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

曾经终败给现在 2024-03-24 00:00 60阅读 0赞

>     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);  
> \}  
> \}