      * @param name the name of the primitive type
aoqi@0:      * @return the class representing the primitive type, or null if the name does not correspond to a primitive type
aoqi@0:      * or is "void".
aoqi@0:      */
aoqi@0:     public static Class<?> getPrimitiveTypeByName(String name) {
aoqi@0:         return PRIMITIVE_TYPES_BY_NAME.get(name);
aoqi@0:     }
aoqi@0: 
aoqi@0:     /**
aoqi@0:      * When passed a class representing a wrapper for a primitive type, returns the class representing the corresponding
aoqi@0:      * primitive type. I.e. calling it with {@code Integer.class} will return {@code Integer.TYPE}. If passed a class
aoqi@0:      * that is not a wrapper for primitive type, returns null.
aoqi@0:      * @param wrapperType the class object representing a wrapper for a primitive type
aoqi@0:      * @return the class object representing the primitive type, or null if the passed class is not a primitive wrapper.
aoqi@0:      */
aoqi@0:     public static Class<?> getPrimitiveType(Class<?> wrapperType) {
aoqi@0:         return WRAPPER_TO_PRIMITIVE_TYPES.get(wrapperType);
aoqi@0:     }
aoqi@0: 
aoqi@0: 
aoqi@0:     /**
aoqi@0:      * When passed a class representing a primitive type, returns the class representing the corresponding
aoqi@0:      * wrapper type. I.e. calling it with {@code int.class} will return {@code Integer.class}. If passed a class
aoqi@0:      * that is not a primitive type, returns null.
aoqi@0:      * @param primitiveType the class object representing a primitive type
aoqi@0:      * @return the class object representing the wrapper type, or null if the passed class is not a primitive.
aoqi@0:      */
aoqi@0:     public static Class<?> getWrapperType(Class<?> primitiveType) {
aoqi@0:         return WRAPPER_TYPES.get(primitiveType);
aoqi@0:     }
aoqi@0: }