1 /*
2 * Copyright (c) 2009, 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 */
25
26 package com.sun.tools.javap;
27
28 import com.sun.tools.classfile.Attribute;
29 import com.sun.tools.classfile.Code_attribute;
30 import com.sun.tools.classfile.ConstantPool;
31 import com.sun.tools.classfile.ConstantPoolException;
32 import com.sun.tools.classfile.Descriptor;
33 import com.sun.tools.classfile.Descriptor.InvalidDescriptor;
34 import com.sun.tools.classfile.Instruction;
35 import com.sun.tools.classfile.LocalVariableTypeTable_attribute;
36 import com.sun.tools.classfile.Signature;
37 import java.util.ArrayList;
38 import java.util.HashMap;
39 import java.util.List;
40 import java.util.ListIterator;
41 import java.util.Map;
42
43 /**
44 * Annotate instructions with details about local variables.
45 *
46 * <p><b>This is NOT part of any supported API.
47 * If you write code that depends on this, you do so at your own risk.
48 * This code and its internal interfaces are subject to change or
49 * deletion without notice.</b>
50 */
51 public class LocalVariableTypeTableWriter extends InstructionDetailWriter {
52 public enum NoteKind {
53 START("start") {
54 public boolean match(LocalVariableTypeTable_attribute.Entry entry, int pc) {
55 return (pc == entry.start_pc);
56 }
57 },
58 END("end") {
59 public boolean match(LocalVariableTypeTable_attribute.Entry entry, int pc) {
60 return (pc == entry.start_pc + entry.length);
61 }
62 };
63 NoteKind(String text) {
64 this.text = text;
65 }
66 public abstract boolean match(LocalVariableTypeTable_attribute.Entry entry, int pc);
67 public final String text;
68 }
69
70 static LocalVariableTypeTableWriter instance(Context context) {
71 LocalVariableTypeTableWriter instance = context.get(LocalVariableTypeTableWriter.class);
72 if (instance == null)
73 instance = new LocalVariableTypeTableWriter(context);
74 return instance;
75 }
76
77 protected LocalVariableTypeTableWriter(Context context) {
78 super(context);
79 context.put(LocalVariableTypeTableWriter.class, this);
80 classWriter = ClassWriter.instance(context);
81 }
82
83 public void reset(Code_attribute attr) {
84 codeAttr = attr;
85 pcMap = new HashMap<>();
86 LocalVariableTypeTable_attribute lvt =
87 (LocalVariableTypeTable_attribute) (attr.attributes.get(Attribute.LocalVariableTypeTable));
88 if (lvt == null)
89 return;
90
91 for (int i = 0; i < lvt.local_variable_table.length; i++) {
92 LocalVariableTypeTable_attribute.Entry entry = lvt.local_variable_table[i];
93 put(entry.start_pc, entry);
94 put(entry.start_pc + entry.length, entry);
95 }
96 }
97
98 public void writeDetails(Instruction instr) {
99 int pc = instr.getPC();
100 writeLocalVariables(pc, NoteKind.END);
101 writeLocalVariables(pc, NoteKind.START);
102 }
103
104 @Override
105 public void flush() {
106 int pc = codeAttr.code_length;
107 writeLocalVariables(pc, NoteKind.END);
108 }
109
110 public void writeLocalVariables(int pc, NoteKind kind) {
111 ConstantPool constant_pool = classWriter.getClassFile().constant_pool;
112 String indent = space(2); // get from Options?
113 List<LocalVariableTypeTable_attribute.Entry> entries = pcMap.get(pc);
114 if (entries != null) {
115 for (ListIterator<LocalVariableTypeTable_attribute.Entry> iter =
116 entries.listIterator(kind == NoteKind.END ? entries.size() : 0);
117 kind == NoteKind.END ? iter.hasPrevious() : iter.hasNext() ; ) {
118 LocalVariableTypeTable_attribute.Entry entry =
119 kind == NoteKind.END ? iter.previous() : iter.next();
120 if (kind.match(entry, pc)) {
121 print(indent);
122 print(kind.text);
123 print(" generic local ");
124 print(entry.index);
125 print(" // ");
126 Descriptor d = new Signature(entry.signature_index);
127 try {
128 print(d.getFieldType(constant_pool).toString().replace("/", "."));
129 } catch (InvalidDescriptor e) {
130 print(report(e));
131 } catch (ConstantPoolException e) {
132 print(report(e));
133 }
134 print(" ");
135 try {
136 print(constant_pool.getUTF8Value(entry.name_index));
137 } catch (ConstantPoolException e) {
138 print(report(e));
139 }
140 println();
141 }
142 }
143 }
144 }
145
146 private void put(int pc, LocalVariableTypeTable_attribute.Entry entry) {
147 List<LocalVariableTypeTable_attribute.Entry> list = pcMap.get(pc);
148 if (list == null) {
149 list = new ArrayList<>();
150 pcMap.put(pc, list);
151 }
152 if (!list.contains(entry))
153 list.add(entry);
154 }
155
156 private ClassWriter classWriter;
157 private Code_attribute codeAttr;
158 private Map<Integer, List<LocalVariableTypeTable_attribute.Entry>> pcMap;
159 }