三种获得自动生成主键的方法。

package test; 

import java.sql.Connection; 
import java.sql.DriverManager; 
import java.sql.ResultSet; 
import java.sql.Statement; 

/** 
* 三种获得自动生成主键的方法。 
* 
* @author 赵学庆 
* 
*/ 
public class TestGetPK { 

  public static void main(String[] args) throws Exception { 
    Class.forName("com.gbase.jdbc.Driver"); 
    String url = "jdbc:gbase://localhost/mytest"; 
    Connection con = DriverManager.getConnection(url, "root", "111111"); 

    System.out.println(getPK1(con)); 
    System.out.println(getPK2(con)); 
    System.out.println(getPK3(con)); 
  } 

  /** 
   * 使用JDBC 3.0提供的 getGeneratedKeys。推荐使用 
   * 
   * @param con 
   * @return 
   * @throws Exception 
   */ 
  public static long getPK1(Connection con) throws Exception { 
    Statement stmt = con.createStatement(); 
    stmt.executeUpdate("INSERT INTO t_type (name) values ('Can I Get the Auto Increment Field?')", 
        Statement.RETURN_GENERATED_KEYS); 

    int autoIncKeyFromApi = -1; 
    ResultSet rs = stmt.getGeneratedKeys(); 
    if (rs.next()) { 
      autoIncKeyFromApi = rs.getInt(1); 
    } 
    return autoIncKeyFromApi; 
  } 

  /** 
   * 使用数据库自己的特殊SQL. 
   * 
   * @param con 
   * @return 
   * @throws Exception 
   */ 
  public static long getPK2(Connection con) throws Exception { 
    Statement stmt = con.createStatement(); 
    stmt.executeUpdate("INSERT INTO t_type (name) values ('Can I Get the Auto Increment Field?')", 
        Statement.RETURN_GENERATED_KEYS); 

    int autoIncKeyFromFunc = -1; 
    ResultSet rs = stmt.executeQuery("SELECT LAST_INSERT_ID()"); 
    if (rs.next()) { 
      autoIncKeyFromFunc = rs.getInt(1); 
    } 
    return autoIncKeyFromFunc; 
  } 

  /** 
   * 使用可更新的结果集。 
   * 
   * @param con 
   * @return 
   * @throws Exception 
   */ 
  public static long getPK3(Connection con) throws Exception { 
    Statement stmt = con.createStatement(java.sql.ResultSet.TYPE_FORWARD_ONLY, 
        java.sql.ResultSet.CONCUR_UPDATABLE); 
    ResultSet rs = stmt.executeQuery("SELECT * FROM t_Type"); 
    rs.moveToInsertRow(); 
    rs.updateString("name", "AUTO INCREMENT here?"); 
    rs.insertRow(); 
    rs.last(); 
    int autoIncKeyFromRS = rs.getInt("id"); 
    return autoIncKeyFromRS; 
  } 
} 

转载  http://www.java2000.net/p10492