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

 * @version $Id: LineNumberGen.java 1749603 2016-06-21 20:50:19Z ggregory $

public class LineNumberGen implements InstructionTargeter, Cloneable {

    private InstructionHandle ih;

    private int src_line;

    /**

     * 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(), src_line);

    }

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

        if (ih == null) {

            throw new NullPointerException("InstructionHandle may not be null");

        }

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

        this.ih = ih;

    }

    @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.src_line = src_line;

    public int getSourceLine() {

        return src_line;

    }