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 * Copyright (c) 2011 Google
34 * All rights reserved.
35 *
36 * Redistribution and use in source and binary forms, with or without
37 * modification, are permitted provided that the following conditions
38 * are met:
39 * 1. Redistributions of source code must retain the above copyright
40 * notice, this list of conditions and the following disclaimer.
41 * 2. Redistributions in binary form must reproduce the above copyright
42 * notice, this list of conditions and the following disclaimer in the
43 * documentation and/or other materials provided with the distribution.
44 * 3. Neither the name of the copyright holders nor the names of its
45 * contributors may be used to endorse or promote products derived from
46 * this software without specific prior written permission.
47 *
48 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
49 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
50 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
51 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
52 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
53 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
54 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
55 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
56 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
57 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
58 * THE POSSIBILITY OF SUCH DAMAGE.
59 */
60 package jdk.internal.org.objectweb.asm.util;
61
62 import java.io.PrintWriter;
63
64 import jdk.internal.org.objectweb.asm.AnnotationVisitor;
65 import jdk.internal.org.objectweb.asm.Attribute;
66 import jdk.internal.org.objectweb.asm.ClassVisitor;
67 import jdk.internal.org.objectweb.asm.FieldVisitor;
68 import jdk.internal.org.objectweb.asm.MethodVisitor;
69 import jdk.internal.org.objectweb.asm.Opcodes;
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. <p> The trace printed when
76 * visiting the <tt>Hello</tt> class is the following: <p> <blockquote>
77 *
78 * <pre> // class version 49.0 (49) // access flags 0x21 public class Hello {
79 *
80 * // compiled from: Hello.java
81 *
82 * // access flags 0x1 public <init> ()V ALOAD 0 INVOKESPECIAL
83 * java/lang/Object <init> ()V RETURN MAXSTACK = 1 MAXLOCALS = 1
84 *
85 * // access flags 0x9 public static main ([Ljava/lang/String;)V GETSTATIC
86 * java/lang/System out Ljava/io/PrintStream; LDC "hello"
87 * INVOKEVIRTUAL java/io/PrintStream println (Ljava/lang/String;)V RETURN
88 * MAXSTACK = 2 MAXLOCALS = 1 } </pre>
89 *
90 * </blockquote> where <tt>Hello</tt> is defined by: <p> <blockquote>
91 *
92 * <pre> public class Hello {
93 *
94 * public static void main(String[] args) {
95 * System.out.println("hello"); } } </pre>
96 *
97 * </blockquote>
98 *
99 * @author Eric Bruneton
100 * @author Eugene Kuleshov
101 */
102 public final class TraceClassVisitor extends ClassVisitor {
103
104 /**
105 * The print writer to be used to print the class. May be null.
106 */
107 private final PrintWriter pw;
108
109 /**
110 * The object that actually converts visit events into text.
111 */
112 public final Printer p;
113
114 /**
115 * Constructs a new {@link TraceClassVisitor}.
116 *
117 * @param pw the print writer to be used to print the class.
118 */
119 public TraceClassVisitor(final PrintWriter pw) {
120 this(null, pw);
121 }
122
123 /**
124 * Constructs a new {@link TraceClassVisitor}.
125 *
126 * @param cv the {@link ClassVisitor} to which this visitor delegates calls.
127 * May be <tt>null</tt>.
128 * @param pw the print writer to be used to print the class.
129 */
130 public TraceClassVisitor(final ClassVisitor cv, final PrintWriter pw) {
131 this(cv, new Textifier(), pw);
132 }
133
134 /**
135 * Constructs a new {@link TraceClassVisitor}.
136 *
137 * @param cv the {@link ClassVisitor} to which this visitor delegates calls.
138 * May be <tt>null</tt>.
139 * @param p the object that actually converts visit events into text.
140 * @param pw the print writer to be used to print the class. May be null if
141 * you simply want to use the result via
142 * {@link Printer#getText()}, instead of printing it.
143 */
144 public TraceClassVisitor(
145 final ClassVisitor cv,
146 final Printer p,
147 final PrintWriter pw)
148 {
149 super(Opcodes.ASM4, cv);
150 this.pw = pw;
151 this.p = p;
152 }
153
154 @Override
155 public void visit(
156 final int version,
157 final int access,
158 final String name,
159 final String signature,
160 final String superName,
161 final String[] interfaces)
162 {
163 p.visit(version, access, name, signature, superName, interfaces);
164 super.visit(version, access, name, signature, superName, interfaces);
165 }
166
167 @Override
168 public void visitSource(final String file, final String debug) {
169 p.visitSource(file, debug);
170 super.visitSource(file, debug);
171 }
172
173 @Override
174 public void visitOuterClass(
175 final String owner,
176 final String name,
177 final String desc)
178 {
179 p.visitOuterClass(owner, name, desc);
180 super.visitOuterClass(owner, name, desc);
181 }
182
183 @Override
184 public AnnotationVisitor visitAnnotation(
185 final String desc,
186 final boolean visible)
187 {
188 Printer p = this.p.visitClassAnnotation(desc, visible);
189 AnnotationVisitor av = cv == null ? null : cv.visitAnnotation(desc,
190 visible);
191 return new TraceAnnotationVisitor(av, p);
192 }
193
194 @Override
195 public void visitAttribute(final Attribute attr) {
196 p.visitClassAttribute(attr);
197 super.visitAttribute(attr);
198 }
199
200 @Override
201 public void visitInnerClass(
202 final String name,
203 final String outerName,
204 final String innerName,
205 final int access)
206 {
207 p.visitInnerClass(name, outerName, innerName, access);
208 super.visitInnerClass(name, outerName, innerName, access);
209 }
210
211 @Override
212 public FieldVisitor visitField(
213 final int access,
214 final String name,
215 final String desc,
216 final String signature,
217 final Object value)
218 {
219 Printer p = this.p.visitField(access,
220 name,
221 desc,
222 signature,
223 value);
224 FieldVisitor fv = cv == null ? null : cv.visitField(access,
225 name,
226 desc,
227 signature,
228 value);
229 return new TraceFieldVisitor(fv, p);
230 }
231
232 @Override
233 public MethodVisitor visitMethod(
234 final int access,
235 final String name,
236 final String desc,
237 final String signature,
238 final String[] exceptions)
239 {
240 Printer p = this.p.visitMethod(access,
241 name,
242 desc,
243 signature,
244 exceptions);
245 MethodVisitor mv = cv == null ? null : cv.visitMethod(access,
246 name,
247 desc,
248 signature,
249 exceptions);
250 return new TraceMethodVisitor(mv, p);
251 }
252
253 @Override
254 public void visitEnd() {
255 p.visitClassEnd();
256 if (pw != null) {
257 p.print(pw);
258 pw.flush();
259 }
260 super.visitEnd();
261 }
262 }