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1
19
20 package org.netbeans.modules.ruby.modules.project.rake;
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 <FileChangeSupportListener,Map <File ,Holder>> holders = new WeakHashMap <FileChangeSupportListener,Map <File ,Holder>>();
55
56
63 public void addListener(FileChangeSupportListener listener, File path) {
64 assert path.equals(FileUtil.normalizeFile(path)) : "Need to normalize " + path + " before passing to FCS!";
65 Map <File ,Holder> f2H = holders.get(listener);
66 if (f2H == null) {
67 f2H = new HashMap <File ,Holder>();
68 holders.put(listener, f2H);
69 }
70 if (f2H.containsKey(path)) {
71 throw new IllegalArgumentException ("Already listening to " + path); }
73 f2H.put(path, new Holder(listener, path));
74 }
75
76
79 public void removeListener(FileChangeSupportListener listener, File path) {
80 assert path.equals(FileUtil.normalizeFile(path)) : "Need to normalize " + path + " before passing to FCS!";
81 Map <File ,Holder> f2H = holders.get(listener);
82 if (f2H == null) {
83 throw new IllegalArgumentException ("Was not listening to " + path); }
85 if (!f2H.containsKey(path)) {
86 throw new IllegalArgumentException ("Was not listening to " + path); }
88 f2H.remove(path);
89 }
90
91 private static final class Holder extends WeakReference <FileChangeSupportListener> implements FileChangeListener, Runnable {
92
93 private final File path;
94 private FileObject current;
95 private File currentF;
96
97 public Holder(FileChangeSupportListener listener, File path) {
98 super(listener, Utilities.activeReferenceQueue());
99 assert path != null;
100 this.path = path;
101 locateCurrent();
102 }
103
104 private void locateCurrent() {
105 FileObject oldCurrent = current;
106 currentF = path;
107 while (true) {
108 try {
109 current = FileUtil.toFileObject(currentF);
110 } catch (IllegalArgumentException x) {
111 currentF = FileUtil.normalizeFile(currentF);
113 current = FileUtil.toFileObject(currentF);
114 }
115 if (current != null) {
116 break;
117 }
118 currentF = currentF.getParentFile();
119 if (currentF == null) {
120 return;
123 }
124 }
125 assert current != null;
127 if (current != oldCurrent) {
128 if (oldCurrent != null) {
129 oldCurrent.removeFileChangeListener(this);
130 }
131 current.addFileChangeListener(this);
132 current.getChildren(); }
134 }
135
136 private void someChange(FileObject modified) {
137 FileChangeSupportListener listener;
138 FileObject oldCurrent, nueCurrent;
139 File oldCurrentF, nueCurrentF;
140 synchronized (this) {
141 if (current == null) {
142 return;
143 }
144 listener = get();
145 if (listener == null) {
146 return;
147 }
148 oldCurrent = current;
149 oldCurrentF = currentF;
150 locateCurrent();
151 nueCurrent = current;
152 nueCurrentF = currentF;
153 }
154 if (modified != null && modified == nueCurrent) {
155 FileChangeSupportEvent event = new FileChangeSupportEvent(DEFAULT, FileChangeSupportEvent.EVENT_MODIFIED, path);
156 listener.fileModified(event);
157 } else {
158 boolean oldWasCorrect = path.equals(oldCurrentF);
159 boolean nueIsCorrect = path.equals(nueCurrentF);
160 if (oldWasCorrect && !nueIsCorrect) {
161 FileChangeSupportEvent event = new FileChangeSupportEvent(DEFAULT, FileChangeSupportEvent.EVENT_DELETED, path);
162 listener.fileDeleted(event);
163 } else if (nueIsCorrect && !oldWasCorrect) {
164 FileChangeSupportEvent event = new FileChangeSupportEvent(DEFAULT, FileChangeSupportEvent.EVENT_CREATED, path);
165 listener.fileCreated(event);
166 }
167 }
168 }
169
170 public void fileChanged(FileEvent fe) {
171 someChange(fe.getFile());
172 }
173
174 public void fileDeleted(FileEvent fe) {
175 someChange(null);
176 }
177
178 public void fileDataCreated(FileEvent fe) {
179 someChange(null);
180 }
181
182 public void fileFolderCreated(FileEvent fe) {
183 someChange(null);
184 }
185
186 public void fileRenamed(FileRenameEvent fe) {
187 someChange(null);
188 }
189
190 public void fileAttributeChanged(FileAttributeEvent fe) {
191 }
193
194 public synchronized void run() {
195 if (current != null) {
196 current.removeFileChangeListener(this);
197 current = null;
198 }
199 }
200
201 }
202
203 }
204 |
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