/* * Copyright 2002-2018 the original author or authors. * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ package org.springframework.web.servlet.handler; import java.util.Collections; import java.util.List; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; import org.springframework.core.Ordered; import org.springframework.lang.Nullable; import org.springframework.web.servlet.HandlerExceptionResolver; import org.springframework.web.servlet.ModelAndView; /** * A {@link HandlerExceptionResolver} that delegates to a list of other * {@link HandlerExceptionResolver HandlerExceptionResolvers}. * * @author Rossen Stoyanchev * @since 3.1 */ public class HandlerExceptionResolverComposite implements HandlerExceptionResolver, Ordered { @Nullable private List<HandlerExceptionResolver> resolvers; private int order = Ordered.LOWEST_PRECEDENCE; /** * Set the list of exception resolvers to delegate to. */ public void setExceptionResolvers(List<HandlerExceptionResolver> exceptionResolvers) { this.resolvers = exceptionResolvers; } /** * Return the list of exception resolvers to delegate to. */ public List<HandlerExceptionResolver> getExceptionResolvers() { return (this.resolvers != null ? Collections.unmodifiableList(this.resolvers) : Collections.emptyList()); } public void setOrder(int order) { this.order = order; } @Override public int getOrder() { return this.order; } /** * Resolve the exception by iterating over the list of configured exception resolvers. * <p>The first one to return a {@link ModelAndView} wins. Otherwise {@code null} * is returned. */ @Override @Nullable public ModelAndView resolveException(HttpServletRequest request, HttpServletResponse response, @Nullable Object handler,Exception ex) { if (this.resolvers != null) { for (HandlerExceptionResolver handlerExceptionResolver : this.resolvers) { ModelAndView mav = handlerExceptionResolver.resolveException(request, response, handler, ex); if (mav != null) { return mav; } } } return null; } }