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;
    }}