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1
25
26 package net.yagga.util;
27
28 import java.net.URL  ;
29 import java.net.URLClassLoader ;
30 import java.net.JarURLConnection ;
31 import java.lang.reflect.Method ;
32 import java.lang.reflect.Modifier ;
33 import java.lang.reflect.InvocationTargetException ;
34 import java.util.jar.Attributes ;
35 import java.io.IOException ;
36 import java.util.jar.*;
38 import java.util.*;
39 import java.io.*;
40
43 class JarClassLoader extends ClassLoader
44 {
45 private String jarFile;
46 private Hashtable htSizes=new Hashtable();
47
48 public JarClassLoader(String jarF) {
49 super();
50 this.jarFile = jarF;
51 }
52
53
57 public String getMainClassName() throws IOException
58 {
59 JarFile jf=new JarFile(jarFile);
60 Manifest mf = jf.getManifest();
61 return mf != null ? mf.getMainAttributes().getValue(Attributes.Name.MAIN_CLASS) : null;
62 }
63
64
70 public void invokeClass(String name, String [] args)
71 throws ClassNotFoundException ,
72 NoSuchMethodException ,
73 InvocationTargetException
74 {
75 Class c = loadClass(name);
76
77 Method m = c.getMethod("main", new Class [] { args.getClass() });
79 m.setAccessible(true);
81 int mods = m.getModifiers();
82 if (m.getReturnType() != void.class || !Modifier.isStatic(mods) ||
83 !Modifier.isPublic(mods)) {
84 throw new NoSuchMethodException ("main");
85 }
86 try {
87 m.invoke(null, new Object [] { args });
88 } catch (IllegalAccessException e) {
89 }
91 }
92
93
94 protected Class findClass(String className) throws ClassNotFoundException
95 {
96 String urlName=className.replace('.', '/') + ".class";
97 Ut.infoln("findClass1 :"+className);
98 byte[] b1=getClassFromJar(urlName);
99 try{
100 return defineClass(className,b1,0,b1.length);
101 }catch(ClassFormatError cfe){
102 Ut.error("'"+className+"':"+cfe);
103 }
104 return null;
105 }
106
107 private void initSizes()
108 {
109 try{
110 JarFile zf=new JarFile(jarFile);
111 Enumeration e=zf.entries();
112 while (e.hasMoreElements())
113 {
114 JarEntry ze=(JarEntry)e.nextElement();
115 htSizes.put(ze.getName(),new Integer ((int)ze.getSize()));
116 }
117 zf.close();
118 }
119 catch(IOException ioe){
120 Ut.error("Error reading sizes in '"+jarFile+"':"+ioe);
121 }
122 }
123
124 public byte[] getClassFromJar(String cl)
125 {
126 initSizes();
127 try
128 {
129 JarInputStream zis=getJIS(jarFile);
131 JarEntry ze=null;
132 while ((ze=zis.getNextJarEntry())!=null)
133 {
134 if (ze.isDirectory())
135 continue;
136
137 int size=(int)ze.getSize();
138 if (size==-1)
139 size=((Integer )htSizes.get(ze.getName())).intValue();
140
141 if(ze.getName().equals(cl))
142 {
143 byte[] b=new byte[(int)size];
144 int rb=0;
145 int chunk=0;
146 while (((int)size - rb) > 0)
147 {
148 chunk=zis.read(b,rb,(int)size - rb);
149 if (chunk==-1)
150 break;
151 rb+=chunk;
152 }
153 return b;
154 }
155 }
156 }
157 catch (NullPointerException e) {
158 Ut.error("'"+jarFile+"':(done)"+e);
159 } catch (FileNotFoundException e) {
160 Ut.error("'"+jarFile+"':"+e);
161 } catch (IOException e) {
162 Ut.error("'"+jarFile+"':"+e);
163 }
164 return null;
165 }
166
167
168 private JarInputStream getJIS(String jarFile)
169 {
170 try{
171 InputStream is=ResourceMgr.openResource(jarFile);
172 return new JarInputStream(is);
173 }catch(IOException io){
174 Ut.error("IOE..."+io);
175 }
176 return null;
177 }
178
179 private InputStream openResource(String filename)
180 {
181 try
182 {
183 InputStream is=ResourceMgr.class.getResourceAsStream("/"+filename);
184 is.available(); return is;
186 }
187 catch (java.io.IOException e)
188 {
189 Ut.error("RM2: file not found:"+filename);
190 System.exit(1);
191 }
192 catch(NullPointerException e2){
193 Ut.error("RM2: file not found!"+filename);
194 System.exit(1);
195 }
196 return null;
197 }
198
199 }
200
201
204
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