1 cananian 1.1 // AbstractClassFixupRelinker.java, created Fri Jul 5 20:25:45 2002 by cananian
2 cananian 1.1 // Copyright (C) 2000 C. Scott Ananian <cananian@alumni.princeton.edu>
3 cananian 1.1 // Licensed under the terms of the GNU GPL; see COPYING for details.
4 cananian 1.1 package harpoon.Analysis;
5 cananian 1.1
6 cananian 1.1 import harpoon.ClassFile.HClass;
7 cananian 1.4 import harpoon.ClassFile.HInitializer;
8 cananian 1.5 import harpoon.ClassFile.HField;
9 cananian 1.1 import harpoon.ClassFile.HMethod;
10 cananian 1.1 import harpoon.ClassFile.Linker;
11 cananian 1.1 import harpoon.ClassFile.Relinker;
12 cananian 1.1 import harpoon.Util.ArrayIterator;
13 cananian 1.10 import net.cscott.jutil.UniqueVector;
14 cananian 1.10 import net.cscott.jutil.WorkSet;
15 cananian 1.1
16 cananian 1.1 import java.lang.reflect.Modifier;
17 cananian 1.9 import java.util.HashSet;
18 cananian 1.9 import java.util.Iterator;
19 cananian 1.9 import java.util.Set;
20 cananian 1.1 /**
21 cananian 1.1 * <code>AbstractClassFixupRelinker</code> is an extension of <code>Relinker</code>
22 cananian 1.1 * which fixes up abstract classes so that they implement all the methods
23 cananian 1.1 * of their interfaces (even if this implementation is via an abstract
24 cananian 1.1 * method declaration). The newer JDK1.4 compiler that Sun provides does
25 cananian 1.1 * not put these method declarations in by default, unlike earlier
26 cananian 1.1 * compilers, and this violates several assumptions made in FLEX.
27 cananian 1.1 * The <code>AbstractClassFixupRelinker</code> remedies the situation.
28 cananian 1.1 *
29 cananian 1.1 * @author C. Scott Ananian <cananian@alumni.princeton.edu>
30 cananian 1.11 * @version $Id: AbstractClassFixupRelinker.java,v 1.11 2004/02/08 03:19:12 cananian Exp $
31 cananian 1.1 */
32 cananian 1.1 public class AbstractClassFixupRelinker extends Relinker {
33 cananian 1.1
34 cananian 1.1 /** Creates a <code>AbstractClassFixupRelinker</code>. */
35 cananian 1.1 public AbstractClassFixupRelinker(Linker linker) {
36 cananian 1.1 super(linker);
37 cananian 1.1 }
38 wbeebee 1.7
39 cananian 1.1 public HClass forDescriptor(String descriptor) {
40 wbeebee 1.7 // We want to make sure that Linker.forDescriptor completes
41 wbeebee 1.7 // entirely (entering the new class in the descriptor cache)
42 wbeebee 1.7 // before we invoke it again. HOWEVER, Linker.forDescriptor
43 wbeebee 1.7 // will call *us* recursively e.g. to resolve arrays. So it's
44 wbeebee 1.7 // not safe to do our resolve() stuff (which will indirectly
45 wbeebee 1.7 // cause further calls to Linker.forDescriptor) until we're
46 wbeebee 1.7 // sure the top-level call to Linker.forDescriptor has finished.
47 wbeebee 1.7 // The 'depth' variable here basically just keeps track of
48 wbeebee 1.7 // whether this is a recursive invocation via Linker.forDescriptor
49 wbeebee 1.7 // or a 'top-level' one; we only resolve after top-level calls.
50 wbeebee 1.7 depth++;
51 cananian 1.1 HClass hc = super.forDescriptor(descriptor);
52 wbeebee 1.7 depth--;
53 wbeebee 1.7 deferred.add(hc);
54 wbeebee 1.7 if (depth==0) // this is a top-level call, it's safe to resolve.
55 wbeebee 1.7 while (!deferred.isEmpty())
56 wbeebee 1.7 resolve(deferred.removeFirst());
57 wbeebee 1.7 return hc;
58 wbeebee 1.7 }
59 wbeebee 1.7 /** Set of classes waiting to be fixed up. */
60 wbeebee 1.7 WorkSet<HClass> deferred = new WorkSet<HClass>();
61 wbeebee 1.7 /** Current level of recursion. */
62 wbeebee 1.7 int depth=0;
63 wbeebee 1.7
64 wbeebee 1.7 public HClass resolve(HClass hc) {
65 cananian 1.1 // okay, now scan the class and fix it up.
66 cananian 1.1 if (!hc.isInterface() && !done.contains(hc)) {
67 cananian 1.2 done.add(hc);// properly handle incidental recursion inside fixup()
68 cananian 1.2 // we should first fix up the superclass(es), if any.
69 cananian 1.1 HClass sc = hc.getSuperclass();
70 wbeebee 1.7 if (sc!=null) resolve(sc); // recurse!
71 cananian 1.1 // okay, now fix this class up.
72 cananian 1.1 fixup(hc);
73 cananian 1.6
74 cananian 1.6 // and to prevent fixup from happening at inopportune times
75 cananian 1.6 // (such as after we start modifying method signatures)
76 cananian 1.6 // we're going to be aggressive in fixing up other classes
77 cananian 1.6 // mentioned in fields and methods of this one.
78 cananian 1.6
79 cananian 1.6 // fix up classes mentioned in method signatures
80 cananian 1.11 for (HMethod hm : hc.getDeclaredMethods()) {
81 wbeebee 1.7 resolve(hm.getReturnType());
82 cananian 1.5 for (Iterator<HClass> it2=new ArrayIterator<HClass>
83 cananian 1.5 (hm.getParameterTypes()); it2.hasNext(); )
84 wbeebee 1.7 resolve(it2.next());
85 cananian 1.5 }
86 cananian 1.5 // and those in field signatures.
87 cananian 1.5 for (Iterator<HField> it=new ArrayIterator<HField>
88 cananian 1.5 (hc.getDeclaredFields()); it.hasNext(); )
89 wbeebee 1.7 resolve(it.next().getType());
90 cananian 1.1 }
91 cananian 1.1 // done!
92 cananian 1.1 return hc;
93 cananian 1.1 }
94 cananian 1.3 private static Set<HClass> done = new HashSet<HClass>();
95 cananian 1.1
96 cananian 1.1 private void fixup(HClass hc) {
97 cananian 1.1 for (Iterator<HClass> it=collectInterfaces(hc).iterator();
98 cananian 1.1 it.hasNext(); )
99 cananian 1.1 fixupOne(hc, it.next());
100 cananian 1.1 }
101 cananian 1.1 private void fixupOne(HClass hc, HClass anInterface) {
102 cananian 1.1 assert !hc.isInterface();
103 cananian 1.1 assert anInterface.isInterface();
104 cananian 1.1 // get list of interface methods.
105 cananian 1.11 for (HMethod hm : anInterface.getDeclaredMethods()) {
106 cananian 1.4 // could be a static initializer of the interface.
107 cananian 1.4 if (hm instanceof HInitializer) continue;
108 cananian 1.4 // otherwise this should be an interface method.
109 cananian 1.1 assert hm.isInterfaceMethod();
110 cananian 1.1 // okay, look this up as a method of hc. if it doesn't exist,
111 cananian 1.1 // create it as a public abstract method.
112 cananian 1.1 HMethod hmm = hc.getMethod(hm.getName(), hm.getParameterTypes());
113 cananian 1.1 if (hmm.isInterfaceMethod()) {
114 cananian 1.1 // NOT IMPLEMENTED IN CLASS! this better be an abstract class:
115 cananian 1.1 assert Modifier.isAbstract(hc.getModifiers()) :
116 cananian 1.1 "interface method "+hm+" not implemented in non-abstract "+
117 cananian 1.1 "class "+hc;
118 cananian 1.1 // okay, it's an abstract class, so make an abstract
119 cananian 1.1 // implementation method.
120 cananian 1.1 HMethod nm=hc.getMutator().addDeclaredMethod
121 cananian 1.1 (hm.getName(), hm.getDescriptor());
122 cananian 1.1 nm.getMutator().setModifiers
123 cananian 1.1 (Modifier.PUBLIC | Modifier.ABSTRACT);
124 cananian 1.1 nm.getMutator().setExceptionTypes(hm.getExceptionTypes());
125 cananian 1.1 }
126 cananian 1.1 }
127 cananian 1.1 }
128 cananian 1.1
129 cananian 1.1 private static Set<HClass> collectInterfaces(HClass hc) {
130 cananian 1.1 UniqueVector<HClass> uv = new UniqueVector<HClass>();
131 cananian 1.1 for (Iterator<HClass> it=new ArrayIterator<HClass>(hc.getInterfaces());
132 cananian 1.1 it.hasNext(); )
133 cananian 1.1 uv.add(it.next());
134 cananian 1.1 // okay, uv now has the basic interfaces. we just have to
135 cananian 1.1 // go through it from beginning to end to add all superinterfaces.
136 cananian 1.1 for (int i=0; i<uv.size(); i++)
137 cananian 1.1 for (Iterator<HClass> it=new ArrayIterator<HClass>
138 cananian 1.1 (uv.get(i).getInterfaces()); it.hasNext(); )
139 cananian 1.1 uv.add(it.next());
140 cananian 1.1 // done!
141 cananian 1.1 return uv;
142 cananian 1.1 }
143 cananian 1.1 }