Spring对Jdbc的封装——JdbcTemplate的使用

链接：https://pan.baidu.com/s/15luDElW4oeEaP0nvEQ_40w

提取码：i2r1

JdbcTemplate是Spring对JDBC的封装，目的是使JDBC更加易于使用。JdbcTemplate是Spring的一部分。

接下来，使用JdbcTemplate进行增删改查（CRUD）的操作

写一个pojo类（不是重点）

 package top.bigking.pojo;

 import java.util.Date;

 public class User {
     private Integer id;
     private String username;
     private String password;
     private Date birthday;
     private Integer age;

     public User() {
     }

     public User(Integer id, String username, String password, Date birthday, Integer age) {
         this.id = id;
         this.username = username;
         this.password = password;
         this.birthday = birthday;
         this.age = age;
     }

     public User(String username, String password, Date birthday, Integer age) {
         this.username = username;
         this.password = password;
         this.birthday = birthday;
         this.age = age;
     }

     public Integer getId() {
         return id;
     }

     public void setId(Integer id) {
         this.id = id;
     }

     public String getUsername() {
         return username;
     }

     public void setUsername(String username) {
         this.username = username;
     }

     public String getPassword() {
         return password;
     }

     public void setPassword(String password) {
         this.password = password;
     }

     public Date getBirthday() {
         return birthday;
     }

     public void setBirthday(Date birthday) {
         this.birthday = birthday;
     }

     public Integer getAge() {
         return age;
     }

     public void setAge(Integer age) {
         this.age = age;
     }

     @Override
     public String toString() {
         return "User{" +
                 "id=" + id +
                 ", username='" + username + '\'' +
                 ", password='" + password + '\'' +
                 ", birthday=" + birthday +
                 ", age=" + age +
                 '}';
     }
 }

再写一个接口

 package top.bigking.dao;

 import top.bigking.pojo.User;

 import java.util.List;

 public interface UserDao {
     public int insertUser(User user);
     public int deleteById(Integer id);
     public int updateUser(User user);
     public List<User> queryUser();
     public User selectUserById(Integer id);
 }

接下来对接口进行实现：

 package top.bigking.dao.impl;

 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.jdbc.core.BeanPropertyRowMapper;
 import org.springframework.jdbc.core.JdbcTemplate;
 import org.springframework.stereotype.Repository;
 import top.bigking.dao.UserDao;
 import top.bigking.pojo.User;

 import java.util.List;

 @Repository("userDao")
 public class UserDaoImpl implements UserDao {
     @Autowired
     private JdbcTemplate jdbcTemplate;

     @Override
     public int insertUser(User user) {
         String sql = "insert into t_user(user_name, password, birthday, age) values(?, ?, ?, ?)";
         return jdbcTemplate.update(sql, user.getUsername(), user.getPassword(), user.getBirthday(), user.getAge());
     }

     @Override
     public int deleteById(Integer id) {
         String sql = "delete from t_user where id = ?";
         return jdbcTemplate.update(sql, id);
     }

     @Override
     public int updateUser(User user) {
         String sql = "update t_user set user_name = ?, password = ?, birthday = ?, age = ?";
         return jdbcTemplate.update(sql, user.getUsername(), user.getPassword(), user.getBirthday(), user.getAge());
     }

     @Override
     public List<User> queryUser() {
         String sql = "select * from t_user";
         return jdbcTemplate.query(sql, new BeanPropertyRowMapper<>(User.class));
     }

     @Override
     public User selectUserById(Integer id) {
         String sql = "select * from t_user where id = ?";
         return jdbcTemplate.queryForObject(sql, new BeanPropertyRowMapper<>(User.class), id);
     }
 }

接下来使用单元测试一个一个测试：

 package top.bigking.test;

 import org.junit.Before;
 import org.junit.Test;
 import org.springframework.context.ApplicationContext;
 import org.springframework.context.support.ClassPathXmlApplicationContext;
 import top.bigking.dao.UserDao;
 import top.bigking.pojo.User;

 import java.util.Date;
 import java.util.List;

 public class TestJdbc {
     private UserDao userDao;

     @Before
     public void connect(){
         ApplicationContext applicationContext = new ClassPathXmlApplicationContext("application.xml");
         userDao = (UserDao) applicationContext.getBean("userDao");
     }
     @Test
     public void testConnect(){
         User user = userDao.selectUserById(6);
         System.out.println(user);
     }
     @Test
     public void testInsertUser(){
         User user = new User("ABKing", "123456", new Date(), 20);
         System.out.println(userDao.insertUser(user));
     }

     @Test
     public void testDeleteUser(){
         System.out.println(userDao.deleteById(6));
     }
     @Test
     public void testUpdateUser(){
         User user = new User(36, "ABKing", "666666", new Date(), 20);
         System.out.println(userDao.updateUser(user));
     }
     @Test
     public void testQuery(){
         List<User> userList = userDao.queryUser();
         for(User user : userList){
             System.out.println(user);
         }
     }
 }