import java.io.*;
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import javax.swing.tree.*;
import javax.swing.plaf.ColorUIResource;

public class CheckRenderer extends JPanel implements TreeCellRenderer {
    
    protected JCheckBox check;
    protected TreeLabel label;
    
    public CheckRenderer() {
        setLayout(null);
        add(check = new JCheckBox());
        add(label = new TreeLabel());
        check.setBackground(UIManager.getColor("Tree.textBackground"));
        label.setForeground(UIManager.getColor("Tree.textForeground"));
    }
    
    public Component getTreeCellRendererComponent(JTree tree, Object value,
        boolean isSelected, boolean expanded,
        boolean leaf, int row, boolean hasFocus) {
    
        String stringValue = tree.convertValueToText(value, isSelected,
        expanded, leaf, row, hasFocus);
        setEnabled(tree.isEnabled());
        check.setSelected(((CheckNode)value).isSelected());
        label.setFont(tree.getFont());
        label.setText(stringValue);
        label.setSelected(isSelected);
        label.setFocus(hasFocus);
        if (leaf) {
            label.setIcon(UIManager.getIcon("Tree.leafIcon"));
        } else if (expanded) {
            label.setIcon(UIManager.getIcon("Tree.openIcon"));
        } else {
            label.setIcon(UIManager.getIcon("Tree.closedIcon"));
        }
        return this;
    }
    
    public Dimension getPreferredSize() {
        Dimension d_check = check.getPreferredSize();
        Dimension d_label = label.getPreferredSize();
        return new Dimension(d_check.width + d_label.width,
            (d_check.height < d_label.height ?
            d_label.height : d_check.height));
    }
    
    public void doLayout() {
        Dimension d_check = check.getPreferredSize();
        Dimension d_label = label.getPreferredSize();
        int y_check = 0;
        int y_label = 0;
        if (d_check.height < d_label.height) {
            y_check = (d_label.height - d_check.height)/2;
        } else {
            y_label = (d_check.height - d_label.height)/2;
        }
        check.setLocation(0,y_check);
        check.setBounds(0,y_check,d_check.width,d_check.height);
        label.setLocation(d_check.width,y_label); 
        label.setBounds(d_check.width,y_label,d_label.width,d_label.height);
    }
    
    public void setBackground(Color color) {
        if (color instanceof ColorUIResource)
            color = null;
        super.setBackground(color);
    }
    
    public class TreeLabel extends JLabel {
        
        boolean isSelected;
        boolean hasFocus;
    
        public TreeLabel() {
        }
    
        public void setBackground(Color color) {
    
            if(color instanceof ColorUIResource)
                color = null;
            super.setBackground(color);
        } 
    
        public void paint(Graphics g) {
            String str;
            if ((str = getText()) != null) {
                if (0 < str.length()) {
                    if (isSelected) {
                        g.setColor(UIManager.getColor("Tree.selectionBackground"));
                    } else {
                        g.setColor(UIManager.getColor("Tree.textBackground"));
                    }
                    Dimension d = getPreferredSize();
                    int imageOffset = 0;
                    Icon currentI = getIcon();
                    if (currentI != null) {
                        imageOffset = currentI.getIconWidth() + Math.max(0, getIconTextGap() - 1);
                    }
                    g.fillRect(imageOffset, 0, d.width -1 - imageOffset, d.height);
                    if (hasFocus) {
                        g.setColor(UIManager.getColor("Tree.selectionBorderColor"));
                        g.drawRect(imageOffset, 0, d.width -1 - imageOffset, d.height -1);
                    }
                }
            }
            super.paint(g);
        }
    
        public Dimension getPreferredSize() {
            Dimension retDimension = super.getPreferredSize();
            if (retDimension != null) {
                retDimension = new Dimension(retDimension.width + 3,
                retDimension.height);
            }
            return retDimension;
        }
    
        public void setSelected(boolean isSelected) {
            this.isSelected = isSelected;
        }
    
        public void setFocus(boolean hasFocus) {
            this.hasFocus = hasFocus;
        }
    }
} 