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1 /*
2 * Copyright (c) 2002-2007 by OpenSymphony
3 * All rights reserved.
4 */
5 package com.opensymphony.xwork2.interceptor;
6
7 import java.util.ArrayList;
8 import java.util.Collection;
9 import java.util.Collections;
10 import java.util.Iterator;
11 import java.util.List;
12 import java.util.Map;
13
14 import com.opensymphony.xwork2.ActionInvocation;
15 import com.opensymphony.xwork2.Unchainable;
16 import com.opensymphony.xwork2.inject.Inject;
17 import com.opensymphony.xwork2.util.CompoundRoot;
18 import com.opensymphony.xwork2.util.ValueStack;
19 import com.opensymphony.xwork2.util.logging.Logger;
20 import com.opensymphony.xwork2.util.logging.LoggerFactory;
21 import com.opensymphony.xwork2.util.reflection.ReflectionProvider;
22
23
24 /**
25 * <!-- START SNIPPET: description -->
26 *
27 * An interceptor that copies all the properties of every object in the value stack to the currently executing object,
28 * except for any object that implements {@link Unchainable}. A collection of optional <i>includes</i> and
29 * <i>excludes</i> may be provided to control how and which parameters are copied. Only includes or excludes may be
30 * specified. Specifying both results in undefined behavior. See the javadocs for {@link ReflectionProvider#copy(Object, Object,
31 * java.util.Map, java.util.Collection, java.util.Collection)} for more information.
32 *
33 * <p/>
34 * <b>Note:</b> It is important to remember that this interceptor does nothing if there are no objects already on the stack.
35 * <br/>This means two things:
36 * <br/><b>One</b>, you can safely apply it to all your actions without any worry of adverse affects.
37 * <br/><b/>Two</b>, it is up to you to ensure an object exists in the stack prior to invoking this action. The most typical way this is done
38 * is through the use of the <b>chain</b> result type, which combines with this interceptor to make up the action
39 * chaining feature.
40 *
41 * <!-- END SNIPPET: description -->
42 *
43 * <p/> <u>Interceptor parameters:</u>
44 *
45 * <!-- START SNIPPET: parameters -->
46 *
47 * <ul>
48 *
49 * <li>excludes (optional) - the list of parameter names to exclude from copying (all others will be included).</li>
50 *
51 * <li>includes (optional) - the list of parameter names to include when copying (all others will be excluded).</li>
52 *
53 * </ul>
54 *
55 * <!-- END SNIPPET: parameters -->
56 *
57 * <p/> <u>Extending the interceptor:</u>
58 *
59 * <p/>
60 *
61 * <!-- START SNIPPET: extending -->
62 *
63 * There are no known extension points to this interceptor.
64 *
65 * <!-- END SNIPPET: extending -->
66 *
67 * <p/> <u>Example code:</u>
68 *
69 * <pre>
70 * <!-- START SNIPPET: example -->
71 *
72 * <action name="someAction" class="com.examples.SomeAction">
73 * <interceptor-ref name="basicStack"/>
74 * <result name="success" type="chain">otherAction</result>
75 * </action>
76 *
77 * <action name="otherAction" class="com.examples.OtherAction">
78 * <interceptor-ref name="chain"/>
79 * <interceptor-ref name="basicStack"/>
80 * <result name="success">good_result.ftl</result>
81 * </action>
82 *
83 * <!-- END SNIPPET: example -->
84 * </pre>
85 *
86 * @see com.opensymphony.xwork2.ActionChainResult
87 * @author mrdon
88 * @author tm_jee ( tm_jee(at)yahoo.co.uk )
89 */
90 public class ChainingInterceptor extends AbstractInterceptor {
91
92 private static final Logger LOG = LoggerFactory.getLogger(ChainingInterceptor.class);
93
94 protected Collection excludes;
95 protected Collection includes;
96
97 protected ReflectionProvider reflectionProvider;
98
99 @Inject
100 public void setReflectionProvider(ReflectionProvider prov) {
101 this.reflectionProvider = prov;
102 }
103
104 public String intercept(ActionInvocation invocation) throws Exception {
105 ValueStack stack = invocation.getStack();
106 CompoundRoot root = stack.getRoot();
107
108 if (root.size() > 1) {
109 List list = new ArrayList(root);
110 list.remove(0);
111 Collections.reverse(list);
112
113 Map ctxMap = invocation.getInvocationContext().getContextMap();
114 Iterator iterator = list.iterator();
115 int index = 1; // starts with 1, 0 has been removed
116 while (iterator.hasNext()) {
117 index = index + 1;
118 Object o = iterator.next();
119 if (o != null) {
120 if (!(o instanceof Unchainable)) {
121 reflectionProvider.copy(o, invocation.getAction(), ctxMap, excludes, includes);
122 }
123 }
124 else {
125 LOG.warn("compound root element at index "+index+" is null");
126 }
127 }
128 }
129
130 return invocation.invoke();
131 }
132
133 /**
134 * Gets list of parameter names to exclude
135 *
136 * @return the exclude list
137 */
138 public Collection getExcludes() {
139 return excludes;
140 }
141
142 /**
143 * Sets the list of parameter names to exclude from copying (all others will be included).
144 *
145 * @param excludes the excludes list
146 */
147 public void setExcludes(Collection excludes) {
148 this.excludes = excludes;
149 }
150
151 /**
152 * Gets list of parameter names to include
153 *
154 * @return the include list
155 */
156 public Collection getIncludes() {
157 return includes;
158 }
159
160 /**
161 * Sets the list of parameter names to include when copying (all others will be excluded).
162 *
163 * @param includes the includes list
164 */
165 public void setIncludes(Collection includes) {
166 this.includes = includes;
167 }
168
169 }