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1
29
30 package javax.xml.stream;
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.stream.FactoryLoader");
47
48 private static HashMap <String ,FactoryLoader>
49 _factoryLoaders = new HashMap <String ,FactoryLoader>();
50
51 private String _factoryId;
52
53 private WeakHashMap <ClassLoader ,Class []>
54 _providerMap = new WeakHashMap <ClassLoader ,Class []>();
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 this._factoryId = factoryId;
71 }
72
73 public Object newInstance(ClassLoader classLoader)
74 throws FactoryConfigurationError
75 {
76 Class cl = newClass(classLoader);
77
78 if (cl != null) {
79 try {
80 return cl.newInstance();
81 }
82 catch (Exception e) {
83 throw new FactoryConfigurationError(e);
84 }
85 }
86
87 return null;
88 }
89
90 public Class newClass(ClassLoader classLoader)
91 throws FactoryConfigurationError
92 {
93 String className = null;
94
95 className = System.getProperty(_factoryId);
96
97 if (className == null) {
98
99 String fileName = (System.getProperty("java.home")
100 + File.separatorChar
101 + "lib"
102 + File.separatorChar
103 + "stax.properties");
104
105 FileInputStream is = null;
106 try {
107 is = new FileInputStream (new File (fileName));
108
109 Properties props = new Properties ();
110 props.load(is);
111
112 className = props.getProperty(_factoryId);
113 } catch (IOException e) {
114 log.log(Level.FINEST, "ignoring exception", e);
115 }
116 finally {
117 if (is != null)
118 try {
119 is.close();
120 } catch (IOException e) {
121 log.log(Level.FINER, "ignoring exception", e);
122 }
123 }
124 }
125
126 if (className == null) {
127 Class cl = createFactoryClass("META-INF/services/"+_factoryId,
128 classLoader);
129 if (cl != null)
130 return cl;
131 }
132
133 if (className != null) {
134 try {
135 return classLoader.loadClass(className);
136 }
137 catch (Exception e) {
138 throw new FactoryConfigurationError(e);
139 }
140 }
141
142 return null;
143 }
144
145 public Class createFactoryClass(String name, ClassLoader loader)
146 {
147 Class [] providers = getProviderList(name, loader);
148
149 for (int i = 0; i < providers.length; i++) {
150 Class factory;
151
152 factory = providers[i];
153
154 if (factory != null)
155 return factory;
156 }
157
158 return null;
159 }
160
161 private Class []getProviderList(String service, ClassLoader loader)
162 {
163 Class []providers = _providerMap.get(loader);
164
165 if (providers != null)
166 return providers;
167
168 ArrayList <Class > list = new ArrayList <Class >();
169
170 try {
171 Enumeration e = loader.getResources(service);
172
173 while (e.hasMoreElements()) {
174 URL url = (URL ) e.nextElement();
175
176 Class provider = loadProvider(url, loader);
177
178 if (provider != null)
179 list.add(provider);
180 }
181 } catch (Throwable e) {
182 log.log(Level.WARNING, e.toString(), e);
183 }
184
185 providers = new Class [list.size()];
186 list.toArray(providers);
187
188 _providerMap.put(loader, providers);
189
190 return providers;
191 }
192
193 private Class loadProvider(URL url, ClassLoader loader)
194 {
195 InputStream is = null;
196 try {
197 is = url.openStream();
198 int ch;
199
200 while ((ch = is.read()) >= 0) {
201 if (Character.isWhitespace((char) ch)) {
202 }
203 else if (ch == '#') {
204 for (; ch >= 0 && ch != '\n' && ch != '\r'; ch = is.read()) {
205 }
206 }
207 else {
208 StringBuilder sb = new StringBuilder ();
209
210 for (;
211 ch >= 0 && ! Character.isWhitespace((char) ch);
212 ch = is.read()) {
213 sb.append((char) ch);
214 }
215
216 String className = sb.toString();
217
218 Class cl = Class.forName(className, false, loader);
219
220 return cl;
221 }
222 }
223 } catch (Exception e) {
224 log.log(Level.WARNING, e.toString(), e);
225 } finally {
226 try {
227 if (is != null)
228 is.close();
229 } catch (IOException e) {
230 }
231 }
232
233 return null;
234 }
235 }
236
237
238 |
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