scrollableresultsetexample.java

java 完全探索的随书源码

import java.sql.*;

public class ScrollableResultSetExample
{
  // Private reference to an instance of the Connection
  Connection connection = null;

  // Default Constructor
  public ScrollableResultSetExample( Connection conn )
  {
    super();
    connection = conn;
  }

  // Private accessor for the connection
  private Connection getConnection()
  {
    return connection;
  }

  // Print out the Employee Records backwards using a scrollable
  // ResultSet
  public void printEmployeeRecordsBackwards()
  {
    Statement stmt = null;
    ResultSet rs = null;

    try
    {
      // Get a scrollable ResultSet
      Connection conn = getConnection();
      stmt = conn.createStatement(
                                  ResultSet.TYPE_SCROLL_INSENSITIVE,
                                  ResultSet.CONCUR_READ_ONLY );

      // Get some fields from the employee table
      String sqlQuery = "SELECT EMPNO, EName, Job, MGR, HIREDATE FROM EMP";
      rs = stmt.executeQuery( sqlQuery );
      // Move the cursor directly to the last position in the ResultSet
      // You can't do this like this before JDBC 2.0
      rs.last();

      // Move the cursor backwards through the ResultSet
      while( rs.previous() )
      {
        String nbr = rs.getString( 1 );
        String name = rs.getString( 2 );
        String job = rs.getString( 3 );
        String mgr = rs.getString( 4 );
        Timestamp hireDate = rs.getTimestamp( 5 );

        // Create a new Employee using the data
        Employee emp = new Employee( nbr, name, job, mgr, hireDate );
        // Call the Employee's default toString() method
        System.out.println( emp.toString() );
      }

      rs.close();
    }
    catch( SQLException ex )
    {
      ex.printStackTrace();
    }
  }

  public static void main(String[] args)
  {
     // Use the previous DatabaseManager
    Connection conn = DatabaseManager.getConnection();
    ScrollableResultSetExample example = new ScrollableResultSetExample( conn );
    example.printEmployeeRecordsBackwards();

    // Always make sure to close the connection when you are finished
    try
    {
      conn.close();
    }
    catch( SQLException ex )
    {
      ex.printStackTrace();
    }
    catch( Exception ex )
    {
      ex.printStackTrace();
    }
  }
}