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1
30
31 package org.theshoemakers.which4j;
32
33 import java.io.File  ;
34 import java.net.URL ;
35 import java.net.URLClassLoader ;
36 import java.util.Properties ;
37 import java.util.StringTokenizer ;
38
39
54 public class Which4J {
55
56 private static boolean debug = false;
57
58
65 public static void main(String [] args) {
66 String s = System.getProperty("line.separator");
67 if (args.length == 2) {
68 if (args[0].equals("-debug")) {
69 debug = true;
70 findIt(args[1]);
71 } else {
72 System.err.println(
73 "error: unrecognized \"" + args[0] + "\" option ");
74 System.exit(-1);
75 }
76 } else if (args.length == 1 && args[0].equals("-help")) {
77 usage();
78 } else if (args.length == 1) {
79 findIt(args[0]);
80 } else {
81 usage();
82 }
83
84 System.exit(0);
85 }
86
87 private static void usage() {
88 System.err.println(
89 "usage: java Which4J [-debug] <classname>"
90 + "\n\tThe commandline version of Which4J will search the system"
91 + "\n\tclasspath defined in your environment for all occurences"
92 + "\n\tof the class. Alternatively, you can use this class"
93 + "\n\tprogrammatically to search the current (or any) ClassLoader."
94 + "\n\tSee the javadoc for more detail."
95 + "\n\t"
96 + "\n\tNote: if the name of the jar file listed after \"found in:\""
97 + "\n\tdoesn't match the name of the jar listed next to \"url:\", then "
98 + "\n\tthere is likely a \"Class-Path\" entry in the jar manifest "
99 + "\n\tthat is causing the classloader to indirectly find the class.");
100 System.exit(-1);
101 }
102
103
109 private static void findIt(String classname) {
110
111 try {
112 String classpath = System.getProperty("java.class.path", "");
114
115 if (classpath.equals("")) {
116 System.err.println("error: classpath is not set");
117 }
118
119 if (debug) {
120 System.out.println("classname: " + classname);
121 System.out.println("system classpath = " + classpath);
122 }
123
124 if (isPrimitiveOrVoid(classname)) {
125 System.out.println("'" + classname + "' primitive");
126 return;
127 }
128
129 StringTokenizer st =
130 new StringTokenizer (classpath, File.pathSeparator);
131
132 String classnameAsResource = classname.replace('.', '/') + ".class";
133 boolean checkSystemClassLoader = true;
134
135 while (st.hasMoreTokens()) {
136 String token = st.nextToken();
137 File classpathElement = new File (token);
138
139 if (debug)
140 System.out.println(
141 classpathElement.isDirectory()
142 ? "dir: " + token
143 : "jar: " + token);
144
145 URL [] url = { classpathElement.toURL()};
146
147 URLClassLoader cl = URLClassLoader.newInstance(url, null);
148
149 URL it = cl.findResource(classnameAsResource);
150 if (it != null) {
151 checkSystemClassLoader = false;
152 System.out.println("found in: " + token);
153 System.out.println(" url: " + it.toString());
154 System.out.println("");
155 }
156 }
157
158 if (checkSystemClassLoader) {
159 URL it = ClassLoader.getSystemResource(classnameAsResource);
160 if (it != null) {
161 checkSystemClassLoader = false;
162 System.out.println("found in url: " + it.toString());
163 System.out.println("");
164 }
165 }
166 } catch (Exception e) {
167 e.printStackTrace();
168 }
169 }
170
171
179 public static String which(String classname) {
180 return which(classname, Which4J.class.getClassLoader());
181 }
182
183
190 public static String which(String classname, ClassLoader loader) {
191
192 if (isArrayType(classname)) {
193 classname = getElementType(classname);
194 }
195
196 if (isPrimitiveOrVoid(classname)) {
197 return "'" + classname + "' primitive";
198 }
199
200 String classnameAsResource = classname.replace('.', '/') + ".class";
201
202 if (loader == null) {
203 loader = ClassLoader.getSystemClassLoader();
206 }
207 URL it = loader.getResource(classnameAsResource);
208 if (it != null) {
209 return it.toString();
210 } else {
211 return null;
212 }
213 }
214
215
223 public static String which(Class clazz) {
224 return which(clazz, clazz.getClassLoader());
225 }
226
227
234 public static String which(Class clazz, ClassLoader loader) {
235 return which(clazz.getName(), loader);
236 }
237
238
246 private static boolean isPrimitiveOrVoid(String classname) {
247 return (
248 classname.equals("boolean")
249 || classname.equals("byte")
250 || classname.equals("char")
251 || classname.equals("double")
252 || classname.equals("float")
253 || classname.equals("int")
254 || classname.equals("long")
255 || classname.equals("short")
256 || classname.equals("void"));
257 }
258
259
267 private static boolean isArrayType(String classname) {
268 return classname.startsWith("[");
269 }
270
271
279 private static String getElementType(String classname) {
280 String elementType = classname.split("^\\[+")[1];
282 char encoding = elementType.charAt(0);
283
284 if (encoding == 'L') {
285 return elementType.substring(1, elementType.length() - 1);
287 } else if (encoding == 'Z') {
288 return "boolean";
289 } else if (encoding == 'B') {
290 return "byte";
291 } else if (encoding == 'C') {
292 return "char";
293 } else if (encoding == 'D') {
294 return "double";
295 } else if (encoding == 'F') {
296 return "float";
297 } else if (encoding == 'I') {
298 return "int";
299 } else if (encoding == 'J') {
300 return "long";
301 } else if (encoding == 'S') {
302 return "short";
303 } else {
304 throw new InternalError (
305 "unknown array type: '"
306 + encoding
307 + "'.\nplease file a bug report at http://which4j.dev.java.net");
308 }
309 }
310
311 }
312 |
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