1 /*
2 * Copyright 2002-2014 the original author or authors.
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 * http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17 package org.springframework.web.servlet.mvc.method.annotation;
18
19 import org.springframework.core.MethodParameter;
20 import org.springframework.util.PatternMatchUtils;
21 import org.springframework.web.context.request.NativeWebRequest;
22 import org.springframework.web.method.support.HandlerMethodReturnValueHandler;
23 import org.springframework.web.method.support.ModelAndViewContainer;
24 import org.springframework.web.servlet.ModelAndView;
25 import org.springframework.web.servlet.SmartView;
26 import org.springframework.web.servlet.View;
27
28 /**
29 * Handles return values of type {@link ModelAndView} copying view and model
30 * information to the {@link ModelAndViewContainer}.
31 *
32 * <p>If the return value is {@code null}, the
33 * {@link ModelAndViewContainer#setRequestHandled(boolean)} flag is set to
34 * {@code true} to indicate the request was handled directly.
35 *
36 * <p>A {@link ModelAndView} return type has a set purpose. Therefore this
37 * handler should be configured ahead of handlers that support any return
38 * value type annotated with {@code @ModelAttribute} or {@code @ResponseBody}
39 * to ensure they don't take over.
40 *
41 * @author Rossen Stoyanchev
42 * @since 3.1
43 */
44 public class ModelAndViewMethodReturnValueHandler implements HandlerMethodReturnValueHandler {
45
46 private String[] redirectPatterns;
47
48
49 /**
50 * Configure one more simple patterns (as described in
51 * {@link org.springframework.util.PatternMatchUtils#simpleMatch}) to use in order to recognize
52 * custom redirect prefixes in addition to "redirect:".
53 * <p>Note that simply configuring this property will not make a custom
54 * redirect prefix work. There must be a custom View that recognizes the
55 * prefix as well.
56 * @since 4.1
57 */
58 public void setRedirectPatterns(String... redirectPatterns) {
59 this.redirectPatterns = redirectPatterns;
60 }
61
62 /**
63 * The configured redirect patterns, if any.
64 */
65 public String[] getRedirectPatterns() {
66 return this.redirectPatterns;
67 }
68
69
70 @Override
71 public boolean supportsReturnType(MethodParameter returnType) {
72 return ModelAndView.class.isAssignableFrom(returnType.getParameterType());
73 }
74
75 @Override
76 public void handleReturnValue(Object returnValue, MethodParameter returnType,
77 ModelAndViewContainer mavContainer, NativeWebRequest webRequest) throws Exception {
78
79 if (returnValue == null) {
80 mavContainer.setRequestHandled(true);
81 return;
82 }
83
84 ModelAndView mav = (ModelAndView) returnValue;
85 if (mav.isReference()) {
86 String viewName = mav.getViewName();
87 mavContainer.setViewName(viewName);
88 if (viewName != null && isRedirectViewName(viewName)) {
89 mavContainer.setRedirectModelScenario(true);
90 }
91 }
92 else {
93 View view = mav.getView();
94 mavContainer.setView(view);
95 if (view instanceof SmartView) {
96 if (((SmartView) view).isRedirectView()) {
97 mavContainer.setRedirectModelScenario(true);
98 }
99 }
100 }
101 mavContainer.addAllAttributes(mav.getModel());
102 }
103
104 /**
105 * Whether the given view name is a redirect view reference.
106 * The default implementation checks the configured redirect patterns and
107 * also if the view name starts with the "redirect:" prefix.
108 * @param viewName the view name to check, never {@code null}
109 * @return "true" if the given view name is recognized as a redirect view
110 * reference; "false" otherwise.
111 */
112 protected boolean isRedirectViewName(String viewName) {
113 if (PatternMatchUtils.simpleMatch(this.redirectPatterns, viewName)) {
114 return true;
115 }
116 return viewName.startsWith("redirect:");
117 }
118
119 }