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1
11 package org.eclipse.osgi.framework.internal.core;
12
13 import java.net.URL  ;
14 import java.util.*;
15 import org.osgi.framework.*;
16
17 public class PolicyHandler {
18 private final static String DEPENDENT_POLICY = "dependent"; private final static String GLOBAL_POLICY = "global"; private final static String REGISTERED_POLICY = "registered"; private final static String APP_POLICY = "app"; private final static String EXT_POLICY = "ext"; private final static String BOOT_POLICY = "boot"; private final static String PARENT_POLICY = "parent";
27 BundleLoader policedLoader;
29 Object [] policies = null;
31
32 private ThreadLocal beingLoaded;
34
35 private BundleListener listener = new BundleListener() {
36 public void bundleChanged(BundleEvent event) {
37 if (event.getType() == BundleEvent.STARTED || event.getType() == BundleEvent.STOPPED)
38 return;
39 try {
40 String list = (String ) policedLoader.getBundle().getBundleData().getManifest().get(Constants.BUDDY_LOADER);
41 synchronized (this) {
42 policies = getArrayFromList(list);
43 }
44 } catch (BundleException e) {
45 }
47 }
48 };
49
50 public PolicyHandler(BundleLoader loader, String buddyList) {
51 policedLoader = loader;
52 policies = getArrayFromList(buddyList);
53 beingLoaded = new ThreadLocal ();
54 policedLoader.bundle.framework.systemBundle.context.addBundleListener(listener);
55 }
56
57 static Object [] getArrayFromList(String stringList) {
58 if (stringList == null || stringList.trim().equals("")) return null;
60 Vector list = new Vector();
61 StringTokenizer tokens = new StringTokenizer(stringList, ","); while (tokens.hasMoreTokens()) {
63 String token = tokens.nextToken().trim();
64 if (!token.equals("")) list.addElement(token);
66 }
67 return list.isEmpty() ? new Object [0] : (Object []) list.toArray(new Object [list.size()]);
68 }
69
70 private synchronized IBuddyPolicy getPolicyImplementation(int policyOrder) {
71 if (policies[policyOrder] instanceof String ) {
72 String buddyName = (String ) policies[policyOrder];
73
74 if (REGISTERED_POLICY.equals(buddyName)) {
75 policies[policyOrder] = new RegisteredPolicy(policedLoader);
76 return (IBuddyPolicy) policies[policyOrder];
77 }
78 if (BOOT_POLICY.equals(buddyName)) {
79 policies[policyOrder] = SystemPolicy.getInstance(SystemPolicy.BOOT);
80 return (IBuddyPolicy) policies[policyOrder];
81 }
82 if (APP_POLICY.equals(buddyName)) {
83 policies[policyOrder] = SystemPolicy.getInstance(SystemPolicy.APP);
84 return (IBuddyPolicy) policies[policyOrder];
85 }
86 if (EXT_POLICY.equals(buddyName)) {
87 policies[policyOrder] = SystemPolicy.getInstance(SystemPolicy.EXT);
88 return (IBuddyPolicy) policies[policyOrder];
89 }
90 if (DEPENDENT_POLICY.equals(buddyName)) {
91 policies[policyOrder] = new DependentPolicy(policedLoader);
92 return (IBuddyPolicy) policies[policyOrder];
93 }
94 if (GLOBAL_POLICY.equals(buddyName)) {
95 policies[policyOrder] = new GlobalPolicy(policedLoader.bundle.framework.packageAdmin);
96 return (IBuddyPolicy) policies[policyOrder];
97 }
98 if (PARENT_POLICY.equals(buddyName)) {
99 policies[policyOrder] = new SystemPolicy(policedLoader.getParentClassLoader());
100 return (IBuddyPolicy) policies[policyOrder];
101 }
102
103 }
129 return (IBuddyPolicy) policies[policyOrder];
130 }
131
132 public Class doBuddyClassLoading(String name) {
133 if (startLoading(name) == false)
134 return null;
135
136 Class result = null;
137 for (int i = 0; i < policies.length && result == null; i++) {
138 result = getPolicyImplementation(i).loadClass(name);
139 }
140 stopLoading(name);
141 return result;
142 }
143
144 public URL doBuddyResourceLoading(String name) {
145 if (startLoading(name) == false)
146 return null;
147
148 if (policies == null)
149 return null;
150 URL result = null;
151 for (int i = 0; i < policies.length && result == null; i++) {
152 result = getPolicyImplementation(i).loadResource(name);
153 }
154 stopLoading(name);
155 return result;
156 }
157
158 public Enumeration doBuddyResourcesLoading(String name) {
159 if (startLoading(name) == false)
160 return null;
161
162 if (policies == null)
163 return null;
164 Vector results = null;
165 for (int i = 0; i < policies.length; i++) {
166 Enumeration result = getPolicyImplementation(i).loadResources(name);
167 if (result != null) {
168 if (results == null)
169 results = new Vector(policies.length);
170 while (result.hasMoreElements()) {
171 Object url = result.nextElement();
172 if (!results.contains(url)) results.add(url);
174 }
175 }
176 }
177 stopLoading(name);
178 return results == null || results.isEmpty() ? null : results.elements();
179 }
180
181 private boolean startLoading(String name) {
182 Set classesAndResources = (Set) beingLoaded.get();
183 if (classesAndResources != null && classesAndResources.contains(name))
184 return false;
185
186 if (classesAndResources == null) {
187 classesAndResources = new HashSet(3);
188 beingLoaded.set(classesAndResources);
189 }
190 classesAndResources.add(name);
191 return true;
192 }
193
194 private void stopLoading(String name) {
195 ((Set) beingLoaded.get()).remove(name);
196 }
197
198 public void close() {
199 policedLoader.bundle.framework.systemBundle.context.removeBundleListener(listener);
200 }
201 }
202 |
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