1 cananian 1.1.2.5 // ObjectRef.java, created Sat Mar 27 17:05:09 1999 by duncan
2 cananian 1.1.2.4 // Copyright (C) 1998 C. Scott Ananian <cananian@alumni.princeton.edu>
3 cananian 1.1.2.4 // Licensed under the terms of the GNU GPL; see COPYING for details.
4 duncan 1.1.2.1 package harpoon.Interpret.Tree;
5 duncan 1.1.2.1
6 duncan 1.1.2.1 import harpoon.ClassFile.HClass;
7 duncan 1.1.2.1 import harpoon.ClassFile.HField;
8 duncan 1.1.2.1 import harpoon.ClassFile.HMethod;
9 duncan 1.1.2.1 import harpoon.IR.Tree.NAME;
10 duncan 1.1.2.1 import harpoon.Util.Util;
11 duncan 1.1.2.1
12 duncan 1.1.2.1 /**
13 duncan 1.1.2.1 * <code>ObjectRef</code> is an object reference in the interpreter.
14 duncan 1.1.2.1 *
15 duncan 1.1.2.1 * @author C. Scott Ananian <cananian@alumni.princeton.edu>
16 cananian 1.4 * @version $Id: ObjectRef.java,v 1.4 2002/04/10 03:06:00 cananian Exp $
17 duncan 1.1.2.1 */
18 duncan 1.1.2.1 class ObjectRef extends Ref {
19 duncan 1.1.2.1
20 duncan 1.1.2.1 private Integer hashCode;
21 duncan 1.1.2.1 private ClazPointer classPtr;
22 duncan 1.1.2.1
23 duncan 1.1.2.1 /** Fields in this instance of the object. */
24 duncan 1.1.2.1 FieldValueList fields;
25 duncan 1.1.2.1 /** Native method closure. */
26 duncan 1.1.2.1 Object closure;
27 duncan 1.1.2.1
28 duncan 1.1.2.1 /** create a new objectref with default field values.
29 duncan 1.1.2.1 * @exception InterpretedThrowable
30 duncan 1.1.2.1 * if class initializer throws an exception. */
31 duncan 1.1.2.1 ObjectRef(StaticState ss, HClass type) {
32 duncan 1.1.2.1 this(ss, type, null, null);
33 duncan 1.1.2.1 }
34 duncan 1.1.2.1
35 duncan 1.1.2.1 /** create a new objectref with default field values.
36 duncan 1.1.2.1 * @exception InterpretedThrowable
37 duncan 1.1.2.1 * if class initializer throws an exception. */
38 duncan 1.1.2.1 ObjectRef(StaticState ss, HClass type,
39 duncan 1.1.2.1 Integer hashCode, ClazPointer classPtr) {
40 duncan 1.1.2.1 super(ss, type);
41 duncan 1.1.2.1 this.fields = null;
42 duncan 1.1.2.1 this.closure = null;
43 duncan 1.1.2.1 this.hashCode = hashCode==null?new Integer(this.hashCode()):hashCode;
44 duncan 1.1.2.1 this.classPtr = classPtr==null?
45 duncan 1.1.2.2 new ClazPointer(ss.map.label(type), ss, 0):
46 duncan 1.1.2.2 classPtr;
47 duncan 1.1.2.1
48 duncan 1.1.2.1 // Initialize our fields.
49 duncan 1.1.2.1 for (HClass sc=type; sc!=null; sc=sc.getSuperclass()) {
50 duncan 1.1.2.1 HField[] fl = sc.getDeclaredFields();
51 duncan 1.1.2.1 for (int i=0; i<fl.length; i++) {
52 duncan 1.1.2.1 if (!fl[i].isStatic()) { update(fl[i], defaultValue(fl[i])); }
53 duncan 1.1.2.1 }
54 duncan 1.1.2.1 }
55 duncan 1.1.2.1 // yay, done.
56 duncan 1.1.2.1 }
57 duncan 1.1.2.1
58 duncan 1.1.2.1 // private constructor for use by the clone() method.
59 duncan 1.1.2.1 private ObjectRef(StaticState ss, HClass type, FieldValueList fields) {
60 duncan 1.1.2.1 super(ss, type);
61 duncan 1.1.2.1 this.fields = fields; this.closure = null;
62 duncan 1.1.2.1 // no field initialization necessary.
63 duncan 1.1.2.1 }
64 duncan 1.1.2.1
65 duncan 1.1.2.1 /** Clones this <code>ObjectRef</code> */
66 duncan 1.1.2.1 public Object clone() {
67 cananian 1.3.2.1 assert closure==null : "can't clone objects with closure info.";
68 duncan 1.1.2.2 return new ObjectRef(ss, type, FieldValueList.clone(fields));
69 duncan 1.1.2.1 }
70 duncan 1.1.2.1
71 duncan 1.1.2.1 /** Calls the <code>finalize()</code> method of the specified
72 duncan 1.1.2.1 * <code>ObjectRef</code> */
73 duncan 1.1.2.1 protected void finalize() throws Throwable {
74 duncan 1.1.2.1 // finalize the referenced object by evaluating its finalize method.
75 duncan 1.1.2.1 try {
76 duncan 1.1.2.1 HMethod hm = type.getMethod("finalize", new HClass[0]);
77 duncan 1.1.2.1 Method.invoke(ss, hm, new Object[] { this } );
78 duncan 1.1.2.1 } catch (InterpretedThrowable e) {
79 duncan 1.1.2.1 // ignore.
80 duncan 1.1.2.1 } catch (NoSuchMethodError e) {
81 duncan 1.1.2.1 // no finalize method.
82 duncan 1.1.2.1 }
83 duncan 1.1.2.1 // finalize the ref.
84 duncan 1.1.2.1 super.finalize();
85 duncan 1.1.2.1 }
86 duncan 1.1.2.1
87 duncan 1.1.2.1 /** Returns the value of the specified field of this <code>ObjectRef</code>
88 duncan 1.1.2.1 */
89 duncan 1.1.2.1 Object get(HField f) {
90 andyb 1.1.2.3 //if (DEBUG) db("Accessing field: " + f + " in " + this);
91 duncan 1.1.2.1 return FieldValueList.get(this.fields, f);
92 duncan 1.1.2.1 }
93 duncan 1.1.2.1
94 duncan 1.1.2.1 /** Returns the native method closure of this <code>ObjectRef</code> */
95 duncan 1.1.2.1 Object getClosure() { return closure; }
96 duncan 1.1.2.1
97 duncan 1.1.2.1 /** Sets the native method closure of this <code>ObjectRef</code> */
98 duncan 1.1.2.1 void putClosure(Object cl) { closure = cl; }
99 duncan 1.1.2.1
100 duncan 1.1.2.1 /** Updates the specified field of this <code>ObjectRef</code> to have
101 duncan 1.1.2.1 * the specified value */
102 duncan 1.1.2.1 void update(HField f, Object value) {
103 andyb 1.1.2.3 //if (DEBUG) db("Updating field " + f + " in " + this + " to " + value);
104 duncan 1.1.2.1 this.fields = FieldValueList.update(this.fields, f, value);
105 duncan 1.1.2.1 }
106 duncan 1.1.2.1
107 duncan 1.1.2.1 /** Dereferences the specified <code>FieldPointer</code> and returns
108 duncan 1.1.2.1 * the value which it points to */
109 duncan 1.1.2.1 static Object get(FieldPointer ptr) {
110 duncan 1.1.2.1 ObjectRef ref = (ObjectRef)ptr.getBase();
111 duncan 1.1.2.1 long offset = ptr.getOffset();
112 duncan 1.1.2.1
113 duncan 1.1.2.1 // case 1: points to hashcode. return field as normal.
114 duncan 1.1.2.1 if (ref.ss.map.hashCodeOffset(ref.type)==offset) {
115 cananian 1.3.2.1 assert ref.hashCode!=null;
116 duncan 1.1.2.1 return ref.hashCode;
117 duncan 1.1.2.1 }
118 duncan 1.1.2.1 // case 2: points to classptr. Return ClazPointer<label, 0>
119 duncan 1.1.2.6 else if (ref.ss.map.clazzPtrOffset(ref.type)==offset) {
120 cananian 1.3.2.1 assert ref.classPtr != null;
121 duncan 1.1.2.1 return ref.classPtr;
122 duncan 1.1.2.1 }
123 duncan 1.1.2.1 // case 3: points to finalization info. Can this happen?
124 duncan 1.1.2.1 // case 4: points to normal info.
125 duncan 1.1.2.1 else {
126 duncan 1.1.2.1 return ref.get(ref.ss.getField(ptr));
127 duncan 1.1.2.1 }
128 duncan 1.1.2.1 }
129 duncan 1.1.2.1
130 duncan 1.1.2.1 /** Updates the location pointed to by <code>ptr</code> to have
131 duncan 1.1.2.1 * the specified value. */
132 duncan 1.1.2.1 static void update(FieldPointer ptr, Object value) {
133 duncan 1.1.2.1 ObjectRef ref = (ObjectRef)ptr.getBase();
134 duncan 1.1.2.1 long offset = ptr.getOffset();
135 duncan 1.1.2.1
136 duncan 1.1.2.1 if (ref.ss.map.hashCodeOffset(ref.type)==offset) {
137 duncan 1.1.2.1 throw new Error("Hashcode field is final!");
138 duncan 1.1.2.1 }
139 duncan 1.1.2.6 else if (ref.ss.map.clazzPtrOffset(ref.type)==offset) {
140 duncan 1.1.2.1 throw new Error("The ClazPointer of an object is final!");
141 duncan 1.1.2.1 }
142 duncan 1.1.2.1 else {
143 duncan 1.1.2.1 ref.update(ref.ss.getField(ptr), value);
144 duncan 1.1.2.1 }
145 duncan 1.1.2.1 }
146 duncan 1.1.2.2
147 duncan 1.1.2.2 /** Returns a human-readable representation of this <code>ObjectRef</code>
148 duncan 1.1.2.2 */
149 duncan 1.1.2.2 /*
150 duncan 1.1.2.2 public String toString() {
151 duncan 1.1.2.2 String fString;
152 duncan 1.1.2.2 if (fields==null) fString=null;
153 duncan 1.1.2.2 else fString = fields.toString();
154 duncan 1.1.2.2
155 duncan 1.1.2.2 return "ObjectRef < " + type + ", " + fString;
156 duncan 1.1.2.2
157 duncan 1.1.2.2 }
158 duncan 1.1.2.2 */
159 duncan 1.1.2.1 }
160 duncan 1.1.2.1
161 duncan 1.1.2.1
162 duncan 1.1.2.1
163 cananian 1.2