Java Swing How to - Create JTree nodes from enum values

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Question

We would like to know how to create JTree nodes from enum values.

Answer

import java.awt.Component;
/*w  w  w.java2  s  .c  o  m*/
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JScrollPane;
import javax.swing.JTree;
import javax.swing.ToolTipManager;
import javax.swing.tree.DefaultMutableTreeNode;
import javax.swing.tree.DefaultTreeCellRenderer;
import javax.swing.tree.DefaultTreeModel;

public class Main {
  public static void main(String[] args) {
    DefaultMutableTreeNode root = new DefaultMutableTreeNode("Days");
    for (DaysOfTheWeek dotw : DaysOfTheWeek.values()) {
      root.add(new DefaultMutableTreeNode(dotw));
    }
    final DefaultTreeModel model = new DefaultTreeModel(root);
    JTree tree = new JTree(model);
    tree.setRootVisible(true);
    tree.setShowsRootHandles(true);
    ToolTipManager.sharedInstance().registerComponent(tree);
    tree.setCellRenderer(new MyTreeCellRenderer());
    JFrame f = new JFrame();
    f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    f.add(new JScrollPane(tree));
    f.pack();
    f.setVisible(true);
  }

}

enum DaysOfTheWeek {
  MONDAY("Monday", "MON", "First day of the work week."), TUESDAY("Tuesday",
      "TUE", "Second day of the work week");

  private final String fullName;
  private final String abbrvName;
  private final String description;

  private DaysOfTheWeek(String fullName, String abbrvName, String description) {
    this.fullName = fullName;
    this.abbrvName = abbrvName;
    this.description = description;
  }

  public String getFullName() {
    return fullName;
  }

  public String getAbbrvName() {
    return abbrvName;
  }

  public String getDescription() {
    return description;
  }
}

class MyTreeCellRenderer extends DefaultTreeCellRenderer {

  @Override
  public Component getTreeCellRendererComponent(JTree tree, Object value,
      boolean sel, boolean expanded, boolean leaf, int row, boolean hasFocus) {
    Component cell = super.getTreeCellRendererComponent(tree, value, sel,
        expanded, leaf, row, hasFocus);
    if (value instanceof DefaultMutableTreeNode
        && ((DefaultMutableTreeNode) value).getUserObject() instanceof DaysOfTheWeek) {
      ((JLabel) cell).setText(((DaysOfTheWeek) ((DefaultMutableTreeNode) value)
          .getUserObject()).getFullName());
    }
    return cell;
  }
}

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