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1
18 package org.apache.beehive.netui.pageflow.internal;
19
20 import org.apache.beehive.netui.pageflow.AutoRegisterActionServlet;
21 import org.apache.beehive.netui.pageflow.ServletContainerAdapter;
22 import org.apache.beehive.netui.pageflow.RequestContext;
23 import org.apache.beehive.netui.pageflow.handler.ReloadableClassHandler;
24 import org.apache.beehive.netui.util.internal.BouncyClassLoader;
25 import org.apache.beehive.netui.util.internal.cache.ClassLevelCache;
26 import org.apache.beehive.netui.util.logging.Logger;
27 import org.apache.beehive.netui.util.internal.DiscoveryUtils;
28
29 import javax.servlet.http.HttpSession  ;
30 import javax.servlet.ServletContext ;
31 import java.util.Enumeration ;
32 import java.util.Map ;
33 import org.apache.beehive.netui.util.internal.concurrent.InternalConcurrentHashMap;
34 import java.io.File ;
35
36 import org.apache.struts.action.ActionServlet;
37
38
39 public class DefaultReloadableClassHandler
40 extends DefaultHandler
41 implements ReloadableClassHandler
42 {
43 private static final Logger _log = Logger.getInstance( DefaultReloadableClassHandler.class );
44
45 private BouncyClassLoader _pageFlowClassLoader = null;
46
47 public DefaultReloadableClassHandler( ServletContext servletContext )
48 {
49 init( null, null, servletContext );
50
51 if ( false )
53 {
54 ClassLoader contextClassLoader = Thread.currentThread().getContextClassLoader();
55 ServletContainerAdapter servletContainerAdapter = AdapterManager.getServletContainerAdapter( servletContext );
56 File [] classDirs = null;
57
58 {
61 String path = servletContext.getRealPath( "/WEB-INF/classes" );
62
63 if ( path != null )
64 {
65 File file = new File ( path );
66 if ( file.isDirectory() ) classDirs = new File []{ file };
67 }
68 }
69
70 if ( classDirs != null && ! servletContainerAdapter.isInProductionMode() )
71 {
72 _pageFlowClassLoader = new BouncyClassLoader( classDirs, contextClassLoader );
73 }
74 }
75 }
76
77 public Object newInstance( String className )
78 throws ClassNotFoundException , InstantiationException , IllegalAccessException
79 {
80 return getRegisteredReloadableClassHandler().loadClass( className ).newInstance();
81 }
82
83 private static Map _loadedClasses = new InternalConcurrentHashMap();
84 private static class Null {}
85 private static Class NULL_CLASS = Null.class;
86
87 public Class loadCachedClass( String className )
88 {
89 Class clazz = ( Class ) _loadedClasses.get( className );
90
91 if ( clazz != null )
92 {
93 return clazz != NULL_CLASS ? clazz : null;
94 }
95 else
96 {
97 try
98 {
99 clazz = getRegisteredReloadableClassHandler().loadClass( className );
100 _loadedClasses.put( className, clazz );
101 return clazz;
102 }
103 catch ( ClassNotFoundException e )
104 {
105 _loadedClasses.put( className, NULL_CLASS );
106 return null;
107 }
108 }
109 }
110
111 public Class loadClass( String className )
112 throws ClassNotFoundException
113 {
114 if ( _pageFlowClassLoader != null )
115 {
116 synchronized ( this )
117 {
118 return _pageFlowClassLoader.loadClass( className );
119 }
120 }
121 else
122 {
123 return DiscoveryUtils.getClassLoader().loadClass( className );
124 }
125 }
126
127 public void reloadClasses( RequestContext context )
128 {
129 if ( _pageFlowClassLoader == null )
130 {
131 return;
132 }
133
134 synchronized ( this )
135 {
136 if ( _pageFlowClassLoader.isStale() )
137 {
138 _log.debug( "Classes modified; bouncing classloader." );
139
140 HttpSession session = InternalUtils.getHttpSession( context.getRequest(), false );
145
146 if ( session != null )
147 {
148 for ( Enumeration e = session.getAttributeNames(); e.hasMoreElements(); )
149 {
150 String attrName = ( String ) e.nextElement();
151 Object attr = session.getAttribute( attrName );
152 if ( attr.getClass().getClassLoader() == _pageFlowClassLoader )
153 {
154 if ( _log.isDebugEnabled() )
155 {
156 _log.debug( "Removing session attribute " + attrName + " (" + attr
157 + ") because its ClassLoader is being bounced." );
158 }
159
160 session.removeAttribute( attrName );
161 }
162 }
163 }
164
165 ClassLevelCache.clearAll();
169
170 ActionServlet actionServlet = InternalUtils.getActionServlet( getServletContext() );
174
175 if ( actionServlet instanceof AutoRegisterActionServlet )
176 {
177 ( ( AutoRegisterActionServlet ) actionServlet ).clearRegisteredModules();
178 }
179
180 init( getConfig(), getPreviousHandler(), getServletContext() );
184 }
185 }
186 }
187
188 public ClassLoader getClassLoader()
189 {
190 if ( _pageFlowClassLoader != null )
191 {
192 synchronized ( this )
193 {
194 return _pageFlowClassLoader;
195 }
196 }
197
198 return _pageFlowClassLoader;
199 }
200
201 public boolean isReloadEnabled()
202 {
203 return _pageFlowClassLoader != null;
204 }
205
206 public ReloadableClassHandler getRegisteredReloadableClassHandler()
207 {
208 return ( ReloadableClassHandler ) super.getRegisteredHandler();
209 }
210 }
211 |
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