batchupdateexample.java

来自「java 完全探索的随书源码」· Java 代码 · 共 87 行

import java.sql.*;

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

  // Default Constructor
  public BatchUpdateExample( 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 batchUpdates()
  {
    Statement stmt = null;
    ResultSet rs = null;

    try
    {
      // Start a transaction
      getConnection().setAutoCommit( false );

      stmt = getConnection().createStatement();
      stmt.addBatch( "UPDATE EMP SET JOB = 1" );
      stmt.addBatch( "UPDATE EMP SET HIREDATE = '17-DEC-1999'" );

      // Submit the batch of commands for this statement to the database
      stmt.executeBatch();

      // Commit the transaction
      getConnection().commit();

      // Close the existing to be safe before opening a new one
      stmt.close();

      // Print out the Employees
      stmt = getConnection().createStatement();
      rs = stmt.executeQuery( "SELECT * FROM EMP" );
      // Loop through and print the employee number, job, and hiredate
      while( rs.next() )
      {
        int id = rs.getInt( "EMPNO" );
        int job = rs.getInt( "JOB" );
        String hireDate = rs.getString( "HIREDATE" );

        System.out.println( id + ":" + job + ":" + hireDate );
      }

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

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

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