使用jdbc获取插入数据时的主键的方法

package org.day02;

import java.sql.Connection;
import java.sql.Date;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;

import org.day01.ConnectionUtils;

public class TestPK {
  /**
   * for Oracle
   * 
   * @throws SQLException
   */
  public void addOrder1() throws SQLException {
    Connection con = null;
    PreparedStatement stmt = null;

    try {
      con = ConnectionUtils.getConnection();
      con.setAutoCommit(false);
      // 获取ID
      stmt = con.prepareStatement("select my_order_seq.nextval from dual");
      ResultSet rs = stmt.executeQuery();
      rs.next();
      int orderId = rs.getInt(1);
      System.out.println(orderId);
      stmt.close();

      // 插入Order
      stmt = con.prepareStatement("insert into my_order values(?,?)");
      stmt.setInt(1, orderId);
      stmt.setDate(2, new Date(System.currentTimeMillis()));
      stmt.executeUpdate();
      stmt.close();

      // 插入2个Item
      stmt = con
          .prepareStatement("insert into my_item values(my_item_seq.nextval,?,?)");

      stmt.setString(1, "java");
      stmt.setInt(2, orderId);
      stmt.executeUpdate();

      stmt.setString(1, "php");
      stmt.setInt(2, orderId);
      stmt.executeUpdate();
      stmt.close();

      con.commit();

    } catch (SQLException e) {
      e.printStackTrace();
      con.rollback();
      throw e;
    } finally {
      if (con != null) {
        con.close();
      }
    }
  }

  /**
   * for MySQL
   * 
   * @throws SQLException
   */
  public void addOrder2() throws SQLException {
    Connection con = null;
    PreparedStatement stmt = null;

    try {
      con = ConnectionUtils.getConnection();
      con.setAutoCommit(false);

      // 插入Order
      stmt = con.prepareStatement("insert into my_order values(null,?)",
          Statement.RETURN_GENERATED_KEYS);
      stmt.setDate(1, new Date(System.currentTimeMillis()));
      stmt.executeUpdate();

      ResultSet rs = stmt.getGeneratedKeys();
      rs.next();
      int orderId = rs.getInt(1);
      System.out.println(orderId);
      stmt.close();

      // 插入2个Item
      stmt = con.prepareStatement("insert into my_item values(null,?,?)");

      stmt.setString(1, "java");
      stmt.setInt(2, orderId);
      stmt.executeUpdate();

      stmt.setString(1, "php");
      stmt.setInt(2, orderId);
      stmt.executeUpdate();
      stmt.close();

      con.commit();

    } catch (SQLException e) {
      e.printStackTrace();
      con.rollback();
      throw e;
    } finally {
      if (con != null) {
        con.close();
      }
    }
  }

  public static void main(String[] args) throws Exception {
    TestPK pk = new TestPK();
    pk.addOrder2();
  }
}