import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Dimension;
import java.awt.Font;
import java.awt.FontMetrics;
import java.awt.Graphics;
import java.awt.Rectangle;
import javax.swing.BorderFactory;
import javax.swing.JComponent;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
import javax.swing.JTextArea;

public class LineNumber extends JComponent {
	static final long serialVersionUID = 3679449495322768618L;
	private final static Color DEFAULT_BACKGROUND = new Color(230, 163, 4);
	private final static Color DEFAULT_FOREGROUND = Color.black;
	private final static Font DEFAULT_FONT = new Font("monospaced", Font.PLAIN,
			12);
	// LineNumber height (abends when I use MAX_VALUE)
	private final static int HEIGHT = Integer.MAX_VALUE - 1000000;
	// Set right/left margin
	private final static int MARGIN = 5;
	// Line height of this LineNumber component
	private int lineHeight;
	// Line height of this LineNumber component
	private int fontLineHeight;
	private int currentRowWidth;
	// Metrics of this LineNumber component
	private FontMetrics fontMetrics;

	/**
	 * Convenience constructor for Text Components
	 */
	public LineNumber(JComponent component) {
		if (component == null) {
			setBackground(DEFAULT_BACKGROUND);
			setForeground(DEFAULT_FOREGROUND);
			setFont(DEFAULT_FONT);
		} else {
			setBackground(DEFAULT_BACKGROUND);
			setForeground(component.getForeground());
			setFont(component.getFont());
		}
		setPreferredSize(9999);
	}

	public void setPreferredSize(int row) {
		int width = fontMetrics.stringWidth(String.valueOf(row));
		if (currentRowWidth < width) {
			currentRowWidth = width;
			setPreferredSize(new Dimension(2 * MARGIN + width, HEIGHT));
		}
	}

	public void setFont(Font font) {
		super.setFont(font);
		fontMetrics = getFontMetrics(getFont());
		fontLineHeight = fontMetrics.getHeight();
	}

	/**
	 * The line height defaults to the line height of the font for this
	 * component. The line height can be overridden by setting it to a positive
	 * non-zero value.
	 */
	public int getLineHeight() {
		if (lineHeight == 0)
			return fontLineHeight;
		else
			return lineHeight;
	}

	public void setLineHeight(int lineHeight) {
		if (lineHeight > 0)
			this.lineHeight = lineHeight;
	}

	public int getStartOffset() {
		return 4;
	}

	public void paintComponent(Graphics g) {
		int lineHeight = getLineHeight();
		int startOffset =
        
		

        		
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