1 /*
2 * Copyright 2000-2007 Sun Microsystems, Inc. All Rights Reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
20 * CA 95054 USA or visit www.sun.com if you need additional information or
21 * have any questions.
22 *
23 */
24
25 package sun.jvm.hotspot.oops;
26
27 import java.io.*;
28 import java.util.*;
29 import sun.jvm.hotspot.debugger.*;
30 import sun.jvm.hotspot.runtime.*;
31 import sun.jvm.hotspot.types.*;
32
33 public class Klass extends Oop implements ClassConstants {
34 static {
35 VM.registerVMInitializedObserver(new Observer() {
36 public void update(Observable o, Object data) {
37 initialize(VM.getVM().getTypeDataBase());
38 }
39 });
40 }
41
42 // anon-enum constants for _layout_helper.
43 public static int LH_INSTANCE_SLOW_PATH_BIT;
44 public static int LH_LOG2_ELEMENT_SIZE_SHIFT;
45 public static int LH_ELEMENT_TYPE_SHIFT;
46 public static int LH_HEADER_SIZE_SHIFT;
47 public static int LH_ARRAY_TAG_SHIFT;
48 public static int LH_ARRAY_TAG_TYPE_VALUE;
49 public static int LH_ARRAY_TAG_OBJ_VALUE;
50
51 private static synchronized void initialize(TypeDataBase db) throws WrongTypeException {
52 Type type = db.lookupType("Klass");
53 javaMirror = new OopField(type.getOopField("_java_mirror"), Oop.getHeaderSize());
54 superField = new OopField(type.getOopField("_super"), Oop.getHeaderSize());
55 layoutHelper = new IntField(type.getJIntField("_layout_helper"), Oop.getHeaderSize());
56 name = new OopField(type.getOopField("_name"), Oop.getHeaderSize());
57 accessFlags = new CIntField(type.getCIntegerField("_access_flags"), Oop.getHeaderSize());
58 subklass = new OopField(type.getOopField("_subklass"), Oop.getHeaderSize());
59 nextSibling = new OopField(type.getOopField("_next_sibling"), Oop.getHeaderSize());
60 allocCount = new CIntField(type.getCIntegerField("_alloc_count"), Oop.getHeaderSize());
61
62 LH_INSTANCE_SLOW_PATH_BIT = db.lookupIntConstant("Klass::_lh_instance_slow_path_bit").intValue();
63 LH_LOG2_ELEMENT_SIZE_SHIFT = db.lookupIntConstant("Klass::_lh_log2_element_size_shift").intValue();
64 LH_ELEMENT_TYPE_SHIFT = db.lookupIntConstant("Klass::_lh_element_type_shift").intValue();
65 LH_HEADER_SIZE_SHIFT = db.lookupIntConstant("Klass::_lh_header_size_shift").intValue();
66 LH_ARRAY_TAG_SHIFT = db.lookupIntConstant("Klass::_lh_array_tag_shift").intValue();
67 LH_ARRAY_TAG_TYPE_VALUE = db.lookupIntConstant("Klass::_lh_array_tag_type_value").intValue();
68 LH_ARRAY_TAG_OBJ_VALUE = db.lookupIntConstant("Klass::_lh_array_tag_obj_value").intValue();
69 }
70
71 Klass(OopHandle handle, ObjectHeap heap) {
72 super(handle, heap);
73 }
74
75 // jvmdi support - see also class_status in VM code
76 public int getClassStatus() {
77 return 0; // overridden in derived classes
78 }
79
80 public boolean isKlass() { return true; }
81
82 // Fields
83 private static OopField javaMirror;
84 private static OopField superField;
85 private static IntField layoutHelper;
86 private static OopField name;
87 private static CIntField accessFlags;
88 private static OopField subklass;
89 private static OopField nextSibling;
90 private static CIntField allocCount;
91
92 // Accessors for declared fields
93 public Instance getJavaMirror() { return (Instance) javaMirror.getValue(this); }
94 public Klass getSuper() { return (Klass) superField.getValue(this); }
95 public Klass getJavaSuper() { return null; }
96 public int getLayoutHelper() { return (int) layoutHelper.getValue(this); }
97 public Symbol getName() { return (Symbol) name.getValue(this); }
98 public long getAccessFlags() { return accessFlags.getValue(this); }
99 // Convenience routine
100 public AccessFlags getAccessFlagsObj(){ return new AccessFlags(getAccessFlags()); }
101 public Klass getSubklassKlass() { return (Klass) subklass.getValue(this); }
102 public Klass getNextSiblingKlass() { return (Klass) nextSibling.getValue(this); }
103 public long getAllocCount() { return allocCount.getValue(this); }
104
105 // computed access flags - takes care of inner classes etc.
106 // This is closer to actual source level than getAccessFlags() etc.
107 public long computeModifierFlags() {
108 return 0L; // Unless overridden, modifier_flags is 0.
109 }
110
111 // same as JVM_GetClassModifiers
112 public final long getClassModifiers() {
113 // unlike the VM counterpart we never have to deal with primitive type,
114 // because we operator on Klass and not an instance of java.lang.Class.
115 long flags = computeModifierFlags();
116 if (isSuper()) {
117 flags |= JVM_ACC_SUPER;
118 }
119 return flags;
120 }
121
122 // subclass check
123 public boolean isSubclassOf(Klass k) {
124 if (k != null) {
125 Klass t = this;
126 // Run up the super chain and check
127 while (t != null) {
128 if (t.equals(k)) return true;
129 t = t.getSuper();
130 }
131 }
132 return false;
133 }
134
135 // subtype check
136 public boolean isSubtypeOf(Klass k) {
137 return computeSubtypeOf(k);
138 }
139
140 boolean computeSubtypeOf(Klass k) {
141 return isSubclassOf(k);
142 }
143
144 // Find LCA (Least Common Ancester) in class heirarchy
145 public Klass lca( Klass k2 ) {
146 Klass k1 = this;
147 while ( true ) {
148 if ( k1.isSubtypeOf(k2) ) return k2;
149 if ( k2.isSubtypeOf(k1) ) return k1;
150 k1 = k1.getSuper();
151 k2 = k2.getSuper();
152 }
153 }
154
155 public void printValueOn(PrintStream tty) {
156 tty.print("Klass");
157 }
158
159 public void iterateFields(OopVisitor visitor, boolean doVMFields) {
160 super.iterateFields(visitor, doVMFields);
161 if (doVMFields) {
162 visitor.doOop(javaMirror, true);
163 visitor.doOop(superField, true);
164 visitor.doInt(layoutHelper, true);
165 visitor.doOop(name, true);
166 visitor.doCInt(accessFlags, true);
167 visitor.doOop(subklass, true);
168 visitor.doOop(nextSibling, true);
169 visitor.doCInt(allocCount, true);
170 }
171 }
172
173 public long getObjectSize() {
174 System.out.println("should not reach here");
175 return 0;
176 }
177
178 /** Array class with specific rank */
179 public Klass arrayKlass(int rank) { return arrayKlassImpl(false, rank); }
180 /** Array class with this klass as element type */
181 public Klass arrayKlass() { return arrayKlassImpl(false); }
182 /** These will return null instead of allocating on the heap */
183 public Klass arrayKlassOrNull(int rank) { return arrayKlassImpl(true, rank); }
184 public Klass arrayKlassOrNull() { return arrayKlassImpl(true); }
185
186 public Klass arrayKlassImpl(boolean orNull, int rank) {
187 throw new RuntimeException("array_klass should be dispatched to instanceKlass, objArrayKlass or typeArrayKlass");
188 }
189
190 public Klass arrayKlassImpl(boolean orNull) {
191 throw new RuntimeException("array_klass should be dispatched to instanceKlass, objArrayKlass or typeArrayKlass");
192 }
193
194 // This returns the name in the form java/lang/String which isn't really a signature
195 // The subclasses override this to produce the correct form, eg
196 // Ljava/lang/String; For ArrayKlasses getName itself is the signature.
197 public String signature() { return getName().asString(); }
198
199 // Convenience routines
200 public boolean isPublic() { return getAccessFlagsObj().isPublic(); }
201 public boolean isFinal() { return getAccessFlagsObj().isFinal(); }
202 public boolean isInterface() { return getAccessFlagsObj().isInterface(); }
203 public boolean isAbstract() { return getAccessFlagsObj().isAbstract(); }
204 public boolean isSuper() { return getAccessFlagsObj().isSuper(); }
205 public boolean isSynthetic() { return getAccessFlagsObj().isSynthetic(); }
206 public boolean hasFinalizer() { return getAccessFlagsObj().hasFinalizer(); }
207 public boolean isCloneable() { return getAccessFlagsObj().isCloneable(); }
208 public boolean hasVanillaConstructor() { return getAccessFlagsObj().hasVanillaConstructor(); }
209 public boolean hasMirandaMethods () { return getAccessFlagsObj().hasMirandaMethods(); }
210 }