1 /*
2 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
3 *
4 * This code is free software; you can redistribute it and/or modify it
5 * under the terms of the GNU General Public License version 2 only, as
6 * published by the Free Software Foundation. Oracle designates this
7 * particular file as subject to the "Classpath" exception as provided
8 * by Oracle in the LICENSE file that accompanied this code.
9 *
10 * This code is distributed in the hope that it will be useful, but WITHOUT
11 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
12 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
13 * version 2 for more details (a copy is included in the LICENSE file that
14 * accompanied this code).
15 *
16 * You should have received a copy of the GNU General Public License version
17 * 2 along with this work; if not, write to the Free Software Foundation,
18 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
19 *
20 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
21 * or visit www.oracle.com if you need additional information or have any
22 * questions.
23 */
24
25 /*
26 * This file is available under and governed by the GNU General Public
27 * License version 2 only, as published by the Free Software Foundation.
28 * However, the following notice accompanied the original version of this
29 * file:
30 *
31 * ASM: a very small and fast Java bytecode manipulation framework
32 * Copyright (c) 2000-2011 INRIA, France Telecom
33 * All rights reserved.
34 *
35 * Redistribution and use in source and binary forms, with or without
36 * modification, are permitted provided that the following conditions
37 * are met:
38 * 1. Redistributions of source code must retain the above copyright
39 * notice, this list of conditions and the following disclaimer.
40 * 2. Redistributions in binary form must reproduce the above copyright
41 * notice, this list of conditions and the following disclaimer in the
42 * documentation and/or other materials provided with the distribution.
43 * 3. Neither the name of the copyright holders nor the names of its
44 * contributors may be used to endorse or promote products derived from
45 * this software without specific prior written permission.
46 *
47 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
48 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
49 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
50 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
51 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
52 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
53 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
54 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
55 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
56 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
57 * THE POSSIBILITY OF SUCH DAMAGE.
58 */
59 package jdk.internal.org.objectweb.asm.util;
60
61 import java.io.PrintWriter;
62
63 import jdk.internal.org.objectweb.asm.AnnotationVisitor;
64 import jdk.internal.org.objectweb.asm.Attribute;
65 import jdk.internal.org.objectweb.asm.ClassVisitor;
66 import jdk.internal.org.objectweb.asm.FieldVisitor;
67 import jdk.internal.org.objectweb.asm.MethodVisitor;
68 import jdk.internal.org.objectweb.asm.Opcodes;
69 import jdk.internal.org.objectweb.asm.TypePath;
70
71 /**
72 * A {@link ClassVisitor} that prints the classes it visits with a
73 * {@link Printer}. This class visitor can be used in the middle of a class
74 * visitor chain to trace the class that is visited at a given point in this
75 * chain. This may be useful for debugging purposes.
76 * <p>
77 * The trace printed when visiting the <tt>Hello</tt> class is the following:
78 * <p>
79 * <blockquote>
80 *
81 * <pre>
82 * // class version 49.0 (49) // access flags 0x21 public class Hello {
83 *
84 * // compiled from: Hello.java
85 *
86 * // access flags 0x1 public <init> ()V ALOAD 0 INVOKESPECIAL
87 * java/lang/Object <init> ()V RETURN MAXSTACK = 1 MAXLOCALS = 1
88 *
89 * // access flags 0x9 public static main ([Ljava/lang/String;)V GETSTATIC
90 * java/lang/System out Ljava/io/PrintStream; LDC "hello"
91 * INVOKEVIRTUAL java/io/PrintStream println (Ljava/lang/String;)V RETURN
92 * MAXSTACK = 2 MAXLOCALS = 1 }
93 * </pre>
94 *
95 * </blockquote> where <tt>Hello</tt> is defined by:
96 * <p>
97 * <blockquote>
98 *
99 * <pre>
100 * public class Hello {
101 *
102 * public static void main(String[] args) {
103 * System.out.println("hello");
104 * }
105 * }
106 * </pre>
107 *
108 * </blockquote>
109 *
110 * @author Eric Bruneton
111 * @author Eugene Kuleshov
112 */
113 public final class TraceClassVisitor extends ClassVisitor {
114
115 /**
116 * The print writer to be used to print the class. May be null.
117 */
118 private final PrintWriter pw;
119
120 /**
121 * The object that actually converts visit events into text.
122 */
123 public final Printer p;
124
125 /**
126 * Constructs a new {@link TraceClassVisitor}.
127 *
128 * @param pw
129 * the print writer to be used to print the class.
130 */
131 public TraceClassVisitor(final PrintWriter pw) {
132 this(null, pw);
133 }
134
135 /**
136 * Constructs a new {@link TraceClassVisitor}.
137 *
138 * @param cv
139 * the {@link ClassVisitor} to which this visitor delegates
140 * calls. May be <tt>null</tt>.
141 * @param pw
142 * the print writer to be used to print the class.
143 */
144 public TraceClassVisitor(final ClassVisitor cv, final PrintWriter pw) {
145 this(cv, new Textifier(), pw);
146 }
147
148 /**
149 * Constructs a new {@link TraceClassVisitor}.
150 *
151 * @param cv
152 * the {@link ClassVisitor} to which this visitor delegates
153 * calls. May be <tt>null</tt>.
154 * @param p
155 * the object that actually converts visit events into text.
156 * @param pw
157 * the print writer to be used to print the class. May be null if
158 * you simply want to use the result via
159 * {@link Printer#getText()}, instead of printing it.
160 */
161 public TraceClassVisitor(final ClassVisitor cv, final Printer p,
162 final PrintWriter pw) {
163 super(Opcodes.ASM5, cv);
164 this.pw = pw;
165 this.p = p;
166 }
167
168 @Override
169 public void visit(final int version, final int access, final String name,
170 final String signature, final String superName,
171 final String[] interfaces) {
172 p.visit(version, access, name, signature, superName, interfaces);
173 super.visit(version, access, name, signature, superName, interfaces);
174 }
175
176 @Override
177 public void visitSource(final String file, final String debug) {
178 p.visitSource(file, debug);
179 super.visitSource(file, debug);
180 }
181
182 @Override
183 public void visitOuterClass(final String owner, final String name,
184 final String desc) {
185 p.visitOuterClass(owner, name, desc);
186 super.visitOuterClass(owner, name, desc);
187 }
188
189 @Override
190 public AnnotationVisitor visitAnnotation(final String desc,
191 final boolean visible) {
192 Printer p = this.p.visitClassAnnotation(desc, visible);
193 AnnotationVisitor av = cv == null ? null : cv.visitAnnotation(desc,
194 visible);
195 return new TraceAnnotationVisitor(av, p);
196 }
197
198 @Override
199 public AnnotationVisitor visitTypeAnnotation(int typeRef,
200 TypePath typePath, String desc, boolean visible) {
201 Printer p = this.p.visitClassTypeAnnotation(typeRef, typePath, desc,
202 visible);
203 AnnotationVisitor av = cv == null ? null : cv.visitTypeAnnotation(
204 typeRef, typePath, desc, visible);
205 return new TraceAnnotationVisitor(av, p);
206 }
207
208 @Override
209 public void visitAttribute(final Attribute attr) {
210 p.visitClassAttribute(attr);
211 super.visitAttribute(attr);
212 }
213
214 @Override
215 public void visitInnerClass(final String name, final String outerName,
216 final String innerName, final int access) {
217 p.visitInnerClass(name, outerName, innerName, access);
218 super.visitInnerClass(name, outerName, innerName, access);
219 }
220
221 @Override
222 public FieldVisitor visitField(final int access, final String name,
223 final String desc, final String signature, final Object value) {
224 Printer p = this.p.visitField(access, name, desc, signature, value);
225 FieldVisitor fv = cv == null ? null : cv.visitField(access, name, desc,
226 signature, value);
227 return new TraceFieldVisitor(fv, p);
228 }
229
230 @Override
231 public MethodVisitor visitMethod(final int access, final String name,
232 final String desc, final String signature, final String[] exceptions) {
233 Printer p = this.p.visitMethod(access, name, desc, signature,
234 exceptions);
235 MethodVisitor mv = cv == null ? null : cv.visitMethod(access, name,
236 desc, signature, exceptions);
237 return new TraceMethodVisitor(mv, p);
238 }
239
240 @Override
241 public void visitEnd() {
242 p.visitClassEnd();
243 if (pw != null) {
244 p.print(pw);
245 pw.flush();
246 }
247 super.visitEnd();
248 }
249 }