手撕Spring5框架（八）操作JdbcTemplate
什么是JdbcTemplate？
Spring 框架对JDBC进行封装，使用JDBCTemplate方便实现对数据库的才做。
如何使用jdbcTemplate？
准备工作
- 引用jar包
org.springframework
spring-jdbc
5.2.8.RELEASE
org.springframework
spring-orm
5.2.8.RELEASE
org.springframework
spring-tx
5.2.8.RELEASE
mysql
mysql-connector-java
8.0.13
com.alibaba
druid
1.1.14
- 配置数据库连接池
- 配置jdbcTemplate对象，注入DataSource
- 创建jdbc.properties
prop.driverClass=com.mysql.cj.jdbc.Driver
prop.url=jdbc:mysql://127.0.0.1:3306/spring5-demo?characterEncoding=utf8&useSSL=false&serverTimezone=GMT%2B8&zeroDateTimeBehavior=CONVERT_TO_NULL
prop.userName=root
prop.password=123456- 创建service类，dao类，在dao类注入jdbcTemplate对象
package org.learn.spring5.service.impl;
import org.learn.spring5.dao.impl.UserDaoImpl;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
@Service
public class UserServiceImpl implements UserService {
//注入UserDao的对象
@Autowired
private UserDaoImpl userDao;
}
package org.learn.spring5.dao.impl;
import org.learn.spring5.service.impl.UserServiceImpl;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.jdbc.core.JdbcTemplate;
public class UserDaoImpl implements UserDao{
//注入JdbcTemplate對象
@Autowired
private JdbcTemplate jdbcTemplate;
}
- 编写实体类User
package org.learn.spring5.entiy;
public class User {
//id
private Integer id;
//用户名
private String userName;
//用户状态
private Integer status;
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 Integer getStatus() {
return status;
}
public void setStatus(Integer status) {
this.status = status;
}
}
- 创建数据和表结构
DROP TABLE IF EXISTS `t_user`;
CREATE TABLE `t_user` (
`id` int(11) NOT NULL,
`user_name` varchar(22) CHARACTER SET utf8 COLLATE utf8_general_ci NULL DEFAULT NULL,
`status` int(11) NULL DEFAULT NULL,
PRIMARY KEY (`id`) USING BTREE
) ENGINE = InnoDB CHARACTER SET = utf8 COLLATE = utf8_general_ci ROW_FORMAT = Dynamic;
SET FOREIGN_KEY_CHECKS = 1;具体操作
- JdbcTemplate操作数据库-添加功能
1）在UserDaoImpl类里添加add方法
2）调用JdbcTemplate对象的update方法
package org.learn.spring5.dao.impl;
import org.learn.spring5.entiy.User;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.jdbc.core.JdbcTemplate;
import org.springframework.stereotype.Component;
@Component
public class UserDaoImpl implements UserDao{
//注入JdbcTemplate對象
@Autowired
private JdbcTemplate jdbcTemplate;
public void add(User user) {
//1.創建sql語句
String sql="insert into t_user values(?,?,?)";
//2.調用方法实现
Object[] args={user.getId(),user.getUserName(),user.getStatus()};
int update = jdbcTemplate.update(sql, args);
System.out.println(update);
}
}
3)编写测试程序
import org.junit.Test;
import org.learn.spring5.entiy.User;
import org.learn.spring5.service.impl.UserService;
import org.learn.spring5.service.impl.UserServiceImpl;
import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;
public class TestSpring5 {
/**
* 操作JdbcTemplate，添加操作
*/
@Test
public void testAdd() {
ApplicationContext context = new ClassPathXmlApplicationContext("bean1.xml");
UserService userService = context.getBean("userServiceImpl", UserServiceImpl.class);
User user = new User();
user.setId(1);
user.setUserName("张三");
user.setStatus(1);
userService.addUser(user);
}
}
程序返回结果1，标识数据添加成功！
- JdbcTemplate操作数据库-修改功能
public int update(User user) {
String sql = "update t_user set user_name =?,status=? where id =?";
Object[] args = {user.getUserName(), user.getStatus(), user.getId()};
int update = jdbcTemplate.update(sql, args);
return update;
}编写测试程序
//JdbcTemplate修改操作
@Test
public void testUpdate() {
ApplicationContext context = new ClassPathXmlApplicationContext("bean1.xml");
UserService userService = context.getBean("userServiceImpl", UserServiceImpl.class);
User user = new User();
user.setId(1);
user.setUserName("张四");
user.setStatus(0);
userService.update(user);
}- JdbcTemplate操作数据库-查询功能
1）查询返回某一个值
public int queryCount() {
String sql = "select count(*) from t_user";
Integer count = jdbcTemplate.queryForObject(sql, Integer.class);
return count;
}编写测试程序
//JdbcTemplate 查询操作，返回用户的数量
@Test
public void testQueryCount() {
ApplicationContext context = new ClassPathXmlApplicationContext("bean1.xml");
UserService userService = context.getBean("userServiceImpl", UserServiceImpl.class);
int count = userService.queryCount();
System.out.println(count);
}2）查询返回对象
public User findOne(Integer id) {
String sql = "select * from t_user where id =?";
User user = jdbcTemplate.queryForObject(sql, new BeanPropertyRowMapper(User.class), id);
return user;
} 编写测试程序
//JdbcTemplate 查询操作，返回对象根据id
@Test
public void testQueryById() {
ApplicationContext context = new ClassPathXmlApplicationContext("bean1.xml");
UserService userService = context.getBean("userServiceImpl", UserServiceImpl.class);
User user = userService.queryById(1);
System.out.println(user);
}3）查询返回集合
//JdbcTemplate 查询操作，返回集合对象
@Test
public void testFindAll() {
ApplicationContext context = new ClassPathXmlApplicationContext("bean1.xml");
UserService userService = context.getBean("userServiceImpl", UserServiceImpl.class);
List all = userService.findAll();
System.out.println(all);
} 编写测试程序
//JdbcTemplate 查询操作，返回集合对象
@Test
public void testFindAll() {
ApplicationContext context = new ClassPathXmlApplicationContext("bean1.xml");
UserService userService = context.getBean("userServiceImpl", UserServiceImpl.class);
List all = userService.findAll();
System.out.println(all);
} - JdbcTemplate操作数据库-删除功能
public int del(Integer id) {
String sql = "delete from t_user where id =?";
int update = jdbcTemplate.update(sql, id);
return update;
}编写测试程序
//JdbcTemplate删除操作
@Test
public void testDel() {
ApplicationContext context = new ClassPathXmlApplicationContext("bean1.xml");
UserService userService = context.getBean("userServiceImpl", UserServiceImpl.class);
userService.del(1);
}- JdbcTemplate操作数据库-批量添加
public void batchAdd(List users) {
String sql = "insert into t_user values(?,?,?)";
int[] ints = jdbcTemplate.batchUpdate(sql, users);
System.out.println(Arrays.asList(ints));
} 编写测试程序
//JdbcTemplate 批量添加操作
@Test
public void batchAdd() {
ApplicationContext context = new ClassPathXmlApplicationContext("bean1.xml");
UserService userService = context.getBean("userServiceImpl", UserServiceImpl.class);
List list = new ArrayList();
Object[] o1 = {"4","name1",0};
Object[] o2 = {"5","name2",0};
Object[] o3 = {"6","name3",0};
list.add(o1);
list.add(o2);
list.add(o3);
userService.batchAdd(list);
} - JdbcTemplate操作数据库-批量修改和删除
//批量修改操作
public void batchUpdate(List users) {
String sql = "update t_user set user_name =?,status=? where id =?";
int[] ints = jdbcTemplate.batchUpdate(sql, users);
System.out.println(Arrays.asList(ints).toString());
}
//批量删除操作
public void batchDel(List users) {
String sql = "delete from t_user where id =?";
int[] ints = jdbcTemplate.batchUpdate(sql, users);
System.out.println(ints);
} 编写测试程序
//JdbcTemplate 批量修改操作
@Test
public void batchUpdate() {
ApplicationContext context = new ClassPathXmlApplicationContext("bean1.xml");
UserService userService = context.getBean("userServiceImpl", UserServiceImpl.class);
List list = new ArrayList();
Object[] o1 = {"namexiugai", 1, 4};
Object[] o2 = {"name2xiugai", 1, 5};
Object[] o3 = {"name3xiugai", 1, 6};
list.add(o1);
list.add(o2);
list.add(o3);
userService.batchUpdate(list);
}
//JdbcTemplate 批量删除操作
@Test
public void batchDel() {
ApplicationContext context = new ClassPathXmlApplicationContext("bean1.xml");
UserService userService = context.getBean("userServiceImpl", UserServiceImpl.class);
List list = new ArrayList();
Object[] o1 = {4};
Object[] o2 = {5};
Object[] o3 = {6};
list.add(o1);
list.add(o2);
list.add(o3);
userService.batchDel(list);
}