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1 package org.directwebremoting.webwork;
2
3 import java.io.UnsupportedEncodingException  ;
4 import java.util.Map ;
5
6 import javax.servlet.ServletContext ;
7 import javax.servlet.ServletException ;
8 import javax.servlet.http.HttpServletRequest ;
9 import javax.servlet.http.HttpServletResponse ;
10
11 import org.directwebremoting.util.FakeHttpServletResponse;
12 import org.directwebremoting.util.LocalUtil;
13 import org.directwebremoting.util.Logger;
14
15 import com.opensymphony.webwork.ServletActionContext;
16 import com.opensymphony.webwork.dispatcher.DispatcherUtils;
17 import com.opensymphony.webwork.dispatcher.mapper.ActionMapping;
18 import com.opensymphony.xwork.ActionContext;
19 import com.opensymphony.xwork.ActionInvocation;
20 import com.opensymphony.xwork.ActionProxy;
21 import com.opensymphony.xwork.ActionProxyFactory;
22 import com.opensymphony.xwork.Result;
23 import com.opensymphony.xwork.config.ConfigurationException;
24 import com.opensymphony.xwork.util.OgnlValueStack;
25 import com.opensymphony.xwork.util.XWorkContinuationConfig;
26
27
36 public class DWRAction
37 {
38
41 private static final Logger log = Logger.getLogger(DWRAction.class);
42
43 private static final String DWRACTIONPROCESSOR_INIT_PARAM = "dwrActionProcessor";
44
45 private static DWRAction s_instance;
46
47 private DispatcherUtils m_wwDispatcher;
48
49 private IDWRActionProcessor m_actionProcessor;
50
51 private DWRAction(ServletContext servletContext) throws ServletException
52 {
53 DispatcherUtils.initialize(servletContext);
54 m_wwDispatcher = DispatcherUtils.getInstance();
55 m_actionProcessor = loadActionProcessor(servletContext.getInitParameter(DWRACTIONPROCESSOR_INIT_PARAM));
56 }
57
58
70 public static AjaxResult execute(ActionDefinition actionDefinition, Map params, HttpServletRequest request, HttpServletResponse response, ServletContext servletContext) throws ServletException
71 {
72 initialize(servletContext);
73
74 return s_instance.doExecute(actionDefinition, params, request, response, servletContext);
75 }
76
77 protected AjaxResult doExecute(ActionDefinition actionDefinition, Map params, HttpServletRequest request, HttpServletResponse response, ServletContext servletContext) throws ServletException
78 {
79
80 FakeHttpServletResponse actionResponse = new FakeHttpServletResponse();
81
82 if (null != m_actionProcessor)
83 {
84 m_actionProcessor.preProcess(request, response, actionResponse, params);
85 }
86
87 m_wwDispatcher.prepare(request, actionResponse);
88
89 ActionInvocation invocation = invokeAction(m_wwDispatcher, request, actionResponse, servletContext, actionDefinition, params);
90
91 AjaxResult result = null;
92 if (actionDefinition.isExecuteResult())
93 {
94 result = getTextResult(actionResponse);
96 }
97 else
98 {
99 result = new DefaultAjaxDataResult(invocation.getAction());
100 }
101
102 if (null != m_actionProcessor)
103 {
104 m_actionProcessor.postProcess(request, response, actionResponse, result);
105 }
106
107 return result;
108 }
109
110 protected ActionInvocation invokeAction(DispatcherUtils du, HttpServletRequest request, HttpServletResponse response, ServletContext context, ActionDefinition actionDefinition, Map params) throws ServletException
111 {
112 ActionMapping mapping = getActionMapping(actionDefinition, params);
113 Map extraContext = du.createContextMap(request, response, mapping, context);
114
115 OgnlValueStack stack = (OgnlValueStack) request.getAttribute(ServletActionContext.WEBWORK_VALUESTACK_KEY);
117 if (null != stack)
118 {
119 extraContext.put(ActionContext.VALUE_STACK, new OgnlValueStack(stack));
120 }
121
122 try
123 {
124 prepareContinuationAction(request, extraContext);
125
126 ActionProxy proxy = ActionProxyFactory.getFactory().createActionProxy(actionDefinition.getNamespace(), actionDefinition.getAction(), extraContext, actionDefinition.isExecuteResult(), false);
127 proxy.setMethod(actionDefinition.getMethod());
128 request.setAttribute(ServletActionContext.WEBWORK_VALUESTACK_KEY, proxy.getInvocation().getStack());
129
130 if (mapping.getResult() != null)
132 {
133 Result result = mapping.getResult();
134 result.execute(proxy.getInvocation());
135 }
136 else
137 {
138 proxy.execute();
139 }
140
141 return proxy.getInvocation();
142 }
143 catch (ConfigurationException ce)
144 {
145 throw new ServletException ("Cannot invoke action '" + actionDefinition.getAction() + "' in namespace '" + actionDefinition.getNamespace() + "'", ce);
146 }
147 catch (Exception e)
148 {
149 throw new ServletException ("Cannot invoke action '" + actionDefinition.getAction() + "' in namespace '" + actionDefinition.getNamespace() + "'", e);
150 }
151 finally
152 {
153 if (null != stack)
155 {
156 request.setAttribute(ServletActionContext.WEBWORK_VALUESTACK_KEY, stack);
157 }
158 }
159 }
160
161 protected void prepareContinuationAction(HttpServletRequest request, Map extraContext)
162 {
163 String id = request.getParameter(XWorkContinuationConfig.CONTINUE_PARAM);
164 if (null != id)
165 {
166 Map params = (Map ) extraContext.get(ActionContext.PARAMETERS);
169 params.remove(XWorkContinuationConfig.CONTINUE_PARAM);
170
171 extraContext.put(XWorkContinuationConfig.CONTINUE_KEY, id);
173 }
174 }
175
176 protected ActionMapping getActionMapping(ActionDefinition actionDefinition, Map params)
177 {
178 ActionMapping actionMapping = new ActionMapping(actionDefinition.getAction(), actionDefinition.getNamespace(), actionDefinition.getMethod(), params);
179
180 return actionMapping;
181 }
182
183 protected AjaxTextResult getTextResult(FakeHttpServletResponse response)
184 {
185 DefaultAjaxTextResult result = new DefaultAjaxTextResult();
186
187 String text = null;
188 try
189 {
190 text = response.getContentAsString();
191 }
192 catch (UnsupportedEncodingException uee)
193 {
194 log.warn("Cannot retrieve text output as string", uee);
195 }
196
197 if (null == text)
198 {
199 try
200 {
201 text = response.getCharacterEncoding() != null ? new String (response.getContentAsByteArray(), response.getCharacterEncoding()) : new String (response.getContentAsByteArray());
202 }
203 catch (UnsupportedEncodingException uee)
204 {
205 log.warn("Cannot retrieve text output as encoded byte array", uee);
206 text = new String (response.getContentAsByteArray());
207 }
208 }
209
210 result.setText(text);
211 return result;
212 }
213
214
220 private static void initialize(ServletContext servletContext) throws ServletException
221 {
222 synchronized(DWRAction.class)
223 {
224 if (null == s_instance)
225 {
226 s_instance = new DWRAction(servletContext);
227 }
228 }
229 }
230
231
238 private static IDWRActionProcessor loadActionProcessor(String actionProcessorClassName) throws ServletException
239 {
240 if (null == actionProcessorClassName || "".equals(actionProcessorClassName))
241 {
242 return null;
243 }
244
245 try
246 {
247 Class actionProcessorClass = LocalUtil.classForName(actionProcessorClassName);
248
249 return (IDWRActionProcessor) actionProcessorClass.newInstance();
250 }
251 catch(ClassNotFoundException cnfe)
252 {
253 throw new ServletException ("Cannot load DWRActionProcessor class '" + actionProcessorClassName + "'", cnfe);
254 }
255 catch(IllegalAccessException iae)
256 {
257 throw new ServletException ("Cannot instantiate DWRActionProcessor class '" + actionProcessorClassName + "'. Default constructor is not visible", iae);
258 }
259 catch(InstantiationException ie)
260 {
261 throw new ServletException ("Cannot instantiate DWRActionProcessor class '" + actionProcessorClassName + "'. No default constructor found", ie);
262 }
263 catch(Throwable cause)
264 {
265 throw new ServletException ("Cannot instantiate DWRActionProcessor class '" + actionProcessorClassName + "'", cause);
266 }
267 }
268
269 }
270
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