/*

 * reserved comment block

 * DO NOT REMOVE OR ALTER!

 */

package com.sun.org.apache.bcel.internal.classfile;

/* ====================================================================

 * The Apache Software License, Version 1.1

 *

 * Copyright (c) 2001 The Apache Software Foundation.  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. The end-user documentation included with the redistribution,

 *    if any, must include the following acknowledgment:

 *       "This product includes software developed by the

 *        Apache Software Foundation (http://www.apache.org/)."

 *    Alternately, this acknowledgment may appear in the software itself,

 *    if and wherever such third-party acknowledgments normally appear.

 *

 * 4. The names "Apache" and "Apache Software Foundation" and

 *    "Apache BCEL" must not be used to endorse or promote products

 *    derived from this software without prior written permission. For

 *    written permission, please contact apache@apache.org.

 *

 * 5. Products derived from this software may not be called "Apache",

 *    "Apache BCEL", nor may "Apache" appear in their name, without

 *    prior written permission of the Apache Software Foundation.

 *

 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED 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 APACHE SOFTWARE FOUNDATION OR

 * ITS 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

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 * 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.

 * ====================================================================

 *

 * This software consists of voluntary contributions made by many

 * individuals on behalf of the Apache Software Foundation.  For more

 * information on the Apache Software Foundation, please see

 * <http://www.apache.org/>.

 */

import java.util.Stack;

/**

 * Traverses a JavaClass with another Visitor object 'piggy-backed'

 * that is applied to all components of a JavaClass object. I.e. this

 * class supplies the traversal strategy, other classes can make use

 * of it.

 *

 * @author <A HREF="mailto:markus.dahm@berlin.de">M. Dahm</A>

 */

public class DescendingVisitor implements Visitor {

  private JavaClass clazz;

  private Visitor   visitor;

  private Stack     stack = new Stack();

  /** @return container of current entitity, i.e., predecessor during traversal

   */

  public Object predecessor() {

    return predecessor(0);

  }

  /**

   * @param level nesting level, i.e., 0 returns the direct predecessor

   * @return container of current entitity, i.e., predecessor during traversal

   */

  public Object predecessor(int level) {

    int size = stack.size();

    if((size < 2) || (level < 0))

      return null;

    else

      return stack.elementAt(size - (level + 2)); // size - 1 == current

  }

  /** @return current object

   */

  public Object current() {

    return stack.peek();

  }

  /**

   * @param clazz Class to traverse

   * @param visitor visitor object to apply to all components

   */

  public DescendingVisitor(JavaClass clazz, Visitor visitor) {

    this.clazz   = clazz;

    this.visitor = visitor;

  }

  /**

   * Start traversal.

   */

  public void visit() { clazz.accept(this); }

  public void visitJavaClass(JavaClass clazz) {

    stack.push(clazz);

    clazz.accept(visitor);

    Field[] fields = clazz.getFields();

    for(int i=0; i < fields.length; i++)

      fields[i].accept(this);

    Method[] methods = clazz.getMethods();

    for(int i=0; i < methods.length; i++)

      methods[i].accept(this);

    Attribute[] attributes = clazz.getAttributes();

    for(int i=0; i < attributes.length; i++)

      attributes[i].accept(this);

    clazz.getConstantPool().accept(this);

    stack.pop();

  }

  public void visitField(Field field) {

    stack.push(field);

    field.accept(visitor);

    Attribute[] attributes = field.getAttributes();

    for(int i=0; i < attributes.length; i++)

      attributes[i].accept(this);

    stack.pop();

  }

  public void visitConstantValue(ConstantValue cv) {

    stack.push(cv);

    cv.accept(visitor);

    stack.pop();

  }

  public void visitMethod(Method method) {

    stack.push(method);

    method.accept(visitor);

    Attribute[] attributes = method.getAttributes();

    for(int i=0; i < attributes.length; i++)

      attributes[i].accept(this);

    stack.pop();

  }

  public void visitExceptionTable(ExceptionTable table) {

    stack.push(table);

    table.accept(visitor);

    stack.pop();

  }

  public void visitCode(Code code) {

    stack.push(code);

    code.accept(visitor);

    CodeException[] table = code.getExceptionTable();

    for(int i=0; i < table.length; i++)

      table[i].accept(this);

    Attribute[] attributes = code.getAttributes();

    for(int i=0; i < attributes.length; i++)

      attributes[i].accept(this);

    stack.pop();

  }

  public void visitCodeException(CodeException ce) {

    stack.push(ce);

    ce.accept(visitor);

    stack.pop();

  }

  public void visitLineNumberTable(LineNumberTable table) {

    stack.push(table);

    table.accept(visitor);

    LineNumber[] numbers = table.getLineNumberTable();

    for(int i=0; i < numbers.length; i++)

      numbers[i].accept(this);

    stack.pop();

  }

  public void visitLineNumber(LineNumber number) {

    stack.push(number);

    number.accept(visitor);

    stack.pop();

  }

  public void visitLocalVariableTable(LocalVariableTable table) {

    stack.push(table);

    table.accept(visitor);

    LocalVariable[] vars = table.getLocalVariableTable();

    for(int i=0; i < vars.length; i++)

      vars[i].accept(this);

    stack.pop();

  }

  public void visitStackMap(StackMap table) {

    stack.push(table);

    table.accept(visitor);

    StackMapEntry[] vars = table.getStackMap();

    for(int i=0; i < vars.length; i++)

      vars[i].accept(this);

    stack.pop();

  }

  public void visitStackMapEntry(StackMapEntry var) {

    stack.push(var);

    var.accept(visitor);

    stack.pop();

  }

  public void visitLocalVariable(LocalVariable var) {

    stack.push(var);

    var.accept(visitor);

    stack.pop();

  }

  public void visitConstantPool(ConstantPool cp) {

    stack.push(cp);

    cp.accept(visitor);

    Constant[] constants = cp.getConstantPool();

    for(int i=1; i < constants.length; i++) {

      if(constants[i] != null)

        constants[i].accept(this);

    }

    stack.pop();

  }

  public void visitConstantClass(ConstantClass constant) {

    stack.push(constant);

    constant.accept(visitor);

    stack.pop();

  }

  public void visitConstantDouble(ConstantDouble constant) {

    stack.push(constant);

    constant.accept(visitor);

    stack.pop();

  }

  public void visitConstantFieldref(ConstantFieldref constant) {

    stack.push(constant);

    constant.accept(visitor);

    stack.pop();

  }

  public void visitConstantFloat(ConstantFloat constant) {

    stack.push(constant);

    constant.accept(visitor);

    stack.pop();

 }

  public void visitConstantInteger(ConstantInteger constant) {

    stack.push(constant);

    constant.accept(visitor);

    stack.pop();

  }

  public void visitConstantInterfaceMethodref(ConstantInterfaceMethodref constant) {

    stack.push(constant);

    constant.accept(visitor);

    stack.pop();

  }

  public void visitConstantLong(ConstantLong constant) {

    stack.push(constant);

    constant.accept(visitor);

    stack.pop();

  }

  public void visitConstantMethodref(ConstantMethodref constant) {

    stack.push(constant);

    constant.accept(visitor);

    stack.pop();

  }

  public void visitConstantNameAndType(ConstantNameAndType constant) {

    stack.push(constant);

    constant.accept(visitor);

    stack.pop();

  }

  public void visitConstantString(ConstantString constant) {

    stack.push(constant);

    constant.accept(visitor);

    stack.pop();

  }

  public void visitConstantUtf8(ConstantUtf8 constant) {

    stack.push(constant);

    constant.accept(visitor);

    stack.pop();

  }

  public void visitInnerClasses(InnerClasses ic) {

    stack.push(ic);

    ic.accept(visitor);

    InnerClass[] ics = ic.getInnerClasses();

    for(int i=0; i < ics.length; i++)

      ics[i].accept(this);

    stack.pop();

  }

  public void visitInnerClass(InnerClass inner) {

    stack.push(inner);

    inner.accept(visitor);

    stack.pop();

  }

  public void visitDeprecated(Deprecated attribute) {

    stack.push(attribute);

    attribute.accept(visitor);

    stack.pop();

  }

  public void visitSignature(Signature attribute) {

    stack.push(attribute);

    attribute.accept(visitor);

    stack.pop();

  }

  public void visitSourceFile(SourceFile attribute) {

    stack.push(attribute);

    attribute.accept(visitor);

    stack.pop();

  }

  public void visitSynthetic(Synthetic attribute) {

    stack.push(attribute);

    attribute.accept(visitor);

    stack.pop();

  }

  public void visitUnknown(Unknown attribute) {

    stack.push(attribute);

    attribute.accept(visitor);

    stack.pop();

 }

}