jdbc_commit.java

来自「有关JDBC的使用一些编程实例,有关与数据库连接的代码」· Java 代码 · 共 98 行

/*
 * 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.*;

class jdbc_commit {

  public static void main(String argv[]) {

    try {
      Class.forName("sun.jdbc.odbc.JdbcOdbcDriver").newInstance(); // JDBC-ODBC bridge
      Class.forName("com.sybase.jdbc.SybDriver").newInstance();    // Sybase
    } catch (Exception e) {
      e.printStackTrace();
    }

    try {

      // the url, userid, and password come in from argv, so error out if
      // they weren't passed.
      //
      if (argv.length < 3) {
         System.err.println("Usage:");
         System.err.println("");
         System.err.println("java jdbc_commit URL userid password");
         System.err.println("");
         System.err.println("  Examples:");
         System.err.println(
           "  java jdbc_commit jdbc:odbc:MSSQL javadb javadb");
         System.err.println(
           "  java jdbc_commit jdbc:sybase:Tds:localhost:4000 javadb javadb");
         System.exit(0);
      }

      String url  = argv[0];
      String user = argv[1];
      String pwd  = argv[2];

      // make a connection to the specified URL
      //
      Connection con = DriverManager.getConnection(url, user, pwd);

      // set auto-commit mode off; it is on by default. 
      //
      con.setAutoCommit(false);

      // get a statement object
      //
      Statement stmt = con.createStatement();

      String sql = "UPDATE food SET price = $78.98 " +
                   "WHERE  product = 'Cheeseburger'";
      stmt.executeUpdate(sql);

      // issue the commit
      //
      con.commit();

      // get a new connection, since the last one was closed
      // (not all drivers are capable of disabling autoclose)
      //
      con = DriverManager.getConnection(url, user, pwd);

      // get a new statement, since the last one was closed
      //
      stmt = con.createStatement();

      // execute a query to check the value of price
      //
      ResultSet rs = stmt.executeQuery("SELECT price FROM food " +
	                               "WHERE product = 'Cheeseburger'");

      rs.next();
      System.out.println( rs.getString(1) );
   
      stmt.close();
      con.close();

    }
    catch( Exception e ) {
      System.out.println(e.getMessage());
      e.printStackTrace();
    }
  }

}