ASM: a very small and fast Java bytecode manipulation framework
Copyright (c) 2000-2011 INRIA, France Telecom
All rights reserved.
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modification, are permitted provided that the following conditions
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   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
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SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
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THE POSSIBILITY OF SUCH DAMAGE.
/***
 * 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 org.objectweb.asm.signature;

import org.objectweb.asm.Opcodes;

A signature visitor that generates signatures in string format.
Author:
Thomas Hallgren, Eric Bruneton/**
 * A signature visitor that generates signatures in string format.
 * 
 * @author Thomas Hallgren
 * @author Eric Bruneton
 */
public class SignatureWriter extends SignatureVisitor {

    
Builder used to construct the signature.
/**
     * Builder used to construct the signature.
     */
    private final StringBuilder buf = new StringBuilder();

    
Indicates if the signature contains formal type parameters.
/**
     * Indicates if the signature contains formal type parameters.
     */
    private boolean hasFormals;

    
Indicates if the signature contains method parameter types.
/**
     * Indicates if the signature contains method parameter types.
     */
    private boolean hasParameters;

    
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.
/**
     * 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;

    
Constructs a new SignatureWriter object. /**
     * Constructs a new {@link SignatureWriter} object.
     */
    public SignatureWriter() {
        super(Opcodes.ASM5);
    }

    // ------------------------------------------------------------------------
    // Implementation of the SignatureVisitor interface
    // ------------------------------------------------------------------------

    @Override
    public void visitFormalTypeParameter(final String name) {
        if (!hasFormals) {
            hasFormals = true;
            buf.append('<');
        }
        buf.append(name);
        buf.append(':');
    }

    @Override
    public SignatureVisitor visitClassBound() {
        return this;
    }

    @Override
    public SignatureVisitor visitInterfaceBound() {
        buf.append(':');
        return this;
    }

    @Override
    public SignatureVisitor visitSuperclass() {
        endFormals();
        return this;
    }

    @Override
    public SignatureVisitor visitInterface() {
        return this;
    }

    @Override
    public SignatureVisitor visitParameterType() {
        endFormals();
        if (!hasParameters) {
            hasParameters = true;
            buf.append('(');
        }
        return this;
    }

    @Override
    public SignatureVisitor visitReturnType() {
        endFormals();
        if (!hasParameters) {
            buf.append('(');
        }
        buf.append(')');
        return this;
    }

    @Override
    public SignatureVisitor visitExceptionType() {
        buf.append('^');
        return this;
    }

    @Override
    public void visitBaseType(final char descriptor) {
        buf.append(descriptor);
    }

    @Override
    public void visitTypeVariable(final String name) {
        buf.append('T');
        buf.append(name);
        buf.append(';');
    }

    @Override
    public SignatureVisitor visitArrayType() {
        buf.append('[');
        return this;
    }

    @Override
    public void visitClassType(final String name) {
        buf.append('L');
        buf.append(name);
        argumentStack *= 2;
    }

    @Override
    public void visitInnerClassType(final String name) {
        endArguments();
        buf.append('.');
        buf.append(name);
        argumentStack *= 2;
    }

    @Override
    public void visitTypeArgument() {
        if (argumentStack % 2 == 0) {
            ++argumentStack;
            buf.append('<');
        }
        buf.append('*');
    }

    @Override
    public SignatureVisitor visitTypeArgument(final char wildcard) {
        if (argumentStack % 2 == 0) {
            ++argumentStack;
            buf.append('<');
        }
        if (wildcard != '=') {
            buf.append(wildcard);
        }
        return this;
    }

    @Override
    public void visitEnd() {
        endArguments();
        buf.append(';');
    }

    
Returns the signature that was built by this signature writer.
Returns:
the signature that was built by this signature writer./**
     * Returns the signature that was built by this signature writer.
     * 
     * @return the signature that was built by this signature writer.
     */
    @Override
    public String toString() {
        return buf.toString();
    }

    // ------------------------------------------------------------------------
    // Utility methods
    // ------------------------------------------------------------------------

    
Ends the formal type parameters section of the signature.
/**
     * Ends the formal type parameters section of the signature.
     */
    private void endFormals() {
        if (hasFormals) {
            hasFormals = false;
            buf.append('>');
        }
    }

    
Ends the type arguments of a class or inner class type.
/**
     * Ends the type arguments of a class or inner class type.
     */
    private void endArguments() {
        if (argumentStack % 2 != 0) {
            buf.append('>');
        }
        argumentStack /= 2;
    }
}