emptree.java

JAVA编程百例书中各章节的所有例子的源代码,包括套接字编程

package ch10.section08;

import java.util.*;

import java.awt.*;
import javax.swing.*;
import javax.swing.border.*;
import javax.swing.event.*;
import javax.swing.tree.*;

public class empTree
    extends JxFrame
    implements TreeSelectionListener {
  Employee boss, marketVP, prodVP;
  Employee salesMgr, advMgr;
  Employee prodMgr, shipMgr;

  JScrollPane sp;
  JPanel treePanel;
  JTree tree;
  DefaultMutableTreeNode troot;
  JLabel cost;

  public empTree() {
    super("Employee tree");
    makeEmployees();
    setGUI();
  }

  private void setGUI() {
    treePanel = new JPanel();
    getContentPane().add(treePanel);
    treePanel.setLayout(new BorderLayout());

    sp = new JScrollPane();
    treePanel.add("Center", sp);
    treePanel.add("South", cost = new JLabel("          "));

    treePanel.setBorder(new BevelBorder(BevelBorder.RAISED));
    troot = new DefaultMutableTreeNode(boss.getName());
    tree = new JTree(troot);
    tree.setBackground(Color.lightGray);
    loadTree(boss);

    sp.getViewport().add(tree);
    setSize(new Dimension(200, 300));
    setVisible(true);

  }

  public void loadTree(Employee topDog) {
    DefaultMutableTreeNode troot;
    troot = new DefaultMutableTreeNode(topDog.getName());
    treePanel.remove(tree);
    tree = new JTree(troot);
    tree.addTreeSelectionListener(this);
    sp.getViewport().add(tree);

    addNodes(troot, topDog);
    tree.expandRow(0);
    repaint();
  }

  private void addNodes(DefaultMutableTreeNode pnode, Employee emp) {
    DefaultMutableTreeNode node;

    Enumeration e = emp.elements();
    while (e.hasMoreElements()) {
      Employee newEmp = (Employee) e.nextElement();
      node = new DefaultMutableTreeNode(newEmp.getName());
      pnode.add(node);
      addNodes(node, newEmp);
    }
  }

  private void makeEmployees() {
    boss = new Employee("CEO", 200000);
    boss.add(marketVP = new Employee("Marketing VP", 100000));
    boss.add(prodVP = new Employee("Production VP", 100000));

    marketVP.add(salesMgr = new Employee("Sales Mgr", 50000));
    marketVP.add(advMgr = new Employee("Advt Mgr", 50000));

    for (int i = 0; i < 5; i++) {
      salesMgr.add(new Employee("Sales " + new Integer(i).toString(),
                                30000.0F +
                                (float) (Math.random() - 0.5) * 10000));
    }
    advMgr.add(new Employee("Secy", 20000));

    prodVP.add(prodMgr = new Employee("Prod Mgr", 40000));
    prodVP.add(shipMgr = new Employee("Ship Mgr", 35000));
    for (int i = 0; i < 4; i++) {
      prodMgr.add(new Employee("Manuf " + new Integer(i).toString(),
                               25000.0F + (float) (Math.random() - 0.5) * 5000));
    }
    for (int i = 0; i < 3; i++) {
      shipMgr.add(new Employee("ShipClrk " + new Integer(i).toString(),
                               20000.0F + (float) (Math.random() - 0.5) * 5000));

    }
  }

  public void valueChanged(TreeSelectionEvent evt) {
    TreePath path = evt.getPath();
    String selectedTerm = path.getLastPathComponent().toString();

    Employee emp = boss.getChild(selectedTerm);
    if (emp != null) {
      cost.setText(new Float(emp.getSalaries()).toString());
    }
  }

  static public void main(String argv[]) {
    new empTree();
  }
}