ttree.java

java课程的资料以及实验的代码

import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import javax.swing.event.*;
import javax.swing.tree.*;
import javax.swing.BorderFactory; 
import javax.swing.border.Border;
import javax.swing.border.TitledBorder;
import javax.swing.border.EtchedBorder;
import java.sql.*;

public class TTree extends JPanel {
  JTree tree;
  DefaultTreeModel model;
  DefaultMutableTreeNode selectednode;
  Connection conn;
  int i=0;
  String[] str;

  public TTree() {
    Container cont;
    cont=this;
    cont.setLayout(new BorderLayout());
    Border b = BorderFactory.createEtchedBorder(EtchedBorder.LOWERED);
    
    conn = (new DbConn()).getConnection();
    if (conn == null) {
      	System.out.println("Can not connected yet!");
    }
	try {
		Statement stmt = conn.createStatement();
		ResultSet rset = stmt.executeQuery ("select asset_name from asset");
		str=new String[50];
		while (rset.next()) {
			str[i] = rset.getString(1);
			i++;
		}
		conn.commit(); 
      	rset.close();
      	stmt.close();
      	conn.close();
	}
	catch (java.sql.SQLException s) {
		System.out.println("exception: " + s.getMessage());
	}
    
//建立一颗树
    DefaultMutableTreeNode root = new DefaultMutableTreeNode("资产管理");
    for(int j=0;j<i;j++)
    {
    	DefaultMutableTreeNode node = new DefaultMutableTreeNode(str[j]);
    	root.add(node);
    }
//    DefaultMutableTreeNode isep = new DefaultMutableTreeNode("ISEP");
//    root.add(isep);
   
    //使用头节点创建树
    tree = new JTree(root);
    model=(DefaultTreeModel)tree.getModel();
    JScrollPane jsp = new JScrollPane(tree);
    cont.add(jsp, BorderLayout.CENTER); 
    	
    setBorder(b);
    setVisible(true);
 }
}