001/* 002 * Copyright 2002-2020 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.beans.factory.support; 018 019import org.springframework.beans.factory.config.BeanDefinitionHolder; 020import org.springframework.beans.factory.config.DependencyDescriptor; 021import org.springframework.lang.Nullable; 022 023/** 024 * {@link AutowireCandidateResolver} implementation to use when no annotation 025 * support is available. This implementation checks the bean definition only. 026 * 027 * @author Mark Fisher 028 * @author Juergen Hoeller 029 * @since 2.5 030 */ 031public class SimpleAutowireCandidateResolver implements AutowireCandidateResolver { 032 033 /** 034 * Shared instance of {@code SimpleAutowireCandidateResolver}. 035 * @since 5.2.7 036 */ 037 public static final SimpleAutowireCandidateResolver INSTANCE = new SimpleAutowireCandidateResolver(); 038 039 040 @Override 041 public boolean isAutowireCandidate(BeanDefinitionHolder bdHolder, DependencyDescriptor descriptor) { 042 return bdHolder.getBeanDefinition().isAutowireCandidate(); 043 } 044 045 @Override 046 public boolean isRequired(DependencyDescriptor descriptor) { 047 return descriptor.isRequired(); 048 } 049 050 @Override 051 public boolean hasQualifier(DependencyDescriptor descriptor) { 052 return false; 053 } 054 055 @Override 056 @Nullable 057 public Object getSuggestedValue(DependencyDescriptor descriptor) { 058 return null; 059 } 060 061 @Override 062 @Nullable 063 public Object getLazyResolutionProxyIfNecessary(DependencyDescriptor descriptor, @Nullable String beanName) { 064 return null; 065 } 066 067 /** 068 * This implementation returns {@code this} as-is. 069 * @see #INSTANCE 070 */ 071 @Override 072 public AutowireCandidateResolver cloneIfNecessary() { 073 return this; 074 } 075 076}