Back to index...

	/*
	* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
	*
	* This code is free software; you can redistribute it and/or modify it
	* under the terms of the GNU General Public License version 2 only, as
	* published by the Free Software Foundation. Oracle designates this
	* particular file as subject to the "Classpath" exception as provided
	* by Oracle in the LICENSE file that accompanied this code.
	*
	* This code is distributed in the hope that it will be useful, but WITHOUT
	* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
	* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
	* version 2 for more details (a copy is included in the LICENSE file that
	* accompanied this code).
	*
	* You should have received a copy of the GNU General Public License version
	* 2 along with this work; if not, write to the Free Software Foundation,
	* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
	*
	* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
	* or visit www.oracle.com if you need additional information or have any
	* questions.
	*/

	/*
	* This file is available under and governed by the GNU General Public
	* License version 2 only, as published by the Free Software Foundation.
	* However, the following notice accompanied the original version of this
	* file:
	*
	* ASM: a very small and fast Java bytecode manipulation framework
	* Copyright (c) 2000-2011 INRIA, France Telecom
	* All rights reserved.
	*
	* Redistribution and use in source and binary forms, with or without
	* modification, are permitted provided that the following conditions
	* are met:
	* 1. Redistributions of source code must retain the above copyright
	* notice, this list of conditions and the following disclaimer.
	* 2. Redistributions in binary form must reproduce the above copyright
	* notice, this list of conditions and the following disclaimer in the
	* documentation and/or other materials provided with the distribution.
	* 3. Neither the name of the copyright holders nor the names of its
	* contributors may be used to endorse or promote products derived from
	* this software without specific prior written permission.
	*
	* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
	* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
	* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
	* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
	* LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
	* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
	* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
	* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
	* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
	* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
	* THE POSSIBILITY OF SUCH DAMAGE.
	*/
	package jdk.internal.org.objectweb.asm.util;

	import jdk.internal.org.objectweb.asm.Opcodes;
	import jdk.internal.org.objectweb.asm.signature.SignatureVisitor;

	/**
	* A {@link SignatureVisitor} that prints a disassembled view of the signature
	* it visits.
	*
	* @author Eugene Kuleshov
	* @author Eric Bruneton
	*/
	public final class TraceSignatureVisitor extends SignatureVisitor {

	private final StringBuilder declaration;

	private boolean isInterface;

	private boolean seenFormalParameter;

	private boolean seenInterfaceBound;

	private boolean seenParameter;

	private boolean seenInterface;

	private StringBuilder returnType;

	private StringBuilder exceptions;

	/**
	* Stack used to keep track of class types that have arguments. Each element
	* of this stack is a boolean encoded in one bit. The top of the stack is
	* the lowest order bit. Pushing false = 2, pushing true = 2+1, popping =
	* /2.
	*/
	private int argumentStack;

	/**
	* Stack used to keep track of array class types. Each element of this stack
	* is a boolean encoded in one bit. The top of the stack is the lowest order
	* bit. Pushing false = 2, pushing true = 2+1, popping = /2.
	*/
	private int arrayStack;

	private String separator = "";

	public TraceSignatureVisitor(final int access) {
	super(Opcodes.ASM6);
	isInterface = (access & Opcodes.ACC_INTERFACE) != 0;
	this.declaration = new StringBuilder();
	}

	private TraceSignatureVisitor(final StringBuilder buf) {
	super(Opcodes.ASM6);
	this.declaration = buf;
	}

	@Override
	public void visitFormalTypeParameter(final String name) {
	declaration.append(seenFormalParameter ? ", " : "<").append(name);
	seenFormalParameter = true;
	seenInterfaceBound = false;
	}

	@Override
	public SignatureVisitor visitClassBound() {
	separator = " extends ";
	startType();
	return this;
	}

	@Override
	public SignatureVisitor visitInterfaceBound() {
	separator = seenInterfaceBound ? ", " : " extends ";
	seenInterfaceBound = true;
	startType();
	return this;
	}

	@Override
	public SignatureVisitor visitSuperclass() {
	endFormals();
	separator = " extends ";
	startType();
	return this;
	}

	@Override
	public SignatureVisitor visitInterface() {
	separator = seenInterface ? ", " : isInterface ? " extends "
	: " implements ";
	seenInterface = true;
	startType();
	return this;
	}

	@Override
	public SignatureVisitor visitParameterType() {
	endFormals();
	if (seenParameter) {
	declaration.append(", ");
	} else {
	seenParameter = true;
	declaration.append('(');
	}
	startType();
	return this;
	}

	@Override
	public SignatureVisitor visitReturnType() {
	endFormals();
	if (seenParameter) {
	seenParameter = false;
	} else {
	declaration.append('(');
	}
	declaration.append(')');
	returnType = new StringBuilder();
	return new TraceSignatureVisitor(returnType);
	}

	@Override
	public SignatureVisitor visitExceptionType() {
	if (exceptions == null) {
	exceptions = new StringBuilder();
	} else {
	exceptions.append(", ");
	}
	// startType();
	return new TraceSignatureVisitor(exceptions);
	}

	@Override
	public void visitBaseType(final char descriptor) {
	switch (descriptor) {
	case 'V':
	declaration.append("void");
	break;
	case 'B':
	declaration.append("byte");
	break;
	case 'J':
	declaration.append("long");
	break;
	case 'Z':
	declaration.append("boolean");
	break;
	case 'I':
	declaration.append("int");
	break;
	case 'S':
	declaration.append("short");
	break;
	case 'C':
	declaration.append("char");
	break;
	case 'F':
	declaration.append("float");
	break;
	// case 'D':
	default:
	declaration.append("double");
	break;
	}
	endType();
	}

	@Override
	public void visitTypeVariable(final String name) {
	declaration.append(name);
	endType();
	}

	@Override
	public SignatureVisitor visitArrayType() {
	startType();
	arrayStack \|= 1;
	return this;
	}

	@Override
	public void visitClassType(final String name) {
	if ("java/lang/Object".equals(name)) {
	// Map<java.lang.Object,java.util.List>
	// or
	// abstract public V get(Object key); (seen in Dictionary.class)
	// should have Object
	// but java.lang.String extends java.lang.Object is unnecessary
	boolean needObjectClass = argumentStack % 2 != 0 \|\| seenParameter;
	if (needObjectClass) {
	declaration.append(separator).append(name.replace('/', '.'));
	}
	} else {
	declaration.append(separator).append(name.replace('/', '.'));
	}
	separator = "";
	argumentStack *= 2;
	}

	@Override
	public void visitInnerClassType(final String name) {
	if (argumentStack % 2 != 0) {
	declaration.append('>');
	}
	argumentStack /= 2;
	declaration.append('.');
	declaration.append(separator).append(name.replace('/', '.'));
	separator = "";
	argumentStack *= 2;
	}

	@Override
	public void visitTypeArgument() {
	if (argumentStack % 2 == 0) {
	++argumentStack;
	declaration.append('<');
	} else {
	declaration.append(", ");
	}
	declaration.append('?');
	}

	@Override
	public SignatureVisitor visitTypeArgument(final char tag) {
	if (argumentStack % 2 == 0) {
	++argumentStack;
	declaration.append('<');
	} else {
	declaration.append(", ");
	}

	if (tag == EXTENDS) {
	declaration.append("? extends ");
	} else if (tag == SUPER) {
	declaration.append("? super ");
	}

	startType();
	return this;
	}

	@Override
	public void visitEnd() {
	if (argumentStack % 2 != 0) {
	declaration.append('>');
	}
	argumentStack /= 2;
	endType();
	}

	public String getDeclaration() {
	return declaration.toString();
	}

	public String getReturnType() {
	return returnType == null ? null : returnType.toString();
	}

	public String getExceptions() {
	return exceptions == null ? null : exceptions.toString();
	}

	// -----------------------------------------------

	private void endFormals() {
	if (seenFormalParameter) {
	declaration.append('>');
	seenFormalParameter = false;
	}
	}

	private void startType() {
	arrayStack *= 2;
	}

	private void endType() {
	if (arrayStack % 2 == 0) {
	arrayStack /= 2;
	} else {
	while (arrayStack % 2 != 0) {
	arrayStack /= 2;
	declaration.append("[]");
	}
	}
	}
	}

Back to index...