001/* 002 * Copyright 2002-2017 the original author or authors. 003 * 004 * Licensed under the Apache License, Version 2.0 (the "License"); 005 * you may not use this file except in compliance with the License. 006 * You may obtain a copy of the License at 007 * 008 * https://www.apache.org/licenses/LICENSE-2.0 009 * 010 * Unless required by applicable law or agreed to in writing, software 011 * distributed under the License is distributed on an "AS IS" BASIS, 012 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 013 * See the License for the specific language governing permissions and 014 * limitations under the License. 015 */ 016 017package org.springframework.context.expression; 018 019import java.lang.reflect.AnnotatedElement; 020 021import org.springframework.util.Assert; 022import org.springframework.util.ObjectUtils; 023 024/** 025 * Represent an {@link AnnotatedElement} on a particular {@link Class} 026 * and is suitable as a key. 027 * 028 * @author Costin Leau 029 * @author Stephane Nicoll 030 * @since 4.2 031 * @see CachedExpressionEvaluator 032 */ 033public final class AnnotatedElementKey implements Comparable<AnnotatedElementKey> { 034 035 private final AnnotatedElement element; 036 037 private final Class<?> targetClass; 038 039 040 /** 041 * Create a new instance with the specified {@link AnnotatedElement} and 042 * optional target {@link Class}. 043 */ 044 public AnnotatedElementKey(AnnotatedElement element, Class<?> targetClass) { 045 Assert.notNull(element, "AnnotatedElement must not be null"); 046 this.element = element; 047 this.targetClass = targetClass; 048 } 049 050 051 @Override 052 public boolean equals(Object other) { 053 if (this == other) { 054 return true; 055 } 056 if (!(other instanceof AnnotatedElementKey)) { 057 return false; 058 } 059 AnnotatedElementKey otherKey = (AnnotatedElementKey) other; 060 return (this.element.equals(otherKey.element) && 061 ObjectUtils.nullSafeEquals(this.targetClass, otherKey.targetClass)); 062 } 063 064 @Override 065 public int hashCode() { 066 return this.element.hashCode() + (this.targetClass != null ? this.targetClass.hashCode() * 29 : 0); 067 } 068 069 @Override 070 public String toString() { 071 return this.element + (this.targetClass != null ? " on " + this.targetClass : ""); 072 } 073 074 @Override 075 public int compareTo(AnnotatedElementKey other) { 076 int result = this.element.toString().compareTo(other.element.toString()); 077 if (result == 0 && this.targetClass != null) { 078 if (other.targetClass == null) { 079 return 1; 080 } 081 result = this.targetClass.getName().compareTo(other.targetClass.getName()); 082 } 083 return result; 084 } 085 086}