Java DefaultCellEditor .getTreeCellEditorComponent (JTree tree, Object value, boolean isSelected, boolean expanded, boolean leaf, int row)

public Component getTreeCellEditorComponent(JTree tree,     Object value,     boolean isSelected,     boolean expanded,     boolean leaf,     int row)

import java.awt.Component;
/*from   w  w  w.j  ava  2 s.  c o  m*/
import javax.swing.DefaultCellEditor;
import javax.swing.JCheckBox;
import javax.swing.JFrame;
import javax.swing.JScrollPane;
import javax.swing.JTree;
import javax.swing.tree.DefaultMutableTreeNode;
import javax.swing.tree.DefaultTreeCellRenderer;
import javax.swing.tree.MutableTreeNode;
import javax.swing.tree.TreePath;

class MyData {

  protected final String value;
  protected boolean booleanValue;

  public MyData(String quest) {
    value = quest;
  }

  public String getQuestion() {
    return value;
  }

  public boolean getAnswer() {
    return booleanValue;
  }

  public void setAnswer(boolean ans) {
    booleanValue = ans;
  }

  public String toString() {
    return value + " = " + booleanValue;
  }
}

public class Main extends JFrame {

  protected final static String[] questions = { "A","B","C" };

  public static void main(String[] args) {
    Main tt = new Main();
    tt.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    tt.setSize(500, 200);
    tt.setVisible(true);
  }

  public Main() {
    super();
    JTree tree = new JTree(getRootNode()) {
      public boolean isPathEditable(TreePath path) {
        Object comp = path.getLastPathComponent();
        if (comp instanceof DefaultMutableTreeNode) {
          DefaultMutableTreeNode node = (DefaultMutableTreeNode) comp;
          Object userObject = node.getUserObject();
          if (userObject instanceof Main) {
            return true;
          }
        }
        return false;
      }
    };
    QuestionCellRenderer renderer = new QuestionCellRenderer();
    tree.setCellRenderer(renderer);
    QuestionCellEditor editor = new QuestionCellEditor();
    tree.setCellEditor(editor);
    tree.setEditable(true);
    JScrollPane jsp = new JScrollPane(tree);
    getContentPane().add(jsp);
  }

  protected MutableTreeNode getRootNode() {
    DefaultMutableTreeNode root, child;
    MyData question;
    root = new DefaultMutableTreeNode("Root");
    for (int i = 0; i < questions.length; i++) {
      question = new MyData(questions[i]);
      child = new DefaultMutableTreeNode(question);
      root.add(child);
    }
    return root;
  }

}

class QuestionCellRenderer extends DefaultTreeCellRenderer {

  protected JCheckBox checkBoxRenderer = new JCheckBox();

  public Component getTreeCellRendererComponent(JTree tree, Object value,
      boolean selected, boolean expanded, boolean leaf, int row,
      boolean hasFocus) {
    if (value instanceof DefaultMutableTreeNode) {
      DefaultMutableTreeNode node = (DefaultMutableTreeNode) value;
      Object userObject = node.getUserObject();
      if (userObject instanceof Main) {
        MyData question = (MyData) userObject;
        prepareQuestionRenderer(question, selected);
        return checkBoxRenderer;
      }
    }
    return super.getTreeCellRendererComponent(tree, value, selected, expanded,
        leaf, row, hasFocus);
  }

  protected void prepareQuestionRenderer(MyData tfq, boolean selected) {
    checkBoxRenderer.setText(tfq.getQuestion());
    checkBoxRenderer.setSelected(tfq.getAnswer());
    if (selected) {
      checkBoxRenderer.setForeground(getTextSelectionColor());
      checkBoxRenderer.setBackground(getBackgroundSelectionColor());
    } else {
      checkBoxRenderer.setForeground(getTextNonSelectionColor());
      checkBoxRenderer.setBackground(getBackgroundNonSelectionColor());
    }
  }

}

class QuestionCellEditor extends DefaultCellEditor {

  protected MyData nodeData;

  public QuestionCellEditor() {
    super(new JCheckBox());
  }

  public Component getTreeCellEditorComponent(JTree tree, Object value,
      boolean selected, boolean expanded, boolean leaf, int row) {
    JCheckBox editor = null;
    nodeData = getQuestionFromValue(value);
    if (nodeData != null) {
      editor = (JCheckBox) (super.getComponent());
      editor.setText(nodeData.getQuestion());
      editor.setSelected(nodeData.getAnswer());
    }
    return editor;
  }

  public static MyData getQuestionFromValue(Object value) {
    if (value instanceof DefaultMutableTreeNode) {
      DefaultMutableTreeNode node = (DefaultMutableTreeNode) value;
      Object userObject = node.getUserObject();
      if (userObject instanceof Main) {
        return (MyData) userObject;
      }
    }
    return null;
  }

  public Object getCellEditorValue() {
    JCheckBox editor = (JCheckBox) (super.getComponent());
    nodeData.setAnswer(editor.isSelected());
    return nodeData;
  }

}