|
1
29
30 package javax.xml.bind;
31 import java.io.File  ;
32 import java.io.FileInputStream ;
33 import java.io.IOException ;
34 import java.io.InputStream ;
35 import java.net.URL ;
36 import java.util.ArrayList ;
37 import java.util.Enumeration ;
38 import java.util.HashMap ;
39 import java.util.Properties ;
40 import java.util.WeakHashMap ;
41 import java.util.logging.Level ;
42 import java.util.logging.Logger ;
43
44 class FactoryLoader {
45 private static Logger log =
46 Logger.getLogger("javax.xml.bind.FactoryLoader");
47
48 private static HashMap <String ,FactoryLoader> _factoryLoaders
49 = new HashMap <String ,FactoryLoader>();
50
51 private String _factoryId;
52
53 private WeakHashMap <ClassLoader ,Object []> _providerMap
54 = new WeakHashMap <ClassLoader ,Object []>();
55
56 public static FactoryLoader getFactoryLoader(String factoryId) {
57
58 FactoryLoader ret = _factoryLoaders.get(factoryId);
59
60 if (ret == null) {
61 ret = new FactoryLoader(factoryId);
62 _factoryLoaders.put(factoryId, ret);
63 }
64
65 return ret;
66 }
67
68 private FactoryLoader(String factoryId)
69 {
70 _factoryId = factoryId;
71 }
72
73 public Object newInstance(ClassLoader classLoader)
74 throws FactoryConfigurationError
75 {
76 String className = null;
77
78 className = System.getProperty(_factoryId);
79
80 if (className == null) {
81 String fileName =
82 System.getProperty("java.home") +
83 File.separatorChar +
84 "lib" +
85 File.separatorChar +
86 "jaxb.properties";
87
88 FileInputStream is = null;
89 try {
90 is = new FileInputStream (new File (fileName));
91
92 Properties props = new Properties ();
93 props.load(is);
94
95 className = props.getProperty(_factoryId);
96
97 }
98 catch (IOException e) {
99 log.log(Level.FINER, "ignoring exception", e);
100 }
101 finally {
102 if (is != null)
103 try {
104 is.close();
105 } catch (IOException e) {
106 log.log(Level.FINER, "ignoring exception", e);
107 }
108 }
109 }
110
111 if (className == null) {
112 Object factory = createFactory("META-INF/services/"+_factoryId,
113 classLoader);
114 if (factory != null)
115 return factory;
116 }
117
118 if (className != null) {
119
120 try {
121 return classLoader.loadClass(className).newInstance();
122 }
123 catch (Exception e) {
124 throw new FactoryConfigurationError(e);
125 }
126 }
127
128 return null;
129 }
130
131 public Object createFactory(String name, ClassLoader loader)
132 {
133 Object [] providers = getProviderList(name, loader);
134
135 for (int i = 0; i < providers.length; i++) {
136 Object factory;
137
138 factory = providers[i];
139
140 if (factory != null)
141 return factory;
142 }
143
144 return null;
145 }
146
147 private Object []getProviderList(String service, ClassLoader loader)
148 {
149
150 Object []providers = _providerMap.get(loader);
151
152 if (providers != null)
153 return providers;
154
155 ArrayList <Object > list = new ArrayList <Object >();
156
157 try {
158 Enumeration e = loader.getResources(service);
159
160 while (e.hasMoreElements()) {
161 URL url = (URL ) e.nextElement();
162
163 Object provider = loadProvider(url, loader);
164
165 if (provider != null)
166 list.add(provider);
167 }
168 } catch (Throwable e) {
169 log.log(Level.WARNING, e.toString(), e);
170 }
171
172 providers = new Object [list.size()];
173 list.toArray(providers);
174
175 _providerMap.put(loader, providers);
176
177 return providers;
178 }
179
180 private Object loadProvider(URL url, ClassLoader loader)
181 {
182 InputStream is = null;
183 try {
184 is = url.openStream();
185 int ch;
186
187 while ((ch = is.read()) >= 0) {
188 if (Character.isWhitespace((char) ch)) {
189 }
190 else if (ch == '#') {
191 for (; ch >= 0 && ch != '\n' && ch != '\r'; ch = is.read()) {
192 }
193 }
194 else {
195 StringBuilder sb = new StringBuilder ();
196
197 for (;
198 ch >= 0 && ! Character.isWhitespace((char) ch);
199 ch = is.read()) {
200 sb.append((char) ch);
201 }
202
203 String className = sb.toString();
204
205 Class cl = Class.forName(className, false, loader);
206
207 return (Object ) cl.newInstance();
208 }
209 }
210 } catch (Throwable e) {
211 log.log(Level.WARNING, e.toString(), e);
212 } finally {
213 try {
214 if (is != null)
215 is.close();
216 } catch (Throwable e) {
217 }
218 }
219
220 return null;
221 }
222 }
223
224
225 |
Popular Tags |
Java API By Example, From Geeks To Geeks.