001/* 002 * Copyright 2002-2018 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.aop.aspectj; 018 019import java.lang.reflect.InvocationTargetException; 020 021import org.springframework.aop.framework.AopConfigException; 022import org.springframework.core.Ordered; 023import org.springframework.lang.Nullable; 024import org.springframework.util.Assert; 025import org.springframework.util.ReflectionUtils; 026 027/** 028 * Implementation of {@link AspectInstanceFactory} that creates a new instance 029 * of the specified aspect class for every {@link #getAspectInstance()} call. 030 * 031 * @author Juergen Hoeller 032 * @since 2.0.4 033 */ 034public class SimpleAspectInstanceFactory implements AspectInstanceFactory { 035 036 private final Class<?> aspectClass; 037 038 039 /** 040 * Create a new SimpleAspectInstanceFactory for the given aspect class. 041 * @param aspectClass the aspect class 042 */ 043 public SimpleAspectInstanceFactory(Class<?> aspectClass) { 044 Assert.notNull(aspectClass, "Aspect class must not be null"); 045 this.aspectClass = aspectClass; 046 } 047 048 049 /** 050 * Return the specified aspect class (never {@code null}). 051 */ 052 public final Class<?> getAspectClass() { 053 return this.aspectClass; 054 } 055 056 @Override 057 public final Object getAspectInstance() { 058 try { 059 return ReflectionUtils.accessibleConstructor(this.aspectClass).newInstance(); 060 } 061 catch (NoSuchMethodException ex) { 062 throw new AopConfigException( 063 "No default constructor on aspect class: " + this.aspectClass.getName(), ex); 064 } 065 catch (InstantiationException ex) { 066 throw new AopConfigException( 067 "Unable to instantiate aspect class: " + this.aspectClass.getName(), ex); 068 } 069 catch (IllegalAccessException ex) { 070 throw new AopConfigException( 071 "Could not access aspect constructor: " + this.aspectClass.getName(), ex); 072 } 073 catch (InvocationTargetException ex) { 074 throw new AopConfigException( 075 "Failed to invoke aspect constructor: " + this.aspectClass.getName(), ex.getTargetException()); 076 } 077 } 078 079 @Override 080 @Nullable 081 public ClassLoader getAspectClassLoader() { 082 return this.aspectClass.getClassLoader(); 083 } 084 085 /** 086 * Determine the order for this factory's aspect instance, 087 * either an instance-specific order expressed through implementing 088 * the {@link org.springframework.core.Ordered} interface, 089 * or a fallback order. 090 * @see org.springframework.core.Ordered 091 * @see #getOrderForAspectClass 092 */ 093 @Override 094 public int getOrder() { 095 return getOrderForAspectClass(this.aspectClass); 096 } 097 098 /** 099 * Determine a fallback order for the case that the aspect instance 100 * does not express an instance-specific order through implementing 101 * the {@link org.springframework.core.Ordered} interface. 102 * <p>The default implementation simply returns {@code Ordered.LOWEST_PRECEDENCE}. 103 * @param aspectClass the aspect class 104 */ 105 protected int getOrderForAspectClass(Class<?> aspectClass) { 106 return Ordered.LOWEST_PRECEDENCE; 107 } 108 109}