outlinejtree.java

有关JDBC的使用一些编程实例,有关与数据库连接的代码

/*
 *
 * outlineJTree.java
 *
 * an extension of outline.class using the JFC (Swing) JTree component.
 *
 * Copyright 1996 John Wiley & Sons, Inc. All Rights Reserved. Reproduction
 * or translation of this work beyond that permitted in Section 117 of the 1976
 * United States Copyright Act without the express written permission of the
 * copyright owner is unlawful. Requests for further information should be 
 * addressed to Permissions Department, John Wiley & Sons, Inc. The 
 * purchaser may make back-up copies for his/her own use only and not for 
 * distribution or resale. The Publisher assumes no responsibility for errors, 
 * omissions, or damages, caused by the use of this  software or from the use
 * of the information contained herein.
 *
 */

import com.sun.java.swing.*;
import com.sun.java.swing.text.*;
import com.sun.java.swing.tree.*;

import java.awt.event.*;
import java.util.*;
import java.awt.*;
import java.sql.*;

class outlineJTree extends outline {

  JTree tree;
  DefaultMutableTreeNode top = new DefaultMutableTreeNode("");;
  Stack node_stack = new Stack();
  int curr_level = 1;

  /**
   *
   * Constructs a new outlineJTree object.
   * @param url a URL to  a valid JDBC data source.
   * @param user a username
   * @param pwd a password
   * @param t an MlTree object
   *
   */
  public outlineJTree (String url, String user, String pwd) {

    super(url, user, pwd);
    node_stack.push(top);

  }

  DefaultMutableTreeNode getTop() {
      return top;
  }


  /**
   *
   * addNode()
   *
   * This subclasses the addNode() method in outline.class to
   * use an MlTree
   *
   * @param level the level within the tree (starts at 1)
   * @param children the number of children
   * @param label the text of the item
   *
   */
  void addNode (int level, int children, String label) {

    // Pop the stack until we are sitting on this node's parent.
    //
    for (int i = curr_level; i > level; i--) {
            node_stack.pop();
    }

    // Create the new node.
    //
    DefaultMutableTreeNode new_node = new DefaultMutableTreeNode(label);

    // Get the parent of this node from the stack.
    //
    DefaultMutableTreeNode current = 
        (DefaultMutableTreeNode) node_stack.peek();

    // Add the new node to the parent node.
    //
    current.add(new_node);


    // If this node has children, add it to the stack of nodes.
    //
    if (children != 0) {
        node_stack.push(new_node);
    }

    // Save the current level of this node.
    //
    curr_level = level;

  }

  /**
   * 
   * instantiate the outline object with test data.
   *
   */
  public static void main (String argv[]) {

    if (argv.length == 0) {
    	System.out.println("You must supply a URL to a JDBC data source.");
    	System.out.println("");
    	System.out.println("Example:");
    	System.out.println("java outlineJTree jdbc:odbc:DATA_SOURCE_NAME;" +
	                   "UID=userid;PWD=password");
      System.exit(0);
    }

    // the user might have passed in a user name or password,
    // so try to read those in, as well
    //
    String user, pwd;
    if (argv.length > 1) {
      user = argv[1];
    } else {
      user = "";
    }
    if (argv.length > 2) {
      pwd = argv[2];
    } else {
      pwd = "";
    }

    // create a Frame.
    //
    Frame f = new Frame();

    // Set up a WindowAdapter that can close the Frame when the user clicks
    // on the close control.
    //
    f.addWindowListener(new WindowAdapter() {
        public void windowClosing(WindowEvent e) {
            System.exit(0);
        }
    });

    // Set the Frame's layout.
    //
    f.setLayout(new BorderLayout());

    // instantiate the outlineJTree object and traverse it
    //
    outlineJTree tr = new outlineJTree(argv[0], user, pwd);
    tr.traverseTree("tree", "tree_id", "parent_id", "name");

    JTree tree = new JTree(tr.getTop());
    f.add("Center", tree);
    f.setSize(400, 300);
    f.show();    

  }

}