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1 package com.opensymphony.webwork.interceptor;
2
3 import com.opensymphony.webwork.ServletActionContext;
4 import com.opensymphony.xwork.ActionContext;
5 import com.opensymphony.xwork.ActionInvocation;
6 import com.opensymphony.xwork.ActionProxy;
7 import com.opensymphony.xwork.interceptor.AroundInterceptor;
8 import com.opensymphony.xwork.interceptor.PreResultListener;
9 import com.opensymphony.xwork.util.OgnlValueStack;
10 import org.apache.commons.logging.Log;
11 import org.apache.commons.logging.LogFactory;
12
13 import javax.servlet.ServletContext  ;
14 import javax.servlet.http.HttpServletRequest ;
15 import javax.servlet.http.HttpSession ;
16 import java.util.IdentityHashMap ;
17 import java.util.Map ;
18
19
22 public class ScopeInterceptor extends AroundInterceptor implements PreResultListener {
23 private static final Log LOG = LogFactory.getLog(ScopeInterceptor.class);
24
25 private static Map locks = new IdentityHashMap ();
26
27 String [] application = null;
28 String [] session = null;
29 String key;
30 String type = null;
31
32 public void setApplication(String s) {
34 if (s != null) {
35 application = s.split(" *, *");
36 }
37 }
38
39 public void setSession(String s) {
41 if (s != null) {
42 session = s.split(" *, *");
43 }
44 }
45
46 private String getKey(ActionInvocation invocation) {
47 ActionProxy proxy = invocation.getProxy();
48 if (key == null || "CLASS".equals(key)) {
49 key = "webwork.ScopeInterceptor:" + proxy.getNamespace() + ":" + proxy.getAction().getClass();
51 } else if ("ACTION".equals(key)) {
52 key = "webwork.ScopeInterceptor:" + proxy.getNamespace() + ":" + proxy.getActionName();
53 }
54 return key;
55 }
56
57 public ScopeInterceptor() {
58 super();
59 }
60
61
62 private static final Object NULL = new Object () {
63 public String toString() {
64 return "NULL";
65 }
66 };
67
68 private static Object nullConvert(Object o) {
69 if (o == null) {
70 return NULL;
71 }
72
73 if (o == NULL) {
74 return null;
75 }
76
77 return o;
78 }
79
80 static void lock(Object o, ActionInvocation invocation) throws Exception {
81 synchronized (o) {
82 int count = 3;
83 Object previous;
84 while ((previous = locks.get(o)) != null) {
85 if (previous == invocation) {
86 return;
87 }
88
89 if (count-- <= 0) {
90 throw new RuntimeException ("Deadlock in session lock");
91 }
92 o.wait(60000);
93 }
94 locks.put(o, invocation);
95 }
96 }
97
98 static void unlock(Object o) {
99 synchronized (o) {
100 locks.remove(o);
101 o.notify();
102 }
103 }
104
105 protected void after(ActionInvocation dispatcher, String result) throws Exception {
106 }
107
108 protected void before(ActionInvocation invocation) throws Exception {
109 invocation.addPreResultListener(this);
110
111 ActionContext ctx = invocation.getInvocationContext();
112 HttpServletRequest req = (HttpServletRequest ) ctx.get(ServletActionContext.HTTP_REQUEST);
113 ServletContext app = (ServletContext ) ctx.get(ServletActionContext.SERVLET_CONTEXT);
114 OgnlValueStack stack = invocation.getStack();
115 HttpSession ses = req.getSession(true);
116
117 lock(ses, invocation);
119 String key = getKey(invocation);
120
121 if (application != null) {
122 for (int i = 0; i < application.length; i++) {
123 String string = application[i];
124 Object attribute = app.getAttribute(key + string);
125 if (attribute != null) {
126 if (LOG.isDebugEnabled()) {
127 log.debug("application scoped variable set " + string + " = " + String.valueOf(attribute));
128 }
129
130 stack.setValue(string, nullConvert(attribute));
131 }
132 }
133 }
134
135 if (session != null && (!"start".equals(type))) {
136 for (int i = 0; i < session.length; i++) {
137 String string = session[i];
138 Object attribute = ses.getAttribute(key + string);
139 if (attribute != null) {
140 if (LOG.isDebugEnabled()) {
141 log.debug("application scoped variable set " + string + " = " + String.valueOf(attribute));
142 }
143
144 stack.setValue(string, nullConvert(attribute));
145 }
146 }
147 }
148 }
149
150
153 public void setKey(String key) {
154 this.key = key;
155 }
156
157 public void beforeResult(ActionInvocation invocation, String resultCode) {
158 HttpSession ses = ServletActionContext.getRequest().getSession();
159 try {
160 String key = getKey(invocation);
161 ServletContext app = ServletActionContext.getServletContext();
162 final OgnlValueStack stack = ActionContext.getContext().getValueStack();
163
164 if (application != null)
165 for (int i = 0; i < application.length; i++) {
166 String string = application[i];
167 Object value = stack.findValue(string);
168 if (LOG.isDebugEnabled()) {
169 log.debug("application scoped variable saved " + string + " = " + String.valueOf(value));
170 }
171
172 app.setAttribute(key + string, nullConvert(value));
174 }
175
176 boolean ends = "end".equals(type);
177
178 if (session != null)
179 for (int i = 0; i < session.length; i++) {
180 String string = session[i];
181 if (ends) {
182 ses.removeAttribute(key + string);
183 } else {
184 Object value = stack.findValue(string);
185
186 if (LOG.isDebugEnabled()) {
187 log.debug("session scoped variable saved " + string + " = " + String.valueOf(value));
188 }
189
190 ses.setAttribute(key + string, nullConvert(value));
193 }
194 }
195
196
197 } finally {
198 unlock(ses);
199 }
200 }
201
202
205 public String getType() {
206 return type;
207 }
208
209
212 public void setType(String type) {
213 type = type.toLowerCase();
214 if ("start".equals(type) || "end".equals(type)) {
215 this.type = type;
216 } else {
217 throw new IllegalArgumentException ("Only start or end are allowed arguments for type");
218 }
219 }
220 } |
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