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1
11 package org.eclipse.team.internal.core;
12
13 import java.io.File  ;
14 import java.util.*;
15
16 import org.eclipse.core.runtime.IPath;
17 import org.eclipse.core.runtime.jobs.ILock;
18 import org.eclipse.core.runtime.jobs.Job;
19 import org.eclipse.osgi.util.NLS;
20 import org.eclipse.team.core.TeamException;
21 import org.eclipse.team.core.variants.CachedResourceVariant;
22
23
26 public class ResourceVariantCache {
27
28 private static final String CACHE_DIRECTORY = ".cache"; private static final long CACHE_FILE_LIFESPAN = 60*60*1000;
33 private static Map caches = new HashMap();
36 private String name;
37 private Map cacheEntries;
38 private long lastCacheCleanup;
39 private int cacheDirSize;
40
41 private ILock lock = Job.getJobManager().newLock();
43
44
50 public static synchronized void enableCaching(String cacheId) {
51 if (isCachingEnabled(cacheId)) return;
52 ResourceVariantCache cache = new ResourceVariantCache(cacheId);
53 cache.createCacheDirectory();
54 caches.put(cacheId, cache);
55 }
56
57
65 public static boolean isCachingEnabled(String cacheId) {
66 return getCache(cacheId) != null;
67 }
68
69
74 public static void disableCache(String cacheId) {
75 ResourceVariantCache cache = getCache(cacheId);
76 if (cache == null) {
77 return;
79 }
80 caches.remove(cacheId);
81 cache.deleteCacheDirectory();
82 }
83
84
89 public static synchronized ResourceVariantCache getCache(String cacheId) {
90 return (ResourceVariantCache)caches.get(cacheId);
91 }
92
93 public static synchronized void shutdown() {
94 String [] keys = (String [])caches.keySet().toArray(new String [caches.size()]);
95 for (int i = 0; i < keys.length; i++) {
96 String id = keys[i];
97 disableCache(id);
98 }
99 }
100
101 private ResourceVariantCache(String name) {
102 this.name = name;
103 }
104
105
110 public boolean hasEntry(String id) {
111 return internalGetCacheEntry(id) != null;
112 }
113
114 protected IPath getCachePath() {
115 return getStateLocation().append(CACHE_DIRECTORY).append(name);
116 }
117
118 private IPath getStateLocation() {
119 return TeamPlugin.getPlugin().getStateLocation();
120 }
121
122 private synchronized void clearOldCacheEntries() {
123 long current = new Date().getTime();
124 if ((lastCacheCleanup!=-1) && (current - lastCacheCleanup < CACHE_FILE_LIFESPAN)) return;
125 List stale = new ArrayList();
126 for (Iterator iter = cacheEntries.values().iterator(); iter.hasNext();) {
127 ResourceVariantCacheEntry entry = (ResourceVariantCacheEntry) iter.next();
128 long lastHit = entry.getLastAccessTimeStamp();
129 if ((current - lastHit) > CACHE_FILE_LIFESPAN){
130 stale.add(entry);
131 }
132 }
133 for (Iterator iter = stale.iterator(); iter.hasNext();) {
134 ResourceVariantCacheEntry entry = (ResourceVariantCacheEntry) iter.next();
135 entry.dispose();
136 }
137 }
138
139 private synchronized void purgeFromCache(String id) {
140 ResourceVariantCacheEntry entry = (ResourceVariantCacheEntry)cacheEntries.get(id);
141 File f = entry.getFile();
142 try {
143 deleteFile(f);
144 } catch (TeamException e) {
145 }
148 cacheEntries.remove(id);
149 }
150
151 private synchronized void createCacheDirectory() {
152 IPath cacheLocation = getCachePath();
153 File file = cacheLocation.toFile();
154 if (file.exists()) {
155 try {
156 deleteFile(file);
157 } catch (TeamException e) {
158 if (file.exists() && (!file.isDirectory() || file.listFiles().length != 0)) {
160 TeamPlugin.log(e);
161 }
162 }
163 }
164 if (! file.exists() && ! file.mkdirs()) {
165 TeamPlugin.log(new TeamException(NLS.bind(Messages.RemoteContentsCache_fileError, new String [] { file.getAbsolutePath() })));
166 }
167 cacheEntries = new HashMap();
168 lastCacheCleanup = -1;
169 cacheDirSize = 0;
170 }
171
172 private synchronized void deleteCacheDirectory() {
173 cacheEntries = null;
174 lastCacheCleanup = -1;
175 cacheDirSize = 0;
176 IPath cacheLocation = getCachePath();
177 File file = cacheLocation.toFile();
178 if (file.exists()) {
179 try {
180 deleteFile(file);
181 } catch (TeamException e) {
182 }
185 }
186 }
187
188 private void deleteFile(File file) throws TeamException {
189 if (file.isDirectory()) {
190 File [] children = file.listFiles();
191 for (int i = 0; i < children.length; i++) {
192 deleteFile(children[i]);
193 }
194 }
195 if (! file.delete()) {
196 throw new TeamException(NLS.bind(Messages.RemoteContentsCache_fileError, new String [] { file.getAbsolutePath() }));
197 }
198 }
199
200
205 protected void purgeFromCache(ResourceVariantCacheEntry entry) {
206 purgeFromCache(entry.getId());
207 }
208
209 private synchronized ResourceVariantCacheEntry internalGetCacheEntry(String id) {
210 if (cacheEntries == null) {
211 throw new IllegalStateException (NLS.bind(Messages.RemoteContentsCache_cacheDisposed, new String [] { name }));
213 }
214 ResourceVariantCacheEntry entry = (ResourceVariantCacheEntry)cacheEntries.get(id);
215 if (entry != null) {
216 entry.registerHit();
217 }
218 return entry;
219 }
220
221
225 public ResourceVariantCacheEntry getCacheEntry(String id) {
226 return internalGetCacheEntry(id);
227 }
228
229 public synchronized ResourceVariantCacheEntry add(String id, CachedResourceVariant resource) {
230 clearOldCacheEntries();
231 String filePath = String.valueOf(cacheDirSize++);
232 ResourceVariantCacheEntry entry = new ResourceVariantCacheEntry(this, lock, id, filePath);
233 entry.setResourceVariant(resource);
234 cacheEntries.put(id, entry);
235 return entry;
236 }
237
238 public String getName() {
239 return name;
240 }
241
242
245 public ResourceVariantCacheEntry[] getEntries() {
246 return (ResourceVariantCacheEntry[]) cacheEntries.values().toArray(new ResourceVariantCacheEntry[cacheEntries.size()]);
247 }
248
249 }
250 |
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