ddl.java

有关JDBC的使用一些编程实例,有关与数据库连接的代码

/**
 *
 * DDL.java - Data Definition Language for Chapter 4 Examples
 *
 * 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 java.net.URL;
import java.sql.*;
import java.lang.*;

class DDL {

  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 DDL jdbc:odbc:DATA_SOURCE_NAME;" +
                         "UID=userid;PWD=password");
      System.exit(0);
    }

    String url   = argv[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 = "";
    }

    try {

      // register all of the JDBC classes you might use
      // you can comment out or remove the ones you
      // are not using.
      //
      Class.forName("textFileDriver").newInstance();               // the tinySQL textFile driver
      Class.forName("sun.jdbc.odbc.JdbcOdbcDriver").newInstance(); // JDBC-ODBC bridge
      Class.forName("com.sybase.jdbc.SybDriver").newInstance();    // Sybase
      Class.forName("com.imaginary.sql.msql.MsqlDriver").newInstance();    // mSQL

      Connection con = DriverManager.getConnection(url, user, pwd);
      Statement stmt = con.createStatement();

      // The drops need to be included in these special
      // try...catch clauses. Since the tables might not
      // exist, an exception might be thrown which you
      // want to ignore.
      try {
        stmt.executeUpdate("DROP TABLE tree");
      } catch (Exception e) { }

      // create the tables
      stmt.executeUpdate("CREATE TABLE tree " + 
                         "(name CHAR(80), tree_id INT, parent_id INT)");

      // insert some sample tree items
      // I don't feel like coding each and every
      // insert, so I'm putting it into a two dimensional
      // array, and generating the insert statements from
      // that.
      //
      String data[][] = {
        {"Some sort of lobster-like creature",       "100", "0"},
        {"CEO",                                      "110", "100"},
        {"CFO",                                      "120", "100"},
        {"Regional Managers",                        "130", "110"},
        {"Accounting Manager",                       "140", "120"},
        {"Belligerent, Drunken Mimes",               "150", "240"},
        {"Grunts in the Accounting Department",      "160", "140"},
        {"The crazy guy who brought a gun in " +
	 "and threatened to blow our heads off",         "170", "130"},
        {"A friend of the crazy guy",                "180", "130"},
        {"Sporty Mime",                              "190", "150"},
        {"Scary Mime",                               "200", "150"},
        {"Baby Mime",                                "210", "150"},
        {"Ginger Mime",                              "220", "150"},
        {"Posh Mime",                                "230", "150"},
        {"C3PO",                                     "240", "100"},
        {"R2D2",                                     "250", "240"}
      };
      
      for (int i=0; i < data.length; i++) {
         String insert = "INSERT INTO tree " +
                         " (name, tree_id, parent_id) " + 
                         " VALUES (" +
                         "\'" + data[i][0] + "\', " +
                               data[i][1] + ", " +
                               data[i][2] + ") ";

         stmt.executeUpdate(insert);
      }
      stmt.close();
      con.close();
      System.out.println("Tables were created successfully.");

    } catch (SQLException e) {

      while (e != null) {
        System.out.println("SQLState: " + e.getSQLState());
        System.out.println("Message:  " + e.getMessage());
        System.out.println("Vendor:   " + e.getErrorCode());
        e = e.getNextException();
        System.out.println("");
      }
    } catch (Exception e) {
      e.printStackTrace ();
    }
  }

}