1 cananian 1.10.2.8 // Loader.java, created Fri Jul 31 4:33:28 1998 by cananian
2 cananian 1.5 // Copyright (C) 1998 C. Scott Ananian <cananian@alumni.princeton.edu>
3 cananian 1.5 // Licensed under the terms of the GNU GPL; see COPYING for details.
4 cananian 1.1 package harpoon.ClassFile;
5 cananian 1.1
6 cananian 1.1 import java.io.File;
7 cananian 1.1 import java.io.InputStream;
8 cananian 1.1 import java.io.FileInputStream;
9 cananian 1.10.2.13 import java.io.Serializable;
10 cananian 1.10.2.7 import java.util.ArrayList;
11 cananian 1.10.2.7 import java.util.HashSet;
12 cananian 1.10.2.7 import java.util.Iterator;
13 cananian 1.10.2.7 import java.util.List;
14 cananian 1.10.2.7 import java.util.Set;
15 cananian 1.1 import java.util.zip.ZipFile;
16 cananian 1.1 import java.util.zip.ZipEntry;
17 cananian 1.1
18 cananian 1.10.2.13 import java.io.BufferedInputStream;
19 cananian 1.1 import java.io.IOException;
20 cananian 1.1 import java.io.FileNotFoundException;
21 cananian 1.1
22 cananian 1.10.2.11 import harpoon.Util.ArrayIterator;
23 cananian 1.16 import net.cscott.jutil.CombineIterator;
24 cananian 1.16 import net.cscott.jutil.Default;
25 cananian 1.10.2.11 import harpoon.Util.EnumerationIterator;
26 cananian 1.16 import net.cscott.jutil.FilterIterator;
27 cananian 1.10.2.2 import harpoon.Util.Util;
28 cananian 1.15
29 cananian 1.16 import net.cscott.jutil.UnmodifiableIterator;
30 cananian 1.15
31 cananian 1.6 /**
32 cananian 1.10.2.3 * Class file loader.
33 cananian 1.10.2.3 * Looks through CLASSPATH to find resources. Understands .jar and .zip
34 cananian 1.10.2.3 * files. Platform-independent (hopefully).
35 cananian 1.2 *
36 cananian 1.6 * @author C. Scott Ananian <cananian@alumni.princeton.edu>
37 cananian 1.17 * @version $Id: Loader.java,v 1.17 2004/02/08 03:21:10 cananian Exp $
38 cananian 1.1 */
39 cananian 1.9 public abstract class Loader {
40 cananian 1.10.2.2 static abstract class ClasspathElement {
41 cananian 1.10.2.3 /** Open a stream to read the given resource, or return
42 cananian 1.10.2.3 * <code>null</code> if resource cannot be found. */
43 cananian 1.10.2.2 abstract InputStream getResourceAsStream(String resourcename);
44 cananian 1.10.2.11 /** Iterate over all classes in the given package. */
45 cananian 1.10.2.11 abstract Iterator listPackage(String packagename);
46 cananian 1.10.2.2 }
47 cananian 1.10.2.2 /** A .zip or .jar file in the CLASSPATH. */
48 cananian 1.10.2.2 static class ZipFileElement extends ClasspathElement {
49 cananian 1.10.2.2 ZipFile zf;
50 cananian 1.10.2.2 ZipFileElement(ZipFile zf) { this.zf = zf; }
51 cananian 1.10.2.14 public String toString() { return zf.getName(); }
52 cananian 1.10.2.2 InputStream getResourceAsStream(String name) {
53 cananian 1.10.2.16 name = name.replace('\\','/'); // work around bug in windows java ports
54 cananian 1.10.2.2 try { // look for name in zipfile, return null if something goes wrong.
55 cananian 1.10.2.2 ZipEntry ze = zf.getEntry(name);
56 cananian 1.10.2.2 return (ze==null)?null:zf.getInputStream(ze);
57 cananian 1.10.2.10 } catch (UnsatisfiedLinkError e) {
58 cananian 1.10.2.10 System.err.println("UNSATISFIED LINK ERROR: "+name);
59 cananian 1.10.2.10 return null;
60 cananian 1.10.2.2 } catch (IOException e) { return null; }
61 cananian 1.10.2.2 }
62 cananian 1.10.2.11 Iterator listPackage(final String pathname) {
63 cananian 1.10.2.11 // look for directory name first
64 cananian 1.10.2.11 final String filesep = System.getProperty("file.separator");
65 cananian 1.10.2.11 /* not all .JAR files have entries for directories, unfortunately.
66 cananian 1.10.2.11 ZipEntry ze = zf.getEntry(pathname);
67 cananian 1.10.2.11 if (ze==null) return Default.nullIterator;
68 cananian 1.10.2.11 */
69 cananian 1.10.2.11 return new FilterIterator(new EnumerationIterator(zf.entries()),
70 cananian 1.10.2.11 new FilterIterator.Filter() {
71 cananian 1.10.2.11 public boolean isElement(Object o) { ZipEntry zze=(ZipEntry) o;
72 cananian 1.10.2.11 String name = zze.getName();
73 cananian 1.10.2.11 return (!zze.isDirectory()) && name.startsWith(pathname) &&
74 cananian 1.10.2.11 name.lastIndexOf(filesep)==(pathname.length()-1);
75 cananian 1.10.2.11 }
76 cananian 1.10.2.11 public Object map(Object o) {
77 cananian 1.10.2.11 return ((ZipEntry)o).getName();
78 cananian 1.7 }
79 cananian 1.10.2.11 });
80 cananian 1.10.2.11 }
81 cananian 1.10.2.2 /** Close the zipfile when this object is garbage-collected. */
82 cananian 1.10.2.2 protected void finalize() throws Throwable {
83 cananian 1.10.2.6 // yes, it is possible to finalize an uninitialized object.
84 cananian 1.10.2.6 try { if (zf!=null) zf.close(); } finally { super.finalize(); }
85 cananian 1.10.2.2 }
86 cananian 1.10.2.2 }
87 cananian 1.10.2.2 /** A regular path string in the CLASSPATH. */
88 cananian 1.10.2.2 static class PathElement extends ClasspathElement {
89 cananian 1.10.2.2 String path;
90 cananian 1.10.2.2 PathElement(String path) { this.path = path; }
91 cananian 1.10.2.14 public String toString() { return path; }
92 cananian 1.10.2.2 InputStream getResourceAsStream(String name) {
93 cananian 1.10.2.2 try { // try to open the file, starting from path.
94 cananian 1.10.2.2 File f = new File(path, name);
95 cananian 1.10.2.5 return new FileInputStream(f);
96 cananian 1.10.2.2 } catch (FileNotFoundException e) {
97 cananian 1.10.2.2 return null; // if anything goes wrong, return null.
98 cananian 1.7 }
99 cananian 1.10.2.2 }
100 cananian 1.10.2.11 Iterator listPackage(final String pathname) {
101 cananian 1.10.2.11 File f = new File(path,pathname);
102 cananian 1.10.2.11 if (!f.exists() || !f.isDirectory()) return Default.nullIterator;
103 cananian 1.10.2.11 return new FilterIterator(new ArrayIterator(f.list()),
104 cananian 1.10.2.11 new FilterIterator.Filter() {
105 cananian 1.10.2.11 public Object map(Object o) { return pathname + ((String)o); }
106 cananian 1.10.2.11 });
107 cananian 1.10.2.11 }
108 cananian 1.10.2.2 }
109 cananian 1.10.2.2
110 cananian 1.10.2.2 /** Static vector of ClasspathElements corresponding to CLASSPATH entries. */
111 cananian 1.10.2.7 static final List classpathList = new ArrayList();
112 cananian 1.10.2.2 static { // initialize classpathVector.
113 cananian 1.10.2.7 Set duplicates = new HashSet(); // don't add duplicates.
114 cananian 1.10.2.7 for (Iterator it = classpaths(); it.hasNext(); ) {
115 cananian 1.10.2.7 String path = (String) it.next();
116 cananian 1.10.2.7 if (duplicates.contains(path)) continue; // skip duplicate.
117 cananian 1.10.2.7 else duplicates.add(path);
118 cananian 1.10.2.2 if (path.toLowerCase().endsWith(".zip") ||
119 cananian 1.10.2.2 path.toLowerCase().endsWith(".jar"))
120 cananian 1.10.2.2 try {
121 cananian 1.10.2.7 classpathList.add(new ZipFileElement(new ZipFile(path)));
122 cananian 1.10.2.2 } catch (IOException ex) { /* skip this zip file, then. */ }
123 cananian 1.10.2.2 else
124 cananian 1.10.2.7 classpathList.add(new PathElement(path));
125 cananian 1.10.2.2 }
126 cananian 1.10.2.7 ((ArrayList) classpathList).trimToSize(); // save memory.
127 cananian 1.7 }
128 cananian 1.10.2.2
129 cananian 1.10.2.7 /** Iterate over the components of the system CLASSPATH.
130 cananian 1.10.2.3 * Each element is a <code>String</code> naming one segment of the
131 cananian 1.10.2.3 * CLASSPATH. */
132 cananian 1.10.2.7 public static final Iterator classpaths() {
133 cananian 1.10.2.4 final String pathsep = System.getProperty("path.separator");
134 cananian 1.10.2.9 String classpath = null;
135 cananian 1.10.2.9
136 cananian 1.10.2.9 // allow overriding classpath.
137 cananian 1.10.2.9 /*if (classpath==null) classpath = System.getenv("HCLASSPATH");*/
138 cananian 1.10.2.9 if (classpath==null) classpath = System.getProperty("harpoon.class.path");
139 cananian 1.10.2.9 if (classpath==null) classpath = System.getProperty("java.class.path");
140 cananian 1.13.2.1 assert classpath!=null;
141 cananian 1.7
142 cananian 1.7 // For convenience, make sure classpath begins with and ends with pathsep.
143 cananian 1.7 if (!classpath.startsWith(pathsep)) classpath = pathsep + classpath;
144 cananian 1.7 if (!classpath.endsWith(pathsep)) classpath = classpath + pathsep;
145 cananian 1.7 final String cp = classpath;
146 cananian 1.7
147 cananian 1.10.2.7 return new UnmodifiableIterator() {
148 cananian 1.7 int i=0;
149 cananian 1.10.2.7 public boolean hasNext() {
150 cananian 1.7 return (cp.length() > (i+pathsep.length()));
151 cananian 1.7 }
152 cananian 1.10.2.7 public Object next() {
153 cananian 1.7 i+=pathsep.length(); // cp begins with pathsep.
154 cananian 1.7 String path = cp.substring(i, cp.indexOf(pathsep, i));
155 cananian 1.7 i+=path.length(); // skip over path.
156 cananian 1.7 return path;
157 cananian 1.7 }
158 cananian 1.7 };
159 cananian 1.7 }
160 cananian 1.7
161 cananian 1.10.2.3 /** Translate a class name into a corresponding resource name.
162 cananian 1.10.2.3 * @param classname The class name to translate.
163 cananian 1.10.2.3 */
164 cananian 1.1 public static String classToResource(String classname) {
165 cananian 1.13.2.1 assert classname.indexOf('/')==-1; // should have '.' separators.
166 cananian 1.1 String filesep = System.getProperty("file.separator");
167 cananian 1.1 // Swap all '.' for '/' & append ".class"
168 cananian 1.1 return classname.replace('.', filesep.charAt(0)) + ".class";
169 cananian 1.1 }
170 cananian 1.1
171 cananian 1.10.2.3 /** Open an <code>InputStream</code> on a resource found somewhere
172 cananian 1.10.2.3 * in the CLASSPATH.
173 cananian 1.1 * @param name The filename of the resource to locate.
174 cananian 1.1 */
175 cananian 1.1 public static InputStream getResourceAsStream(String name) {
176 cananian 1.17 for (Object cpeO : classpathList) {
177 cananian 1.17 ClasspathElement cpe = (ClasspathElement) cpeO;
178 cananian 1.10.2.2 InputStream is = cpe.getResourceAsStream(name);
179 cananian 1.10.2.14 if (is!=null) {
180 cananian 1.10.2.14 //System.err.println("[LOADING "+new File(cpe.toString(),name)+"]");
181 cananian 1.10.2.14 return is; // return stream if found.
182 cananian 1.10.2.14 }
183 cananian 1.1 }
184 cananian 1.1 // Couldn't find resource.
185 cananian 1.1 return null;
186 cananian 1.1 }
187 cananian 1.1
188 cananian 1.10.2.11 /** Returns an iterator of Strings naming the available classes in
189 cananian 1.10.2.11 * the given package which are on the classpath. */
190 cananian 1.10.2.11 public static Iterator listClasses(String packagename) {
191 cananian 1.10.2.11 final String filesep = System.getProperty("file.separator");
192 cananian 1.10.2.12 final String pathname = (packagename.length()==0)?"":
193 cananian 1.10.2.12 (packagename.replace('.',filesep.charAt(0))+filesep);
194 cananian 1.10.2.11 FilterIterator.Filter cpe2sl = new FilterIterator.Filter() {
195 cananian 1.10.2.11 public Object map(Object o) {
196 cananian 1.10.2.12 return ((ClasspathElement) o).listPackage(pathname);
197 cananian 1.10.2.11 }
198 cananian 1.10.2.11 };
199 cananian 1.10.2.11 FilterIterator.Filter sl2cl = new FilterIterator.Filter() {
200 cananian 1.10.2.11 private Set nodups = new HashSet();
201 cananian 1.10.2.11 public boolean isElement(Object o) {
202 cananian 1.10.2.11 return ((String)o).toLowerCase().endsWith(".class") &&
203 cananian 1.10.2.11 !nodups.contains(o);
204 cananian 1.10.2.11 }
205 cananian 1.10.2.11 public Object map(Object o) {
206 cananian 1.10.2.11 String name = (String) o; nodups.add(o);
207 cananian 1.10.2.11 return name.substring(0,name.length()-6)
208 cananian 1.10.2.11 .replace(filesep.charAt(0),'.');
209 cananian 1.1 }
210 cananian 1.10.2.11 };
211 cananian 1.10.2.11 return new FilterIterator(new CombineIterator(
212 cananian 1.10.2.11 new FilterIterator(classpathList.iterator(), cpe2sl)), sl2cl);
213 cananian 1.1 }
214 cananian 1.1
215 cananian 1.10.2.13 /** System-linker: the class names resolved by this linker are always
216 cananian 1.10.2.13 * immutable and identical to those on disk.
217 cananian 1.10.2.13 */
218 cananian 1.10.2.13 public static final Linker systemLinker = new SystemLinker();
219 cananian 1.10.2.13 private static class SystemLinker extends Linker implements Serializable {
220 cananian 1.10.2.13 protected final HClass forDescriptor0(String descriptor)
221 cananian 1.10.2.13 throws NoSuchClassException {
222 cananian 1.13.2.1 assert descriptor.startsWith("L") && descriptor.endsWith(";");
223 cananian 1.10.2.13 // classname in descriptor is '/' delimited.
224 cananian 1.10.2.13 String className = descriptor.substring(1, descriptor.indexOf(';'));
225 cananian 1.10.2.13 className = className.replace('/','.'); // make proper class name.
226 cananian 1.10.2.13 InputStream is =
227 cananian 1.10.2.13 Loader.getResourceAsStream(Loader.classToResource(className));
228 cananian 1.10.2.13 if (is == null) throw new NoSuchClassException(className);
229 cananian 1.10.2.13 // OK, go ahead and load this.
230 cananian 1.10.2.13 try {
231 cananian 1.10.2.13 return /*ImplGNU*/ImplMagic.forStream(this, new BufferedInputStream(is));
232 cananian 1.10.2.13 } catch (java.lang.ClassFormatError e) {
233 cananian 1.10.2.13 throw new NoSuchClassException(className+" ["+e.toString()+"]");
234 cananian 1.10.2.13 } catch (java.io.IOException e) {
235 cananian 1.10.2.13 throw new NoSuchClassException(className);
236 cananian 1.10.2.13 } finally {
237 cananian 1.10.2.13 try { is.close(); } catch(java.io.IOException e) { }
238 cananian 1.10.2.13 }
239 cananian 1.10.2.13 }
240 cananian 1.10.2.13 /* Serializable interface: system linker is unique. */
241 cananian 1.10.2.13 public Object writeReplace() { return new Stub(); }
242 cananian 1.10.2.13 private static final class Stub implements Serializable {
243 cananian 1.10.2.15 public Object readResolve() {
244 cananian 1.10.2.15 return Loader.replaceWithRelinker ?
245 cananian 1.10.2.15 Loader.systemRelinker : Loader.systemLinker;
246 cananian 1.10.2.15 }
247 cananian 1.1 }
248 cananian 1.1 }
249 cananian 1.10.2.15 // allow the user to reserialize a systemLinker (and associated classes)
250 cananian 1.10.2.15 // as a *relinker*... evil evil evil evil. [CSA 4-apr-2000]
251 cananian 1.10.2.15 final static boolean replaceWithRelinker =
252 cananian 1.10.2.15 System.getProperty("harpoon.relinker.hack", "no")
253 cananian 1.10.2.15 .equalsIgnoreCase("yes");
254 cananian 1.10.2.15 final static Linker systemRelinker = new Relinker(systemLinker);
255 cananian 1.10.2.15
256 cananian 1.10.2.13 /** System code factory: this code factory will return bytecode
257 cananian 1.10.2.13 * representations for classes loaded via the system linker. */
258 cananian 1.10.2.13 public static final HCodeFactory systemCodeFactory =
259 cananian 1.10.2.13 /*ImplGNU*/ImplMagic.codeFactory;
260 cananian 1.1 }
261 cananian 1.10.2.2 // set emacs indentation style.
262 cananian 1.10.2.2 // Local Variables:
263 cananian 1.10.2.2 // c-basic-offset:2
264 cananian 1.12 // End: