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1
19
20 package org.netbeans.modules.j2ee.persistenceapi;
21
22 import java.io.File  ;
23 import java.util.Map ;
24 import java.util.WeakHashMap ;
25 import org.openide.filesystems.FileObject;
26 import java.lang.ref.Reference ;
27 import java.lang.ref.WeakReference ;
28 import java.util.HashMap ;
29
30 import org.openide.filesystems.FileChangeListener;
31 import org.openide.filesystems.FileAttributeEvent;
32 import org.openide.filesystems.FileEvent;
33 import org.openide.filesystems.FileRenameEvent;
34 import org.openide.filesystems.FileUtil;
35 import org.openide.util.Utilities;
36
37
39
48 public final class FileChangeSupport {
49
50 public static FileChangeSupport DEFAULT = new FileChangeSupport();
51
52 private FileChangeSupport() {}
53
54 private final Map holders = new WeakHashMap ();
55
56 public static FileChangeSupport getDefault() {
57 return DEFAULT;
58 }
59
60
67 public void addListener(FileChangeSupportListener listener, File path) {
68 assert path.equals(FileUtil.normalizeFile(path)) : "Need to normalize " + path + " before passing to FCS!";
69 Map f2H = (Map ) holders.get(listener);
70 if (f2H == null) {
71 f2H = new HashMap ();
72 holders.put(listener, f2H);
73 }
74 if (f2H.containsKey(path)) {
75 throw new IllegalArgumentException ("Already listening to " + path); }
77 f2H.put(path, new Holder(listener, path));
78 }
79
80
83 public void removeListener(FileChangeSupportListener listener, File path) {
84 assert path.equals(FileUtil.normalizeFile(path)) : "Need to normalize " + path + " before passing to FCS!";
85 Map f2H = (Map ) holders.get(listener);
86 if (f2H == null) {
87 throw new IllegalArgumentException ("Was not listening to " + path); }
89 if (!f2H.containsKey(path)) {
90 throw new IllegalArgumentException ("Was not listening to " + path); }
92 f2H.remove(path);
93 }
94
95 private static final class Holder extends WeakReference implements FileChangeListener, Runnable {
96
97 private final File path;
98 private FileObject current;
99 private File currentF;
100
101 public Holder(FileChangeSupportListener listener, File path) {
102 super(listener, Utilities.activeReferenceQueue());
103 assert path != null;
104 this.path = path;
105 locateCurrent();
106 }
107
108 private void locateCurrent() {
109 FileObject oldCurrent = current;
110 currentF = path;
111 while (true) {
112 current = FileUtil.toFileObject(currentF);
113 if (current != null) {
114 break;
115 }
116 currentF = currentF.getParentFile();
117 if (currentF == null) {
118 return;
121 }
122 }
123 assert current != null;
125 if (current != oldCurrent) {
126 if (oldCurrent != null) {
127 oldCurrent.removeFileChangeListener(this);
128 }
129 current.addFileChangeListener(this);
130 current.getChildren(); }
132 }
133
134 private void someChange(FileObject modified) {
135 FileChangeSupportListener listener;
136 FileObject oldCurrent, nueCurrent;
137 File oldCurrentF, nueCurrentF;
138 synchronized (this) {
139 if (current == null) {
140 return;
141 }
142 listener = (FileChangeSupportListener) get();
143 if (listener == null) {
144 return;
145 }
146 oldCurrent = current;
147 oldCurrentF = currentF;
148 locateCurrent();
149 nueCurrent = current;
150 nueCurrentF = currentF;
151 }
152 if (modified != null && modified == nueCurrent) {
153 FileChangeSupportEvent event = new FileChangeSupportEvent(DEFAULT, FileChangeSupportEvent.EVENT_MODIFIED, path);
154 listener.fileModified(event);
155 } else {
156 boolean oldWasCorrect = path.equals(oldCurrentF);
157 boolean nueIsCorrect = path.equals(nueCurrentF);
158 if (oldWasCorrect && !nueIsCorrect) {
159 FileChangeSupportEvent event = new FileChangeSupportEvent(DEFAULT, FileChangeSupportEvent.EVENT_DELETED, path);
160 listener.fileDeleted(event);
161 } else if (nueIsCorrect && !oldWasCorrect) {
162 FileChangeSupportEvent event = new FileChangeSupportEvent(DEFAULT, FileChangeSupportEvent.EVENT_CREATED, path);
163 listener.fileCreated(event);
164 }
165 }
166 }
167
168 public void fileChanged(FileEvent fe) {
169 someChange(fe.getFile());
170 }
171
172 public void fileDeleted(FileEvent fe) {
173 someChange(null);
174 }
175
176 public void fileDataCreated(FileEvent fe) {
177 someChange(null);
178 }
179
180 public void fileFolderCreated(FileEvent fe) {
181 someChange(null);
182 }
183
184 public void fileRenamed(FileRenameEvent fe) {
185 someChange(null);
186 }
187
188 public void fileAttributeChanged(FileAttributeEvent fe) {
189 }
191
192 public synchronized void run() {
193 if (current != null) {
194 current.removeFileChangeListener(this);
195 current = null;
196 }
197 }
198
199 }
200
201 }
202 |
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