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 * reserved comment block

 * DO NOT REMOVE OR ALTER!

 */

/*

 * Licensed to the Apache Software Foundation (ASF) under one or more

 * contributor license agreements.  See the NOTICE file distributed with

 * this work for additional information regarding copyright ownership.

 * The ASF licenses this file to You under the Apache License, Version 2.0

 * (the "License"); you may not use this file except in compliance with

 * the License.  You may obtain a copy of the License at

 *

 *      http://www.apache.org/licenses/LICENSE-2.0

 *

 * Unless required by applicable law or agreed to in writing, software

 * distributed under the License is distributed on an "AS IS" BASIS,

 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.

 * See the License for the specific language governing permissions and

 * limitations under the License.

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

import java.io.DataInput;

import java.io.DataOutputStream;

import java.io.IOException;

import com.sun.org.apache.bcel.internal.Const;

/**

 * This class represents colection of local variables in a

 * method. This attribute is contained in the <em>Code</em> attribute.

 *

 * @see     Code

 * @see LocalVariable

 */

public class LocalVariableTable extends Attribute {

    private LocalVariable[] local_variable_table; // variables

    /**

     * Initialize from another object. Note that both objects use the same

     * references (shallow copy). Use copy() for a physical copy.

     */

    public LocalVariableTable(final LocalVariableTable c) {

        this(c.getNameIndex(), c.getLength(), c.getLocalVariableTable(), c.getConstantPool());

    }

    /**

     * @param name_index Index in constant pool to `LocalVariableTable'

     * @param length Content length in bytes

     * @param local_variable_table Table of local variables

     * @param constant_pool Array of constants

     */

    public LocalVariableTable(final int name_index, final int length, final LocalVariable[] local_variable_table,

            final ConstantPool constant_pool) {

        super(Const.ATTR_LOCAL_VARIABLE_TABLE, name_index, length, constant_pool);

        this.local_variable_table = local_variable_table;

    }

    /**

     * Construct object from input stream.

     * @param name_index Index in constant pool

     * @param length Content length in bytes

     * @param input Input stream

     * @param constant_pool Array of constants

     * @throws IOException

     */

    LocalVariableTable(final int name_index, final int length, final DataInput input, final ConstantPool constant_pool)

            throws IOException {

        this(name_index, length, (LocalVariable[]) null, constant_pool);

        final int local_variable_table_length = input.readUnsignedShort();

        local_variable_table = new LocalVariable[local_variable_table_length];

        for (int i = 0; i < local_variable_table_length; i++) {

            local_variable_table[i] = new LocalVariable(input, constant_pool);

        }

    }

    /**

     * Called by objects that are traversing the nodes of the tree implicitely

     * defined by the contents of a Java class. I.e., the hierarchy of methods,

     * fields, attributes, etc. spawns a tree of objects.

     *

     * @param v Visitor object

     */

    @Override

    public void accept( final Visitor v ) {

        v.visitLocalVariableTable(this);

    }

    /**

     * Dump local variable table attribute to file stream in binary format.

     *

     * @param file Output file stream

     * @throws IOException

     */

    @Override

    public final void dump( final DataOutputStream file ) throws IOException {

        super.dump(file);

        file.writeShort(local_variable_table.length);

        for (final LocalVariable variable : local_variable_table) {

            variable.dump(file);

        }

    }

    /**

     * @return Array of local variables of method.

     */

    public final LocalVariable[] getLocalVariableTable() {

        return local_variable_table;

    }

    /**

     *

     * @param index the variable slot

     *

     * @return the first LocalVariable that matches the slot or null if not found

     *

     * @deprecated since 5.2 because multiple variables can share the

     *             same slot, use getLocalVariable(int index, int pc) instead.

     */

    @java.lang.Deprecated

    public final LocalVariable getLocalVariable( final int index ) {

        for (final LocalVariable variable : local_variable_table) {

            if (variable.getIndex() == index) {

                return variable;

            }

        }

        return null;

    }

    /**

     *

     * @param index the variable slot

     * @param pc the current pc that this variable is alive

     *

     * @return the LocalVariable that matches or null if not found

     */

    public final LocalVariable getLocalVariable( final int index, final int pc ) {

        for (final LocalVariable variable : local_variable_table) {

            if (variable.getIndex() == index) {

                final int start_pc = variable.getStartPC();

                final int end_pc = start_pc + variable.getLength();

                if ((pc >= start_pc) && (pc <= end_pc)) {

                    return variable;

                }

            }

        }

        return null;

    }

    public final void setLocalVariableTable( final LocalVariable[] local_variable_table ) {

        this.local_variable_table = local_variable_table;

    }

    /**

     * @return String representation.

     */

    @Override

    public final String toString() {

        final StringBuilder buf = new StringBuilder();

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

            buf.append(local_variable_table[i]);

            if (i < local_variable_table.length - 1) {

                buf.append('\n');

            }

        }

        return buf.toString();

    }

    /**

     * @return deep copy of this attribute

     */

    @Override

    public Attribute copy( final ConstantPool _constant_pool ) {

        final LocalVariableTable c = (LocalVariableTable) clone();

        c.local_variable_table = new LocalVariable[local_variable_table.length];

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

            c.local_variable_table[i] = local_variable_table[i].copy();

        }

        c.setConstantPool(_constant_pool);

        return c;

    }

    public final int getTableLength() {

        return local_variable_table == null ? 0 : local_variable_table.length;

    }

}