Bank account transfer

[sajohnson05]

Here is my code for a JDBC program to do account transfer. I am having trouble with my transfer code. Can anyone help. This is urgent.

import java.sql.*; 

/*****************************************************

class BankAccountTransfer { 
  

  /** Make a transfer from two accounts owned by same customer.
   * @param custNum the 6-digit customer number
   * @param custPasswd the customer's password
   * @param acctNumFrom the 8-digit acct# to transfer from; owned by custNum
   * @param acctNumTo   the 8-digit acct# to transfer to;   owned by custNum
   * @param amt The amount to transfer.
   * @return a string with a user-friendly result.  
   *   The string starts with "ERROR" iff the transfer didn't go through.
   */
  public static String makeTransfer( String custNum, String custPasswd,
                     String acctNumFrom, String acctNumTo, double amt ) {
    String msgStart = "Transfer from " + acctNumFrom + " to " + acctNumTo + " ";
    String errMsgStart = "ERROR -- " + msgStart + " cancelled:\n  ";
    try {
      String q1 = "select password from bankcustomers where custid = '" + custNum + "'";
      ResultSet passwdResults = conn.createStatement().executeQuery(q1);
      
      boolean gotSomeResults = passwdResults.next();
      if (!gotSomeResults) {
        return errMsgStart + "No such customer number " + custNum;
        }
      // If we make it here, 'passwdResults' is pointing at the first (only) customer record.
      if (! custPasswd.equals( passwdResults.getString("password") )) {
        return errMsgStart + "Incorrect password";
        }
         
      // If we make it here, we have verified that the password and custNum passed in
      // to this method really do match what is off in the database.
      conn.setAutoCommit(false);
	// TODO:  Complete the transfer.
      // Print an error message and return if:
      //  - either the 'from' or 'to' account doesn't exist w/ expected owner

  
      //  - insufficient funds
          if (amt < 0) {
              return errMsgStart + "insufficient funds"
                         + (amt);
          }
      
      // Otherwise use 'conn.createStatement().executeUpdate(...)'
      // to change the balances in the two accounts.

      return msgStart + "succeeded.";
  	conn.commit();

	conn.setAutoCommit(true);
      }
    
    catch (SQLException e) {
      return  errMsgStart + "DB error " + e.toString();
    }
    
    }
      
/** Make several transfers, to test.
   * (This method opens *and* closes one db connection.)
   */  
  public static void main (String args []) throws SQLException { 
    try {
      DriverManager.registerDriver (new oracle.jdbc.driver.OracleDriver());
      conn = DriverManager.getConnection( DB_CONNECT_INFO, DB_USER, DB_USER_PASSWD );
      
      System.out.println( makeTransfer( "111111", "highlander", 
                                        "00000001", "00000002", 10.00 ) );  // succeed
      System.out.println( makeTransfer( "111119", "highlander", 
	                                "00000001", "00000002", 12.34 ) );  // fail - no such user
      System.out.println( makeTransfer( "111111", "lowlander",  
                                        "00000001", "00000002", 12.34 ) );  // fail-wrong passwd
      System.out.println( makeTransfer( "111111", "highlander",
                                        "00000001", "00000002", 12345.67 ) );  // fail-insuf funds
      System.out.println( makeTransfer( "111111", "highlander", 
                                        "00000001", "00000003", 12.34 ) );  // fail-don't own acct
      System.out.println( makeTransfer( "111111", "highlander", 
                                        "00000003", "00000002", 12.34 ) );  // fail-don't own acct
      System.out.println( makeTransfer( "222222", "ruready", 
              							"00000003", "00000003", 250.66 ) );  // succeed
      System.out.println( makeTransfer( "222222", "ruready", 
    		  							"00000003", "00000004", 3500.23 ) );  // succeed
      System.out.println( makeTransfer( "222222", "ruready", 
    		  							"00000003", "00000003", 550.23 ) );  // succeed
      System.out.println( makeTransfer( "222222", "ruready", 
										"00000003", "00000003", 17550.23 ) );  // fail-insuf funds
      System.out.println( makeTransfer( "222222", "dreadred", 
										"00000003", "00000004", 550.23 ) );  // fail-wrong passwd
      System.out.println( makeTransfer( "222223", "ruready", 
										"00000003", "00000004", 550.23 ) );  // fail - no such user
                                        
      // see the bankAccountSchema.sql for her password etc.
      }
    catch (SQLException e){ 
      System.err.println ("Could not load the db "+e);
      }
    finally {
      if (conn != null) conn.close();  // N.B. This alone could raise an exception.
      }
    } 

  // Class fields:  
  private static Connection conn;  // init'd at start of main(), closed at the end.  
  private static final String DB_CONNECT_INFO = "jdbc:oracle:thin:@Picard.radford.edu:1521:teaching";
  private static final String DB_USER = "sajohnson";  // do NOT include the "@ITEC"
  private static final String DB_USER_PASSWD = "Welcome";
  }

[jwenting]

not urgent