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1
21 package com.jaspersoft.jasperserver.api.engine.jasperreports.util;
22
23 import java.io.IOException  ;
24 import java.net.URL ;
25 import java.util.Enumeration ;
26 import java.util.Vector ;
27 import java.util.jar.JarEntry ;
28 import java.util.jar.JarFile ;
29
30 import org.apache.commons.logging.Log;
31 import org.apache.commons.logging.LogFactory;
32
33 import com.jaspersoft.jasperserver.api.metadata.common.domain.util.StreamUtils;
34
35
39 public class JarsClassLoader extends ClassLoader {
40 private static final Log log = LogFactory.getLog(JarsClassLoader.class);
41
42 private final JarURLStreamHandler urlStreamHandler;
43
44 private final JarFile [] jars;
45
46 public JarsClassLoader(JarFile [] jars, ClassLoader parent) {
47 super(parent);
48
49 this.urlStreamHandler = new JarURLStreamHandler();
50 this.jars = jars;
51 }
52
53 protected Class findClass(String name) throws ClassNotFoundException {
54 String path = name.replace('.', '/').concat(".class");
55
56 JarFileEntry entry = findPath(path);
57
58 if (entry == null) {
59 throw new ClassNotFoundException (name);
60 }
61
62
64 byte[] classData;
65 try {
66 long size = entry.getSize();
67 if (size >= 0) {
68 classData = StreamUtils.readData(entry.getInputStream(),
69 (int) size);
70 } else {
71 classData = StreamUtils.readData(entry.getInputStream());
72 }
73 } catch (IOException e) {
74 log.debug(e, e);
75 throw new ClassNotFoundException (name, e);
76 }
77
78 return defineClass(name, classData, 0, classData.length,
79 JarsClassLoader.class.getProtectionDomain());
80 }
81
82 protected JarFileEntry findPath(String path) {
83 JarFileEntry entry = null;
84 for (int i = 0; i < jars.length && entry == null; i++) {
85 entry = getJarEntry(jars[i], path);
86 }
87 return entry;
88 }
89
90 protected URL findResource(String name) {
91 JarFileEntry entry = findPath(name);
92 return entry == null ? null : urlStreamHandler.createURL(entry);
93 }
94
95 protected Enumeration findResources(String name) throws IOException {
96 Vector urls = new Vector ();
97 for (int i = 0; i < jars.length; i++) {
98 JarFileEntry entry = getJarEntry(jars[i], name);
99 if (entry != null) {
100 urls.add(urlStreamHandler.createURL(entry));
101 }
102 }
103 return urls.elements();
104 }
105
106 protected static JarFileEntry getJarEntry(JarFile jar, String name) {
107 if (name.startsWith("/")) {
108 name = name.substring(1);
109 }
110
111 JarFileEntry jarEntry = null;
112 JarEntry entry = jar.getJarEntry(name);
113 if (entry != null) {
114 jarEntry = new JarFileEntry(jar, entry);
115 }
116
117 return jarEntry;
118 }
119 }
120 |
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