1/*
2 * Copyright (c) 2015, 2017, Oracle and/or its affiliates. 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.  Oracle designates this
8 * particular file as subject to the "Classpath" exception as provided
9 * by Oracle in the LICENSE file that accompanied this code.
10 *
11 * This code is distributed in the hope that it will be useful, but WITHOUT
12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
14 * version 2 for more details (a copy is included in the LICENSE file that
15 * accompanied this code).
16 *
17 * You should have received a copy of the GNU General Public License version
18 * 2 along with this work; if not, write to the Free Software Foundation,
19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
20 *
21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
22 * or visit www.oracle.com if you need additional information or have any
23 * questions.
24 */
25package java.lang;
26
27final class LiveStackFrameInfo extends StackFrameInfo implements LiveStackFrame {
28    private static Object[] EMPTY_ARRAY = new Object[0];
29
30    // These flags must match the values maintained in the VM
31    private static final int MODE_INTERPRETED = 0x01;
32    private static final int MODE_COMPILED    = 0x02;
33
34    LiveStackFrameInfo(StackWalker walker) {
35        super(walker);
36    }
37
38    // These fields are initialized by the VM if ExtendedOption.LOCALS_AND_OPERANDS is set
39    private Object[] monitors = EMPTY_ARRAY;
40    private Object[] locals = EMPTY_ARRAY;
41    private Object[] operands = EMPTY_ARRAY;
42    private int mode = 0;
43
44    @Override
45    public Object[] getMonitors() {
46        return monitors;
47    }
48
49    @Override
50    public Object[] getLocals() {
51        return locals;
52    }
53
54    @Override
55    public Object[] getStack() {
56        return operands;
57    }
58
59    @Override
60    public String toString() {
61        StringBuilder retVal = new StringBuilder(super.toString());
62        if (mode != 0) {
63            retVal.append("(");
64            if ((mode & MODE_INTERPRETED) == MODE_INTERPRETED) {
65                retVal.append(" interpreted ");
66            }
67            if ((mode & MODE_COMPILED) == MODE_COMPILED) {
68                retVal.append(" compiled ");
69            }
70            retVal.append(")");
71        }
72        return retVal.toString();
73    }
74
75    /*
76     * Convert primitive value to {@code PrimitiveSlot} object to represent
77     * a local variable or an element on the operand stack of primitive type.
78     */
79
80    static PrimitiveSlot asPrimitive(int value) {
81        return new PrimitiveSlot32(value);
82    }
83
84    static PrimitiveSlot asPrimitive(long value) {
85        return new PrimitiveSlot64(value);
86    }
87
88    private static class PrimitiveSlot32 extends PrimitiveSlot {
89        final int value;
90        PrimitiveSlot32(int value) {
91            this.value = value;
92        }
93
94        @Override
95        public int size() {
96            return 4;
97        }
98
99        @Override
100        public int intValue() {
101            return value;
102        }
103
104        @Override
105        public String toString() {
106            return String.valueOf(value);
107        }
108    }
109
110    private static class PrimitiveSlot64 extends PrimitiveSlot {
111        final long value;
112        PrimitiveSlot64(long value) {
113            this.value = value;
114        }
115
116        @Override
117        public int size() {
118            return 8;
119        }
120
121        @Override
122        public long longValue() {
123            return value;
124        }
125
126        @Override
127        public String toString() {
128            return String.valueOf(value);
129        }
130    }
131}
132