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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.

 */

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

import java.util.Objects;

import com.sun.org.apache.bcel.internal.classfile.LineNumber;

/**

 * This class represents a line number within a method, i.e., give an instruction

 * a line number corresponding to the source code line.

 *

 * @see     LineNumber

 * @see     MethodGen

 */

public class LineNumberGen implements InstructionTargeter, Cloneable {

    private InstructionHandle ih;

    private int srcLine;

    /**

     * Create a line number.

     *

     * @param ih instruction handle to reference

     */

    public LineNumberGen(final InstructionHandle ih, final int src_line) {

        setInstruction(ih);

        setSourceLine(src_line);

    }

    /**

     * @return true, if ih is target of this line number

     */

    @Override

    public boolean containsTarget( final InstructionHandle ih ) {

        return this.ih == ih;

    }

    /**

     * @param old_ih old target

     * @param new_ih new target

     */

    @Override

    public void updateTarget( final InstructionHandle old_ih, final InstructionHandle new_ih ) {

        if (old_ih != ih) {

            throw new ClassGenException("Not targeting " + old_ih + ", but " + ih + "}");

        }

        setInstruction(new_ih);

    }

    /**

     * Get LineNumber attribute .

     *

     * This relies on that the instruction list has already been dumped to byte code or

     * or that the `setPositions' methods has been called for the instruction list.

     */

    public LineNumber getLineNumber() {

        return new LineNumber(ih.getPosition(), srcLine);

    }

    public void setInstruction( final InstructionHandle instructionHandle ) { // TODO could be package-protected?

        Objects.requireNonNull(instructionHandle, "instructionHandle");

        BranchInstruction.notifyTarget(this.ih, instructionHandle, this);

        this.ih = instructionHandle;

    }

    @Override

    public Object clone() {

        try {

            return super.clone();

        } catch (final CloneNotSupportedException e) {

            throw new Error("Clone Not Supported"); // never happens

        }

    }

    public InstructionHandle getInstruction() {

        return ih;

    }

    public void setSourceLine( final int src_line ) { // TODO could be package-protected?

        this.srcLine = src_line;

    }

    public int getSourceLine() {

        return srcLine;

    }

}