1 cananian 1.1.4.1 // Relinker.java, created Mon Dec 27 19:05:58 1999 by cananian
2 cananian 1.1.4.1 // Copyright (C) 1999 C. Scott Ananian <cananian@alumni.princeton.edu>
3 cananian 1.1.4.1 // Licensed under the terms of the GNU GPL; see COPYING for details.
4 cananian 1.1.4.1 package harpoon.ClassFile;
5 cananian 1.1.4.1
6 cananian 1.1.4.8 import java.util.ArrayList;
7 cananian 1.1.4.1 import java.util.HashMap;
8 cananian 1.1.4.8 import java.util.Iterator;
9 cananian 1.1.4.8 import java.util.List;
10 cananian 1.1.4.1 import java.util.Map;
11 cananian 1.5
12 cananian 1.5 import net.cscott.jutil.Util;
13 cananian 1.1.4.1 /**
14 cananian 1.1.4.1 * A <code>Relinker</code> object is a <code>Linker</code> where one
15 cananian 1.1.4.1 * can globally replace references to a certain class with references
16 cananian 1.1.4.1 * to another, different, class.
17 cananian 1.1.4.1 *
18 cananian 1.1.4.1 * @author C. Scott Ananian <cananian@alumni.princeton.edu>
19 cananian 1.6 * @version $Id: Relinker.java,v 1.6 2004/02/08 05:09:46 cananian Exp $
20 cananian 1.1.4.1 */
21 cananian 1.1.4.2 public class Relinker extends Linker implements java.io.Serializable {
22 cananian 1.1.4.1 protected final Linker linker;
23 cananian 1.1.4.1
24 cananian 1.1.4.1 /** Creates a <code>Relinker</code>. */
25 cananian 1.1.4.1 public Relinker(Linker linker) {
26 cananian 1.1.4.1 this.linker = linker;
27 cananian 1.1.4.1 }
28 cananian 1.1.4.1 protected HClass forDescriptor0(String descriptor) {
29 cananian 1.1.4.1 return new HClassProxy(this, linker.forDescriptor(descriptor));
30 cananian 1.1.4.5 }
31 cananian 1.1.4.5 protected HClass makeArray(HClass baseType, int dims) {
32 cananian 1.1.4.10 // two cases: 1) base type's proxy is a mutable class generated
33 cananian 1.1.4.10 // by this relinker, 2) base type's proxy is from linker.
34 cananian 1.1.4.10 // proxy base array type in case 2; create our own HClassArray
35 cananian 1.1.4.10 // for case 1.
36 cananian 1.1.4.10 if (!baseType.isPrimitive()) {
37 cananian 1.1.4.10 HClass baseProxy = ((HClassProxy)baseType).proxy;
38 cananian 1.1.4.10 if (baseProxy.getLinker()==this) // must be our mutable.
39 cananian 1.1.4.10 return new HClassProxy
40 cananian 1.1.4.10 (this, new HClassArray(this, baseProxy, dims));
41 cananian 1.1.4.10 }
42 cananian 1.1.4.10 // otherwise, proxy the linker's array.
43 cananian 1.1.4.6 String desc = Util.repeatString("[",dims) + baseType.getDescriptor();
44 cananian 1.1.4.6 return new HClassProxy(this, linker.forDescriptor(desc));
45 cananian 1.1.4.1 }
46 cananian 1.1.4.1
47 cananian 1.1.4.1 /** Creates a mutable class with the given name which is based on
48 cananian 1.1.4.1 * the given template class. The name <b>need not</b> be unique.
49 cananian 1.1.4.1 * If a class with the given name already exists, all references
50 cananian 1.1.4.1 * to the existing class are changed to point to the new mutable
51 cananian 1.1.4.1 * class returned by this method. */
52 cananian 1.1.4.1 public HClass createMutableClass(String name, HClass template) {
53 cananian 1.3.2.1 assert template.getLinker()==this;
54 cananian 1.1.4.1 HClass newClass = new HClassSyn(this, name, template);
55 cananian 1.1.4.9 HClass proxyClass = new HClassProxy(this, newClass);
56 cananian 1.1.4.1 newClass.hasBeenModified=true;
57 cananian 1.1.4.1 try {
58 cananian 1.1.4.1 HClass oldClass = forName(name); // get existing proxy class
59 cananian 1.1.4.1 if (oldClass.equals(template))
60 cananian 1.1.4.1 newClass.hasBeenModified=false; // exact copy of oldClass
61 cananian 1.1.4.9 relink(oldClass, proxyClass);
62 cananian 1.1.4.1 return oldClass;
63 cananian 1.1.4.1 } catch (NoSuchClassException e) { // brand spankin' new class
64 cananian 1.1.4.1 register(proxyClass);
65 cananian 1.1.4.1 return proxyClass;
66 cananian 1.1.4.1 }
67 cananian 1.1.4.1 }
68 cananian 1.1.4.1
69 cananian 1.1.4.1 /** Globally replace all references to <code>oldClass</code> with
70 cananian 1.1.4.1 * references to <code>newClass</code>, which may or may not have
71 cananian 1.1.4.1 * the same name. The following constraint must hold:<pre>
72 cananian 1.1.4.1 * oldClass.getLinker()==newClass.getLinker()==this
73 cananian 1.1.4.1 * </pre><p>
74 cananian 1.1.4.1 * <b>WARNING:</b> the <code>hasBeenModified()</code> method of
75 cananian 1.1.4.1 * <code>HClass</code>is not reliable after calling
76 cananian 1.1.4.1 * <code>relink()</code> if <code>oldClass.getName()</code> is not the
77 cananian 1.1.4.1 * same as <code>newClass.getName()</code>. The value returned
78 cananian 1.1.4.1 * by <code>HClass.hasBeenModified()</code> will not reflect changes
79 cananian 1.1.4.1 * due to the global replacement of <code>oldClass</code> with
80 cananian 1.1.4.1 * <code>newClass</code> done by this <code>relink()</code>.</p>
81 cananian 1.1.4.1 */
82 cananian 1.1.4.1 public void relink(HClass oldClass, HClass newClass) {
83 cananian 1.1.4.4 // XXX this can cause some .equals() weirdness!
84 cananian 1.3.2.1 assert oldClass.getLinker()==this;
85 cananian 1.3.2.1 assert newClass.getLinker()==this;
86 cananian 1.1.4.1 // we're going to leave the old mapping in, so that classes
87 cananian 1.1.4.1 // loaded in the future still get the new class. uncomment
88 cananian 1.1.4.1 // out the next line if we decide to delete the old descriptor
89 cananian 1.1.4.1 // mapping when we relink.
90 cananian 1.1.4.1 //descCache.remove(oldClass.getDescriptor());
91 cananian 1.1.4.7 ((HClassProxy)oldClass).relink(((HClassProxy)newClass).proxy);
92 cananian 1.1.4.1 descCache.put(oldClass.getDescriptor(), oldClass);
93 cananian 1.1.4.1 }
94 cananian 1.1.4.10
95 cananian 1.1.4.10 /** Move <code>HMember</code> <code>hm</code> from its declaring
96 cananian 1.1.4.10 * class to some other class, <code>newDestination</code>. This
97 cananian 1.1.4.10 * usually only makes sense if you're moving a member from a
98 cananian 1.1.4.10 * class to its superclass, or vice-versa --- but we're not
99 cananian 1.1.4.10 * enforcing this (full foot-shooting power granted). The
100 cananian 1.1.4.10 * <code>newDestination</code> class must not already have a
101 cananian 1.1.4.10 * field named the same/method with the same signature as
102 cananian 1.1.4.10 * <code>hm</code>. All references to the member in the old class
103 cananian 1.1.4.10 * will be re-directed to point to the member in the new class,
104 cananian 1.1.4.10 * and in fact, upon return the given <code>HMember</code>
105 cananian 1.1.4.10 * <code>hm</code> will refer to the new member.
106 cananian 1.1.4.10 * <b>WARNING</b>: make sure that any methods which refer to this
107 cananian 1.1.4.10 * member have been converted to Bytecode form at least *before*
108 cananian 1.1.4.10 * invoking <code>move()</code>; otherwise field resolution will fail
109 cananian 1.1.4.10 * when we are parsing the bytecode file (we don't keep any record
110 cananian 1.1.4.10 * of the 'old' or 'canonical' name of the moved member).
111 cananian 1.1.4.10 */
112 cananian 1.1.4.10 public void move(HMember hm, HClass newDestination)
113 cananian 1.1.4.10 throws DuplicateMemberException {
114 cananian 1.1.4.10 HClass oldDeclarer = hm.getDeclaringClass();
115 cananian 1.3.2.1 assert oldDeclarer.getLinker()==this;
116 cananian 1.3.2.1 assert newDestination.getLinker()==this;
117 cananian 1.3.2.1 assert hm instanceof HMemberProxy;
118 cananian 1.1.4.10 // make sure both old and new classes are mutable.
119 cananian 1.1.4.10 HClassMutator check;
120 cananian 1.3.2.1 check = oldDeclarer.getMutator(); assert check!=null;
121 cananian 1.3.2.1 check = newDestination.getMutator(); assert check!=null;
122 cananian 1.1.4.10 // access mutator of proxied class directly.
123 cananian 1.1.4.10 HClassMutator oldmut = ((HClassProxy)oldDeclarer).proxyMutator;
124 cananian 1.1.4.10 HClassMutator newmut = ((HClassProxy)newDestination).proxyMutator;
125 cananian 1.1.4.10 // add field/method to (proxied) new class
126 cananian 1.1.4.10 HMember newm = (hm instanceof HField) ? (HMember)
127 cananian 1.1.4.10 newmut.addDeclaredField(hm.getName(), (HField)hm) :
128 cananian 1.1.4.10 (hm instanceof HConstructor) ? (HMember)
129 cananian 1.1.4.10 newmut.addConstructor((HConstructor) hm) :
130 cananian 1.1.4.10 (hm instanceof HInitializer) ? (HMember)
131 cananian 1.1.4.10 newmut.addClassInitializer() :
132 cananian 1.1.4.10 (hm instanceof HMethod) ? (HMember)
133 cananian 1.1.4.10 newmut.addDeclaredMethod(hm.getName(), (HMethod)hm) :
134 cananian 1.1.4.10 null/*should never happen!*/;
135 cananian 1.3.2.1 assert newm!=null : "not a field, method, or constructor";
136 cananian 1.1.4.10 // store away original (old) field.
137 cananian 1.1.4.10 HMember oldm = (hm instanceof HField) ?
138 cananian 1.1.4.10 (HMember) ((HFieldProxy)hm).proxy :
139 cananian 1.1.4.10 (HMember) ((HMethodProxy)hm).proxy;
140 cananian 1.1.4.10 // redirect old field proxy to this new field.
141 cananian 1.1.4.10 int hashcheck = hm.hashCode();
142 cananian 1.1.4.10 if (hm instanceof HField)
143 cananian 1.1.4.10 ((HFieldProxy)hm).relink((HField)newm);
144 cananian 1.1.4.10 else if (hm instanceof HConstructor)
145 cananian 1.1.4.10 ((HConstructorProxy)hm).relink((HConstructor)newm);
146 cananian 1.1.4.10 else if (hm instanceof HInitializer)
147 cananian 1.1.4.10 ((HInitializerProxy)hm).relink((HInitializer)newm);
148 cananian 1.1.4.10 else if (hm instanceof HMethod)
149 cananian 1.1.4.10 ((HMethodProxy)hm).relink((HMethod)newm);
150 cananian 1.3.2.1 else assert false : "not a field, method, or constructor";
151 cananian 1.3.2.1 assert hashcheck==hm.hashCode();// hashcode shouldn't change.
152 cananian 1.1.4.10 // now remove (non-proxied) old field.
153 cananian 1.1.4.10 if (hm instanceof HField)
154 cananian 1.1.4.10 oldmut.removeDeclaredField((HField)oldm);
155 cananian 1.1.4.10 else if (hm instanceof HConstructor)
156 cananian 1.1.4.10 oldmut.removeConstructor((HConstructor)oldm);
157 cananian 1.1.4.10 else if (hm instanceof HInitializer)
158 cananian 1.1.4.10 oldmut.removeClassInitializer((HInitializer)oldm);
159 cananian 1.1.4.10 else if (hm instanceof HMethod)
160 cananian 1.1.4.10 oldmut.removeDeclaredMethod((HMethod)oldm);
161 cananian 1.1.4.10 // update the memberMap
162 cananian 1.1.4.10 memberMap.remove(oldm);
163 cananian 1.1.4.10 memberMap.put(newm, hm);
164 cananian 1.1.4.10 // done!
165 cananian 1.3.2.1 assert hm.getDeclaringClass()==newDestination;
166 cananian 1.1.4.10 }
167 cananian 1.1.4.10
168 cananian 1.1.4.4 // stub to help in reloading proxies.
169 cananian 1.1.4.4 HClassProxy load(String descriptor, HClass proxy) {
170 cananian 1.1.4.4 if (descCache.containsKey(descriptor))
171 cananian 1.1.4.4 ((HClassProxy) descCache.get(descriptor)).relink(proxy);
172 cananian 1.1.4.4 else
173 cananian 1.1.4.4 descCache.put(descriptor, new HClassProxy(this, proxy));
174 cananian 1.1.4.4 return (HClassProxy) descCache.get(descriptor);
175 cananian 1.1.4.4 }
176 cananian 1.1.4.1
177 cananian 1.1.4.3 // Serializable
178 cananian 1.1.4.3 private void readObject(java.io.ObjectInputStream in)
179 cananian 1.1.4.3 throws java.io.IOException, ClassNotFoundException {
180 cananian 1.1.4.3 in.defaultReadObject();
181 cananian 1.1.4.8 // create new memberMap
182 cananian 1.1.4.3 // note that linker descCache is cleared magically on read, too.
183 cananian 1.1.4.3 memberMap = new HashMap();
184 cananian 1.1.4.8 // now restore the "odd" entries in the descCache.
185 cananian 1.1.4.8 for (Iterator it=((List)in.readObject()).iterator(); it.hasNext(); ) {
186 cananian 1.1.4.8 String descK = (String) it.next();
187 cananian 1.1.4.8 String descV = (String) it.next();
188 cananian 1.1.4.8 relink(forDescriptor(descK),forDescriptor(descV));
189 cananian 1.1.4.8 }
190 cananian 1.1.4.8 // done.
191 cananian 1.1.4.8 }
192 cananian 1.1.4.8 private void writeObject(java.io.ObjectOutputStream out)
193 cananian 1.1.4.8 throws java.io.IOException {
194 cananian 1.1.4.8 out.defaultWriteObject();
195 cananian 1.1.4.8 // write out list of relinked descriptors.
196 cananian 1.1.4.8 List l = new ArrayList();
197 cananian 1.6 for (Object descKO : descCache.keySet()) {
198 cananian 1.6 String descK = (String) descKO;
199 cananian 1.1.4.8 String descV = forDescriptor(descK).getDescriptor();
200 cananian 1.1.4.8 if (descK.equals(descV)) continue; // not an interesting entry.
201 cananian 1.1.4.8 l.add(descK); l.add(descV);
202 cananian 1.1.4.8 }
203 cananian 1.1.4.8 out.writeObject(l);
204 cananian 1.1.4.3 }
205 cananian 1.1.4.3
206 cananian 1.1.4.1 // WRAP/UNWRAP CODE
207 cananian 1.1.4.3 transient Map memberMap = new HashMap();
208 cananian 1.1.4.1
209 cananian 1.1.4.1 HClass wrap(HClass hc) {
210 cananian 1.1.4.1 if (hc==null || hc.isPrimitive()) return hc;
211 cananian 1.1.4.1 return forDescriptor(hc.getDescriptor());
212 cananian 1.1.4.1 }
213 cananian 1.1.4.1 HClass unwrap(HClass hc) {
214 cananian 1.1.4.1 if (hc==null || hc.isPrimitive()) return hc;
215 bdemsky 1.1.4.12 /* If we "promote" the original class to an HClassSyn (to modify it)
216 bdemsky 1.1.4.12 * we must still 'unwrap' it to the unmodified version from the
217 bdemsky 1.1.4.12 * original linker, or reference-equality tests against it will fail.
218 bdemsky 1.1.4.12 * Example: searching for method foo(Object o) of class A after we've
219 bdemsky 1.1.4.12 * added a new field to Object. Class A's method descriptor will
220 bdemsky 1.1.4.12 * still reference the "old" Object class. */
221 cananian 1.1.4.6 if (((HClassProxy)hc).sameLinker)
222 cananian 1.1.4.4 return linker.forDescriptor(hc.getDescriptor());
223 cananian 1.1.4.1 return ((HClassProxy)hc).proxy;
224 cananian 1.1.4.1 }
225 cananian 1.1.4.1 HField wrap(HField hf) {
226 cananian 1.1.4.1 if (hf==null) return null;
227 cananian 1.3.2.1 assert !(hf instanceof HFieldProxy &&
228 cananian 1.3.2.1 ((HFieldProxy)hf).relinker==this) : "should never try to proxy a proxy of this same relinker";
229 cananian 1.1.4.1 HField result = (HField) memberMap.get(hf);
230 cananian 1.1.4.1 if (result==null) {
231 cananian 1.1.4.6 result = new HFieldProxy(this, hf);
232 cananian 1.3.2.1 assert result.getDeclaringClass().getLinker()==this;
233 cananian 1.1.4.1 memberMap.put(hf, result);
234 cananian 1.1.4.1 }
235 cananian 1.1.4.1 return result;
236 cananian 1.1.4.1 }
237 cananian 1.1.4.1 HMethod wrap(HMethod hm) {
238 cananian 1.1.4.1 if (hm==null) return null;
239 cananian 1.3.2.1 assert !(hm instanceof HMethodProxy &&
240 cananian 1.3.2.1 ((HMethodProxy)hm).relinker==this) : "should never try to proxy a proxy of this same relinker";
241 cananian 1.1.4.1 if (hm instanceof HInitializer) return wrap((HInitializer)hm);
242 cananian 1.1.4.1 if (hm instanceof HConstructor) return wrap((HConstructor)hm);
243 cananian 1.1.4.1 HMethod result = (HMethodProxy) memberMap.get(hm);
244 cananian 1.1.4.1 if (result==null) {
245 cananian 1.1.4.6 result = new HMethodProxy(this, hm);
246 cananian 1.3.2.1 assert result.getDeclaringClass().getLinker()==this;
247 cananian 1.1.4.1 memberMap.put(hm, result);
248 cananian 1.1.4.1 }
249 cananian 1.1.4.1 return result;
250 cananian 1.1.4.1 }
251 cananian 1.1.4.1 HConstructor wrap(HConstructor hc) {
252 cananian 1.1.4.1 if (hc==null) return null;
253 cananian 1.1.4.1 HConstructor result = (HConstructorProxy) memberMap.get(hc);
254 cananian 1.1.4.1 if (result==null) {
255 cananian 1.3.2.1 assert !hc.getDeclaringClass().isArray();
256 cananian 1.1.4.1 result = new HConstructorProxy(this, hc);
257 cananian 1.1.4.1 memberMap.put(hc, result);
258 cananian 1.1.4.1 }
259 cananian 1.1.4.1 return result;
260 cananian 1.1.4.1 }
261 cananian 1.1.4.1 HInitializer wrap(HInitializer hi) {
262 cananian 1.1.4.1 if (hi==null) return null;
263 cananian 1.1.4.1 HInitializer result = (HInitializerProxy) memberMap.get(hi);
264 cananian 1.1.4.1 if (result==null) {
265 cananian 1.3.2.1 assert !hi.getDeclaringClass().isArray();
266 cananian 1.1.4.1 result = new HInitializerProxy(this, hi);
267 cananian 1.1.4.1 memberMap.put(hi, result);
268 cananian 1.1.4.1 }
269 cananian 1.1.4.1 return result;
270 cananian 1.1.4.1 }
271 cananian 1.1.4.1 // array wrap/unwrap
272 cananian 1.1.4.1 HClass[] wrap(HClass hc[]) {
273 cananian 1.1.4.1 HClass[] result = new HClass[hc.length];
274 cananian 1.1.4.1 for (int i=0; i<result.length; i++)
275 cananian 1.1.4.1 result[i] = wrap(hc[i]);
276 cananian 1.1.4.1 return result;
277 cananian 1.1.4.1 }
278 cananian 1.1.4.1 HClass[] unwrap(HClass[] hc) {
279 cananian 1.1.4.1 HClass[] result = new HClass[hc.length];
280 cananian 1.1.4.1 for (int i=0; i<result.length; i++)
281 cananian 1.1.4.1 result[i] = unwrap(hc[i]);
282 cananian 1.1.4.1 return result;
283 cananian 1.1.4.1 }
284 cananian 1.1.4.1 HField[] wrap(HField hf[]) {
285 cananian 1.1.4.1 HField[] result = new HField[hf.length];
286 cananian 1.1.4.1 for (int i=0; i<result.length; i++)
287 cananian 1.1.4.1 result[i] = wrap(hf[i]);
288 cananian 1.1.4.1 return result;
289 cananian 1.1.4.1 }
290 cananian 1.1.4.1 HMethod[] wrap(HMethod hm[]) {
291 cananian 1.1.4.1 HMethod[] result = new HMethod[hm.length];
292 cananian 1.1.4.1 for (int i=0; i<result.length; i++)
293 cananian 1.1.4.1 result[i] = wrap(hm[i]);
294 cananian 1.1.4.1 return result;
295 cananian 1.1.4.1 }
296 cananian 1.1.4.1 HConstructor[] wrap(HConstructor hc[]) {
297 cananian 1.1.4.1 HConstructor[] result = new HConstructor[hc.length];
298 cananian 1.1.4.1 for (int i=0; i<result.length; i++)
299 cananian 1.1.4.1 result[i] = wrap(hc[i]);
300 cananian 1.1.4.1 return result;
301 cananian 1.1.4.1 }
302 cananian 1.2 }