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1
23
24 package org.objectweb.fractal.julia.loader;
25
26 import org.objectweb.fractal.julia.asm.ClassGenerationException;
27 import org.objectweb.fractal.julia.asm.ClassGenerator;
28
29 import java.io.BufferedOutputStream  ;
30 import java.io.ByteArrayInputStream ;
31 import java.io.File ;
32 import java.io.FileOutputStream ;
33 import java.io.FileWriter ;
34 import java.io.InputStream ;
35 import java.util.HashMap ;
36 import java.util.Map ;
37
38
49
50 public class DynamicLoader extends BasicLoader {
51
52
56 public DynamicLoader () {
57 }
58
59
63 private String genLog;
64
65 private String genDir;
66
67 public void init (final Map context) throws Exception {
68 super.init(context);
69
70 if (context.get("julia.loader.gen.dir") != null) {
71 genDir = (String )context.get("julia.loader.gen.dir");
72 } else if (System.getProperty("julia.loader.gen.dir") != null) {
73 genDir = System.getProperty("julia.loader.gen.dir");
74 }
75
76 if (context.get("julia.loader.gen.log") != null) {
77 genLog = (String )context.get("julia.loader.gen.log");
78 } else if (System.getProperty("julia.loader.gen.log") != null) {
79 genLog = System.getProperty("julia.loader.gen.log");
80 }
81 }
82
83 public Class loadClass (final String name, final Object loader)
84 throws ClassNotFoundException
85 {
86 return PublicClassLoader.getInstance(getClassLoader(loader)).loadClass(name);
87 }
88
89 protected Class generateClass (
90 final String name,
91 final Tree classDescriptor,
92 final Object loader) throws ClassNotFoundException
93 {
94 ClassLoader cl = getClassLoader(loader);
95 ClassGenerator classGen = null;
96 try {
97 classGen = (ClassGenerator)newObject(classDescriptor.getSubTree(0), loader);
98 } catch (ClassCastException e) {
99 throw new ClassGenerationException(
100 null,
101 classDescriptor.toString(),
102 "The class generator is not an instance of ClassGenerator");
103 } catch (Exception e) {
104 throw new ClassGenerationException(
105 e, classDescriptor.toString(), "Cannot create the class generator");
106 }
107 byte[] b = classGen.generateClass(name, classDescriptor, this, cl);
108 if (genLog != null) {
109 String line = classDescriptor.toString();
110 if (genLog.equals("out")) {
111 System.out.println(line);
112 } else if (genLog.equals("err")) {
113 System.err.println(line);
114 } else {
115 try {
116 FileWriter fw = new FileWriter (genLog, true);
117 fw.write(line);
118 fw.write('\n');
119 fw.close();
120 } catch (Exception e) {
121 e.printStackTrace();
122 }
123 }
124 }
125 if (genDir != null) {
126 try {
127 String pkg;
128 String cls;
129 int dot = name.lastIndexOf('.');
130 if (dot > 0) {
131 pkg = name.substring(0, dot).replace('.', File.separatorChar);
132 cls = name.substring(dot + 1);
133 } else {
134 pkg = "";
135 cls = name;
136 }
137 File dirFile = new File (new File (genDir), pkg);
138 if (!dirFile.exists()) {
139 dirFile.mkdirs();
140 }
141 File classFile = new File (dirFile, cls + ".class");
142 BufferedOutputStream bos =
143 new BufferedOutputStream (new FileOutputStream (classFile));
144 bos.write(b);
145 bos.close();
146 } catch (Exception e) {
147 e.printStackTrace();
148 }
149 }
150 return PublicClassLoader.getInstance(cl).defineClass(name, b);
151 }
152
153 private ClassLoader getClassLoader (final Object loader) {
154 if (loader instanceof ClassLoader ) {
155 return (ClassLoader )loader;
156 } else if (loader != null) {
157 return loader.getClass().getClassLoader();
158 } else {
159 return getClass().getClassLoader();
160 }
161 }
162
163
167
168 static class PublicClassLoader extends ClassLoader {
169
170
173
174 private final static Map INSTANCES = new HashMap ();
175
176
179
180 private Map bytecodes = new HashMap ();
181
182
188
189 private PublicClassLoader (final ClassLoader parent) {
190 super(parent);
191 }
192
193
201
202 public static PublicClassLoader getInstance (final ClassLoader parent) {
203 synchronized (INSTANCES) {
204 PublicClassLoader instance = (PublicClassLoader)INSTANCES.get(parent);
205 if (instance == null) {
206 instance = new PublicClassLoader(parent);
207 INSTANCES.put(parent, instance);
208 }
209 return instance;
210 }
211 }
212
213
220
221 public Class defineClass (final String name, final byte[] b) {
222 bytecodes.put(name.replace('.', '/') + ".class", b);
223 return defineClass(name, b, 0, b.length);
224 }
225
226 public InputStream getResourceAsStream (final String name) {
227 InputStream is = super.getResourceAsStream(name);
228 if (is == null) {
229 byte[] b = (byte[])bytecodes.get(name);
230 if (b != null) {
231 is = new ByteArrayInputStream (b);
232 }
233 }
234 return is;
235 }
236 }
237 }
238 |
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