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1
11 package org.eclipse.core.runtime.internal.adaptor;
12
13 import java.io.File  ;
14 import java.io.IOException ;
15 import java.net.URL ;
16 import org.eclipse.osgi.framework.internal.core.FrameworkProperties;
17 import org.eclipse.osgi.service.datalocation.Location;
18
19
22 public class BasicLocation implements Location {
23 private static class MockLocker implements Locker {
24 public boolean lock() throws IOException {
25 return true;
27 }
28 public void release() {
29 }
31
32 }
33 private boolean isReadOnly;
34 private URL location = null;
35 private Location parent;
36 private URL defaultValue;
37 private String property;
38
39 private File lockFile;
41 private Locker locker;
42 public static final String PROP_OSGI_LOCKING = "osgi.locking"; private static String LOCK_FILENAME = ".metadata/.lock"; public static boolean DEBUG;
45
46 private static boolean isRunningWithNio() {
47 try {
48 Class.forName("java.nio.channels.FileLock"); } catch (ClassNotFoundException e) {
50 return false;
51 }
52 return true;
53 }
54
55 public static Locker createLocker(File lock, String lockMode) {
56 if (lockMode == null)
57 lockMode = FrameworkProperties.getProperty(PROP_OSGI_LOCKING);
58
59 if ("none".equals(lockMode)) return new MockLocker();
61
62 if ("java.io".equals(lockMode)) return new Locker_JavaIo(lock);
64
65 if ("java.nio".equals(lockMode)) { if (isRunningWithNio()) {
67 return new Locker_JavaNio(lock);
68 } else {
69 return new Locker_JavaIo(lock);
71 }
72 }
73
74 if (isRunningWithNio()) {
76 return new Locker_JavaNio(lock);
77 } else {
78 return new Locker_JavaIo(lock);
79 }
80 }
81
82 public BasicLocation(String property, URL defaultValue, boolean isReadOnly) {
83 super();
84 this.property = property;
85 this.defaultValue = defaultValue;
86 this.isReadOnly = isReadOnly;
87 }
88
89 public boolean allowsDefault() {
90 return defaultValue != null;
91 }
92
93 public URL getDefault() {
94 return defaultValue;
95 }
96
97 public Location getParentLocation() {
98 return parent;
99 }
100
101 public synchronized URL getURL() {
102 if (location == null && defaultValue != null)
103 setURL(defaultValue, false);
104 return location;
105 }
106
107 public synchronized boolean isSet() {
108 return location != null;
109 }
110
111 public boolean isReadOnly() {
112 return isReadOnly;
113 }
114
115 public synchronized boolean setURL(URL value, boolean lock) throws IllegalStateException {
116 if (location != null)
117 throw new IllegalStateException (EclipseAdaptorMsg.ECLIPSE_CANNOT_CHANGE_LOCATION);
118 File file = null;
119 if (value.getProtocol().equalsIgnoreCase("file")) { try {
121 String basePath = new File (value.getFile()).getCanonicalPath();
122 value = new URL ("file:" + basePath); } catch (IOException e) {
124 }
126 file = new File (value.getFile(), LOCK_FILENAME);
127 }
128 lock = lock && !isReadOnly;
129 if (lock) {
130 try {
131 if (!lock(file))
132 return false;
133 } catch (IOException e) {
134 return false;
135 }
136 }
137 lockFile = file;
138 location = LocationHelper.buildURL(value.toExternalForm(), true);
139 if (property != null)
140 FrameworkProperties.setProperty(property, location.toExternalForm());
141 return lock;
142 }
143
144 public synchronized void setParent(Location value) {
145 parent = value;
146 }
147
148 public synchronized boolean lock() throws IOException {
149 if (!isSet())
150 return false;
151 return lock(lockFile);
152 }
153
154 private boolean lock(File lock) throws IOException {
155 if (lock == null || isReadOnly)
156 return false;
157
158 File parentFile = new File (lock.getParent());
159 if (!parentFile.exists())
160 if (!parentFile.mkdirs())
161 return false;
162
163 setLocker(lock);
164 if (locker == null)
165 return true;
166 boolean locked = false;
167 try {
168 locked = locker.lock();
169 return locked;
170 } finally {
171 if (!locked)
172 locker = null;
173 }
174 }
175
176 private void setLocker(File lock) {
177 if (locker != null)
178 return;
179 String lockMode = FrameworkProperties.getProperty(PROP_OSGI_LOCKING);
180 locker = createLocker(lock, lockMode);
181 }
182
183 public synchronized void release() {
184 if (locker != null)
185 locker.release();
186 }
187 }
188 |
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