Spring之Spring-jdbc-Template使用回调函数用原生JDBC代码执行SQL查询-----Spring框架

package com.powernode.spring6.test;

import com.powernode.spring6.bean.User;
import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;
import org.springframework.dao.DataAccessException;
import org.springframework.jdbc.core.JdbcTemplate;
import org.springframework.jdbc.core.PreparedStatementCallback;

import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;

public class Test
{
    @org.junit.Test
    public void TestCallBack()
    {
        ApplicationContext applicationContext = new ClassPathXmlApplicationContext("spring.xml");
        //如果想写JDBC代码,可以用callback回调函数
        JdbcTemplate jdbcTemplate = applicationContext.getBean("jdbcTemplate", JdbcTemplate.class);
        //准备SQL语句
        String sql = "select id,real_name,age from users where id = ?";
        //注册回调函数,当execute方法执行的时候,回调函数的doInPreparedStatement方法会被执行
        User user = jdbcTemplate.execute(sql, new PreparedStatementCallback<User>() {
            @Override
            public User doInPreparedStatement(PreparedStatement ps) throws SQLException, DataAccessException {
                ps.setInt(1, 3);
                ResultSet resultSet = ps.executeQuery();
                User user = new User();
                while (resultSet.next()) {
                    user.setId(resultSet.getInt("id"));
                    user.setRealName(resultSet.getString("real_name"));
                    ;
                    user.setAge(resultSet.getInt("age"));
                }
                return user;
            }
        });
        System.out.println(user);
    }
}

package com.powernode.spring6.test;

import com.powernode.spring6.bean.User;
import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;
import org.springframework.dao.DataAccessException;
import org.springframework.jdbc.core.JdbcTemplate;
import org.springframework.jdbc.core.PreparedStatementCallback;

import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;

public class Test
{
@org.junit.Test
public void TestCallBack()
{
ApplicationContext applicationContext = new ClassPathXmlApplicationContext("spring.xml");
//如果想写JDBC代码,可以用callback回调函数
JdbcTemplate jdbcTemplate = applicationContext.getBean("jdbcTemplate", JdbcTemplate.class);
//准备SQL语句
String sql = "select id,real_name,age from users where id = ?";
//注册回调函数,当execute方法执行的时候,回调函数的doInPreparedStatement方法会被执行
User user = jdbcTemplate.execute(sql, new PreparedStatementCallback<User>() {
@Override
public User doInPreparedStatement(PreparedStatement ps) throws SQLException, DataAccessException {
ps.setInt(1, 3);
ResultSet resultSet = ps.executeQuery();
User user = new User();
while (resultSet.next()) {
user.setId(resultSet.getInt("id"));
user.setRealName(resultSet.getString("real_name"));
;
user.setAge(resultSet.getInt("age"));
}
return user;
}
});
System.out.println(user);
}
}