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1
18 package org.apache.beehive.netui.pageflow.handler;
19
20 import org.apache.beehive.netui.util.internal.DiscoveryUtils;
21 import org.apache.beehive.netui.util.config.bean.CustomProperty;
22 import org.apache.beehive.netui.util.config.bean.NetuiConfigDocument;
23 import org.apache.beehive.netui.util.config.bean.PageflowHandlers;
24 import org.apache.beehive.netui.util.config.ConfigUtil;
25 import org.apache.beehive.netui.util.logging.Logger;
26 import org.apache.beehive.netui.pageflow.internal.InternalConstants;
27 import org.apache.beehive.netui.pageflow.internal.DefaultLoginHandler;
28 import org.apache.beehive.netui.pageflow.internal.DefaultForwardRedirectHandler;
29 import org.apache.beehive.netui.pageflow.internal.DefaultReloadableClassHandler;
30 import org.apache.beehive.netui.pageflow.internal.DefaultExceptionsHandler;
31 import org.apache.beehive.netui.pageflow.internal.DefaultActionForwardHandler;
32 import org.apache.beehive.netui.pageflow.internal.DefaultHandler;
33 import org.apache.beehive.netui.pageflow.PageFlowActionServlet;
34 import org.apache.beehive.netui.pageflow.PageFlowContextListener;
35
36 import javax.servlet.ServletContext  ;
37 import java.io.Serializable ;
38
39
42 public class Handlers
43 implements Serializable
44 {
45 private static final Logger _log = Logger.getInstance( Handlers.class );
46
47 private static final String CONTEXT_ATTR = InternalConstants.ATTR_PREFIX + "_handlers";
48
49 private ActionForwardHandler _actionForwardHandler = null;
50 private ExceptionsHandler _exceptionsHandler = null;
51 private ForwardRedirectHandler _forwardRedirectHandler = null;
52 private LoginHandler _loginHandler = null;
53 private ReloadableClassHandler _reloadableClassHandler = null;
54 private transient ServletContext _servletContext;
55
56 public static Handlers get( ServletContext servletContext )
57 {
58 Handlers handlers = ( Handlers ) servletContext.getAttribute( CONTEXT_ATTR );
59
60 if ( handlers == null )
61 {
62 if ( _log.isErrorEnabled() )
63 {
64 _log.error( "Page Flow Handlers not initialized; either "
65 + PageFlowActionServlet.class.getName() + " must be the Struts action servlet, or "
66 + PageFlowContextListener.class.getName() + " must be registered as a listener in web.xml." );
67 }
68
69 return init( servletContext );
74 }
75
76 handlers.reinit( servletContext );
77 return handlers;
78 }
79
80 public static Handlers init( ServletContext servletContext )
81 {
82 assert servletContext.getAttribute( CONTEXT_ATTR ) == null : Handlers.class.getName() + " already initialized.";
83 Handlers handlers = new Handlers( servletContext );
84 servletContext.setAttribute( CONTEXT_ATTR, handlers );
85 return handlers;
86 }
87
88 private Handlers( ServletContext servletContext )
89 {
90 _servletContext = servletContext;
91
92 NetuiConfigDocument.NetuiConfig netuiConfig = ConfigUtil.getConfig();
96 PageflowHandlers handlers = netuiConfig.getPageflowHandlers();
97
98 DefaultHandler defaultActionForwardHandler = new DefaultActionForwardHandler( servletContext );
99 DefaultHandler defaultExceptionsHandler = new DefaultExceptionsHandler( servletContext );
100 DefaultHandler defaultForwardRedirectHandler = new DefaultForwardRedirectHandler( servletContext );
101 DefaultHandler defaultLoginHandler = new DefaultLoginHandler( servletContext );
102 DefaultHandler defaultReloadableClassHandler = new DefaultReloadableClassHandler( servletContext );
103
104 _actionForwardHandler = ( ActionForwardHandler )
105 adaptHandler( handlers != null ? handlers.getActionForwardHandlerArray() : null,
106 defaultActionForwardHandler, ActionForwardHandler.class, servletContext );
107
108 _exceptionsHandler = ( ExceptionsHandler )
109 adaptHandler( handlers != null ? handlers.getExceptionsHandlerArray() : null, defaultExceptionsHandler,
110 ExceptionsHandler.class, servletContext );
111
112 _forwardRedirectHandler = ( ForwardRedirectHandler )
113 adaptHandler( handlers != null ? handlers.getForwardRedirectHandlerArray() : null,
114 defaultForwardRedirectHandler, ForwardRedirectHandler.class, servletContext );
115
116 _loginHandler = ( LoginHandler )
117 adaptHandler( handlers != null ? handlers.getLoginHandlerArray() : null, defaultLoginHandler,
118 LoginHandler.class, servletContext );
119
120 _reloadableClassHandler = ( ReloadableClassHandler )
121 adaptHandler( handlers != null ? handlers.getReloadableClassHandlerArray() : null,
122 defaultReloadableClassHandler, ReloadableClassHandler.class, servletContext );
123 }
124
125 public void reinit( ServletContext servletContext )
126 {
127 if ( _servletContext == null )
128 {
129 _servletContext = servletContext;
130 _actionForwardHandler.reinit( servletContext );
131 _exceptionsHandler.reinit( servletContext );
132 _forwardRedirectHandler.reinit( servletContext );
133 _loginHandler.reinit( servletContext );
134 _reloadableClassHandler.reinit( servletContext );
135 }
136 }
137
138 public ActionForwardHandler getActionForwardHandler()
139 {
140 return _actionForwardHandler;
141 }
142
143 public ExceptionsHandler getExceptionsHandler()
144 {
145 return _exceptionsHandler;
146 }
147
148 public ForwardRedirectHandler getForwardRedirectHandler()
149 {
150 return _forwardRedirectHandler;
151 }
152
153 public LoginHandler getLoginHandler()
154 {
155 return _loginHandler;
156 }
157
158 public ReloadableClassHandler getReloadableClassHandler()
159 {
160 return _reloadableClassHandler;
161 }
162
163 private static Handler adaptHandler( org.apache.beehive.netui.util.config.bean.Handler[] handlerBeanConfigs,
164 DefaultHandler defaultHandler, Class baseClassOrInterface,
165 ServletContext servletContext )
166 {
167 Handler retVal = defaultHandler;
168
169 if ( handlerBeanConfigs != null )
170 {
171 for ( int i = 0; i < handlerBeanConfigs.length; i++ )
172 {
173 String handlerClass = handlerBeanConfigs[i].getHandlerClass();
174 CustomProperty[] props = handlerBeanConfigs[i].getCustomPropertyArray();
175 Handler handler = createHandler( handlerClass, baseClassOrInterface, retVal, servletContext );
176
177 if ( handler != null )
178 {
179 HandlerConfig config = new HandlerConfig( handlerClass );
180
181 for ( int j = 0; j < props.length; j++ )
182 {
183 CustomProperty prop = props[j];
184 config.addCustomProperty( prop.getName(), prop.getValue() );
185 }
186
187 handler.init( config, retVal, servletContext );
188 retVal = handler;
189 }
190 }
191 }
192
193 defaultHandler.setRegisteredHandler( retVal );
194 return retVal;
195 }
196
197
204 private static Handler createHandler( String className, Class baseClassOrInterface, Handler previousHandler,
205 ServletContext servletContext )
206 {
207 assert Handler.class.isAssignableFrom( baseClassOrInterface )
208 : baseClassOrInterface.getName() + " cannot be assigned to " + Handler.class.getName();
209
210 ClassLoader cl = DiscoveryUtils.getClassLoader();
211
212 try
213 {
214 Class handlerClass = cl.loadClass( className );
215
216 if ( ! baseClassOrInterface.isAssignableFrom( handlerClass ) )
217 {
218 _log.error( "Handler " + handlerClass.getName() + " does not implement or extend "
219 + baseClassOrInterface.getName() );
220 return null;
221 }
222
223 Handler handler = ( Handler ) handlerClass.newInstance();
224 return handler;
225 }
226 catch ( ClassNotFoundException e )
227 {
228 _log.error( "Could not find Handler class " + className, e );
229 }
230 catch ( InstantiationException e )
231 {
232 _log.error( "Could not instantiate Handler class " + className, e );
233 }
234 catch ( IllegalAccessException e )
235 {
236 _log.error( "Could not instantiate Handler class " + className, e );
237 }
238
239 return null;
240 }
241 }
242 |
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