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1 package org.sapia.util.xml.confix;
2
3
4 import org.sapia.util.CompositeRuntimeException;
7
8 import java.io.BufferedReader  ;
11 import java.io.File ;
12 import java.io.FileInputStream ;
13 import java.io.IOException ;
14 import java.io.InputStream ;
15 import java.io.InputStreamReader ;
16 import java.io.UnsupportedEncodingException ;
17
18 import java.lang.reflect.Constructor ;
19
20 import java.util.Properties ;
21
22
23
47 public class ConfixProcessorFactory {
48
52
53 public static final String PROCESSOR_CLASS_PROPERTY = "org.sapia.xml.ConfixProcessor";
54
55
56 public static final String PROCESSOR_CLASS_FILENAME = "sapia.properties";
57
58
59 public static final String PROCESSOR_CLASS_RESOURCE = "META-INF/services/" +
60 PROCESSOR_CLASS_PROPERTY;
61
62
63 public static final String DEFAULT_PROCESSOR_CLASS = "org.sapia.util.xml.confix.SAXProcessor";
64
65
69
70 private Class _theProcessorClass;
71
72
76
79 protected ConfixProcessorFactory(Class aClass) {
80 _theProcessorClass = aClass;
81 }
82
83
87
92 public static ConfixProcessorFactory newFactory() {
93 Class aProcessorClass = retrieveClassFromSystemProperties();
94
95 if (aProcessorClass == null) {
96 aProcessorClass = retrieveClassFromJavaHome();
97
98 if (aProcessorClass == null) {
99 aProcessorClass = retrieveClassFromResource();
100
101 if (aProcessorClass == null) {
102 aProcessorClass = loadClassFromName(DEFAULT_PROCESSOR_CLASS);
103 }
104 }
105 }
106
107 return new ConfixProcessorFactory(aProcessorClass);
108 }
109
110
118 private static Class retrieveClassFromSystemProperties() {
119 String aClassName = System.getProperty(PROCESSOR_CLASS_PROPERTY);
120
121 return loadClassFromName(aClassName);
122 }
123
124
132 private static Class retrieveClassFromJavaHome() {
133 StringBuffer aFileName = new StringBuffer (System.getProperty("java.home"));
134 aFileName.append(File.separator).append("lib").append(File.separator)
135 .append(PROCESSOR_CLASS_FILENAME);
136
137 File aFile = new File (aFileName.toString());
138
139 if (aFile.exists()) {
140 FileInputStream anInput = null;
141
142 try {
143 Properties someProperties = new Properties ();
144 anInput = new FileInputStream (aFile);
145 someProperties.load(anInput);
146
147 String aClassName = someProperties.getProperty(PROCESSOR_CLASS_PROPERTY);
148
149 return loadClassFromName(aClassName);
150 } catch (IOException ioe) {
151 StringBuffer aBuffer = new StringBuffer ();
152 aBuffer.append(
153 "ConfixProcessorFactory: WARNING unable to read the file ").append(aFileName.toString());
154 System.out.println(aBuffer.toString());
155
156 return null;
157 } finally {
158 if (anInput != null) {
159 try {
160 anInput.close();
161 } catch (IOException ioe) {
162 }
163 }
164 }
165 } else {
166 return null;
167 }
168 }
169
170
173 private static Class retrieveClassFromResource() {
174 InputStream anInput = null;
175 BufferedReader aReader = null;
176
177 try {
178 anInput = Thread.currentThread().getContextClassLoader()
179 .getResourceAsStream(PROCESSOR_CLASS_RESOURCE);
180
181 if (anInput != null) {
182 try {
183 aReader = new BufferedReader (new InputStreamReader (anInput, "UTF-8"));
184 } catch (UnsupportedEncodingException uee) {
185 aReader = new BufferedReader (new InputStreamReader (anInput));
186 }
187
188 String aClassName = aReader.readLine();
189
190 return loadClassFromName(aClassName);
191 } else {
192 return null;
193 }
194 } catch (IOException ioe) {
195 StringBuffer aBuffer = new StringBuffer ();
196 aBuffer.append(
197 "ConfixProcessorFactory: WARNING unable to read the resource ").append(PROCESSOR_CLASS_RESOURCE);
198 System.out.println(aBuffer.toString());
199
200 return null;
201 } finally {
202 if (aReader != null) {
203 try {
204 aReader.close();
205 } catch (IOException ioe) {
206 }
207 }
208
209 if (anInput != null) {
210 try {
211 anInput.close();
212 } catch (IOException ioe) {
213 }
214 }
215 }
216 }
217
218
226 private static Class loadClassFromName(String aClassName) {
227 if ((aClassName != null) && (aClassName.length() > 0)) {
228 try {
229 Class aClass = Thread.currentThread().getContextClassLoader().loadClass(aClassName);
230
231 if (ConfixProcessorIF.class.isAssignableFrom(aClass)) {
232 return aClass;
233 } else {
234 StringBuffer aBuffer = new StringBuffer ();
235 aBuffer.append("ConfixProcessorFactory: WARNING found the class ")
236 .append(aClassName).append(" but it is not a ConfixProcessorIF");
237 System.out.println(aBuffer.toString());
238
239 return null;
240 }
241 } catch (ClassNotFoundException cnfe) {
242 StringBuffer aBuffer = new StringBuffer ();
243 aBuffer.append(
244 "ConfixProcessorFactory: WARNING unable to load the class name ")
245 .append(aClassName);
246 System.out.println(aBuffer.toString());
247
248 return null;
249 }
250 } else {
251 return null;
252 }
253 }
254
255
259
264 public ConfixProcessorIF createProcessor(ObjectFactoryIF aFactory) {
265 try {
266 Constructor aConstructor = _theProcessorClass.getConstructor(new Class [] {
267 ObjectFactoryIF.class
268 });
269
270 return (ConfixProcessorIF) aConstructor.newInstance(new Object [] { aFactory });
271 } catch (Exception e) {
272 throw new CompositeRuntimeException("Unable to create a Confix processor",
273 e);
274 }
275 }
276 }
277 |
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