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1 package org.objectweb.celtix.resource;
2
3 import java.io.InputStream  ;
4 import java.util.LinkedList ;
5 import java.util.List ;
6 import java.util.logging.Level ;
7 import java.util.logging.Logger ;
8
9 import org.objectweb.celtix.common.logging.LogUtils;
10
11 public class DefaultResourceManager implements ResourceManager {
12
13 private static final Logger LOG = LogUtils.getL7dLogger(DefaultResourceManager.class);
14 private static ResourceManager instance;
15
16 protected final List <ResourceResolver> resolvers = new LinkedList <ResourceResolver>();
17
18
19 public DefaultResourceManager() {
20 initializeDefaultResolvers();
21 }
22
23 public final <T> T resolveResource(String name, Class <T> type) {
24 return findResource(name, type, false);
25 }
26
27
28 public final InputStream getResourceAsStream(String name) {
29 return findResource(name, InputStream .class, true);
30 }
31
32
33 public final void addResourceResolver(ResourceResolver resolver) {
34 if (!resolvers.contains(resolver)) {
35 resolvers.add(0, resolver);
36 }
37 }
38
39 public final void removeResourceResolver(ResourceResolver resolver) {
40 if (resolvers.contains(resolver)) {
41 resolvers.remove(resolver);
42 }
43 }
44
45
46 public final List getResourceResolvers() {
47 return resolvers;
48 }
49
50
51 private <T> T findResource(String name, Class <T> type, boolean asStream) {
52 if (LOG.isLoggable(Level.FINE)) {
53 LOG.fine("resolving resource <" + name + ">" + (asStream ? " as stream "
54 : " type <" + type + ">"));
55 }
56
57 T ret = null;
58 for (ResourceResolver rr : resolvers) {
59 if (asStream) {
60 ret = type.cast(rr.getAsStream(name));
61 } else {
62 ret = rr.resolve(name, type);
63 }
64 if (ret != null) {
65 break;
66 }
67 }
68 return ret;
69 }
70
71
72 public static synchronized ResourceManager instance() {
73 if (instance == null) {
74 instance = new DefaultResourceManager();
75 }
76 return instance;
77 }
78 public static synchronized void clearInstance() {
79 instance = null;
80 }
81
82 private void initializeDefaultResolvers() {
83 addResourceResolver(new ClasspathResolver());
84 addResourceResolver(new ClassLoaderResolver(getClass().getClassLoader()));
85 }
86
87 }
88 |
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