Spring中新建记录后返回自增主键的处理方法

接手一个旧系统改造的过程，要插入后立即返回自增值，不能重构guid类型主键，Spring提供了很优美的机制。

Spring利用GeneratedKeyHolder，提供了一个可以返回新增记录对应主键值的方法 :KeyHolder接口指代了一个通用的实现类GeneratedKeyHolder，该类返回新增记录时的自增长主键值

代码：

import java.sql.Connection;

import java.sql.PreparedStatement;

import java.sql.SQLException;

import java.util.Date;

import org.springframework.context.ApplicationContext;

import org.springframework.context.support.ClassPathXmlApplicationContext;

import org.springframework.jdbc.core.JdbcTemplate;

import org.springframework.jdbc.core.PreparedStatementCreator;

import org.springframework.jdbc.support.GeneratedKeyHolder;

import org.springframework.jdbc.support.KeyHolder;

import javax.sql.DataSource;

public class Main {

    public static void main(String[] args) {

        ApplicationContext context = new ClassPathXmlApplicationContext("TemporaryVenue-test.xml");

        DataSource dataSource = (DataSource)context.getBean("dataSource");

        JdbcTemplate  jdbcTemplate = new JdbcTemplate(dataSource);     

        String insert_sql = "insert into SYS_USERTV(username,password) values(?,?)";         

        //调用，获取插入后的自增值，其中"id"是自增字段名称

        System.out.println("方法调用获取当前自增int主键值" + insert(insert_sql,jdbcTemplate,"id"));

    }

    /**

     * 插入后返回自增主键值

     * @param jdbcTemplate

     * @return

     */

    private static Number insert(final String sql,

            JdbcTemplate jdbcTemplate,

            final String keyName) {

       KeyHolder keyHolder = new GeneratedKeyHolder();

        int lines=jdbcTemplate.update(new PreparedStatementCreator() {

            @Override

            public PreparedStatement createPreparedStatement(Connection connection)

                    throws SQLException {

                PreparedStatement ps = PreStatement(sql, connection,keyName);

                return ps;

            }

        }, keyHolder);

            return keyHolder.getKey();

    }

    /**

     * 装载参数

     * @param sql

     * @param connection

     * @param keyName：自增字段名称

     * @return

     * @throws SQLException

     */

    private static PreparedStatement PreStatement(final String sql,

            Connection connection,String keyName) throws SQLException {

        PreparedStatement ps = connection.prepareStatement(sql,

                new String[] { keyName });

        ps.setString(1, new Date().toString());

        ps.setString(2, "aa");

        return ps;

    }

}