001/* 002 * Copyright 2012-2017 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 * http://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.boot.web.server; 018 019import java.util.ArrayList; 020import java.util.Collection; 021import java.util.Collections; 022import java.util.List; 023 024import org.springframework.beans.BeansException; 025import org.springframework.beans.factory.BeanFactory; 026import org.springframework.beans.factory.BeanFactoryAware; 027import org.springframework.beans.factory.ListableBeanFactory; 028import org.springframework.beans.factory.config.BeanPostProcessor; 029import org.springframework.core.annotation.AnnotationAwareOrderComparator; 030import org.springframework.util.Assert; 031 032/** 033 * {@link BeanPostProcessor} that applies all {@link ErrorPageRegistrar}s from the bean 034 * factory to {@link ErrorPageRegistry} beans. 035 * 036 * @author Phillip Webb 037 * @author Stephane Nicoll 038 * @since 2.0.0 039 */ 040public class ErrorPageRegistrarBeanPostProcessor 041 implements BeanPostProcessor, BeanFactoryAware { 042 043 private ListableBeanFactory beanFactory; 044 045 private List<ErrorPageRegistrar> registrars; 046 047 @Override 048 public void setBeanFactory(BeanFactory beanFactory) { 049 Assert.isInstanceOf(ListableBeanFactory.class, beanFactory, 050 "ErrorPageRegistrarBeanPostProcessor can only be used " 051 + "with a ListableBeanFactory"); 052 this.beanFactory = (ListableBeanFactory) beanFactory; 053 } 054 055 @Override 056 public Object postProcessBeforeInitialization(Object bean, String beanName) 057 throws BeansException { 058 if (bean instanceof ErrorPageRegistry) { 059 postProcessBeforeInitialization((ErrorPageRegistry) bean); 060 } 061 return bean; 062 } 063 064 @Override 065 public Object postProcessAfterInitialization(Object bean, String beanName) 066 throws BeansException { 067 return bean; 068 } 069 070 private void postProcessBeforeInitialization(ErrorPageRegistry registry) { 071 for (ErrorPageRegistrar registrar : getRegistrars()) { 072 registrar.registerErrorPages(registry); 073 } 074 } 075 076 private Collection<ErrorPageRegistrar> getRegistrars() { 077 if (this.registrars == null) { 078 // Look up does not include the parent context 079 this.registrars = new ArrayList<>(this.beanFactory 080 .getBeansOfType(ErrorPageRegistrar.class, false, false).values()); 081 this.registrars.sort(AnnotationAwareOrderComparator.INSTANCE); 082 this.registrars = Collections.unmodifiableList(this.registrars); 083 } 084 return this.registrars; 085 } 086 087}