Spring JDBCTemplate & 声明式事务

1. JdbcTemplate是什么？

JdbcTemplate是spring框架中提供的一个模板对象，是对原始繁琐的Jdbc API对象的简单封装.

核心对象:

JdbcTemplate jdbcTemplate = new JdbcTemplate(DataSource dataSource);

核心方法:

int update(); 执行增、删、改语句

List<T>	query(); 查询多个
T queryForObject(); 查询一个
new BeanPropertyRowMapper<>(); 实现ORM映射封装

2. Spring整合JdbcTemplate

1) 创建java项目，导入坐标

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0"
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>

    <groupId>com.lagou</groupId>
    <artifactId>spring_jdbctemplate</artifactId>
    <version>1.0-SNAPSHOT</version>


    <dependencies>
        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
            <version>5.1.47</version>
        </dependency>
        <dependency>
            <groupId>com.alibaba</groupId>
            <artifactId>druid</artifactId>
            <version>1.1.15</version>
        </dependency>
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-context</artifactId>
            <version>5.1.5.RELEASE</version>
        </dependency>
        <dependency>
            <groupId>org.aspectj</groupId>
            <artifactId>aspectjweaver</artifactId>
            <version>1.8.13</version>
        </dependency>
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-jdbc</artifactId>
            <version>5.1.5.RELEASE</version>
        </dependency>
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-tx</artifactId>
            <version>5.1.5.RELEASE</version>
        </dependency>
        <dependency>
            <groupId>junit</groupId>
            <artifactId>junit</artifactId>
            <version>4.12</version>
        </dependency>
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-test</artifactId>
            <version>5.1.5.RELEASE</version>
        </dependency>
    </dependencies>

</project>

2）编写实体类

package com.lagou.domain;

public class Account {

    private Integer id;
    private String name;
    private Double money;

    @Override
    public String toString() {
        return "Account{" +
                "id=" + id +
                ", name='" + name + '\'' +
                ", money=" + money +
                '}';
    }

    public Integer getId() {
        return id;
    }

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

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public Double getMoney() {
        return money;
    }

    public void setMoney(Double money) {
        this.money = money;
    }
}

3）编写AccountDao接口和实现类

package com.lagou.dao;

import com.lagou.domain.Account;

import java.util.List;

public interface AccountDao {

    /*
        查询所有账户
     */
    public List<Account> findAll();

    /*
        根据ID查询账户
     */
    public Account findById(Integer id);

    /*
        添加账户
     */
    public void save(Account account);

    /*
        更新账户信息
     */
    public void update(Account account);

    /*
        根据ID删除账户
     */
    public void delete(Integer id);


}

package com.lagou.dao.impl;

import com.lagou.dao.AccountDao;
import com.lagou.domain.Account;
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 java.util.List;

@Repository
public class AccountDaoImpl implements AccountDao {

    @Autowired
    private JdbcTemplate jdbcTemplate;

    /*
        查询所有账户
     */
    public List<Account> findAll() {
        // 需要用到jdbcTemplate
        String sql = "select * from account";
        List<Account> list = jdbcTemplate.query(sql, new BeanPropertyRowMapper<Account>(Account.class));

        return list;
    }

    /*
        根据ID查询账户
     */
    public Account findById(Integer id) {
        String sql = "select * from account where id = ?";
        Account account = jdbcTemplate.queryForObject(sql, new BeanPropertyRowMapper<Account>(Account.class), id);
        return account;
    }

    /*
        添加账户
     */
    public void save(Account account) {
        String sql = "insert into account values(null,?,?)";
        jdbcTemplate.update(sql,account.getName(),account.getMoney());


    }

    /*
        更新账户
     */
    public void update(Account account) {
        String sql = "update account set money = ? where name = ?";
        jdbcTemplate.update(sql,account.getMoney(),account.getName());

    }

    /*
        根据ID删除账户
     */
    public void delete(Integer id) {
        String sql = "delete from account where id = ?";
        jdbcTemplate.update(sql,id);

    }
}

（4）编写AccountService接口和实现类

package com.lagou.servlet.impl;

import com.lagou.dao.AccountDao;
import com.lagou.domain.Account;
import com.lagou.servlet.AccountService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;

import java.util.List;

@Service
public class AccountSerivceImpl implements AccountService {

    @Autowired
    private AccountDao accountDao;


    public List<Account> findAll() {
        List<Account> all = accountDao.findAll();

        return all;
    }

    public Account findById(Integer id) {
        Account account = accountDao.findById(id);

        return account;
    }

    public void save(Account account) {

        accountDao.save(account);

    }

    public void update(Account account) {

        accountDao.update(account);

    }

    public void delete(Integer id) {

        accountDao.delete(id);

    }
}

（5）编写spring核心配置文件

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
       xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
       xmlns:context="http://www.springframework.org/schema/context"
       xsi:schemaLocation="
       	http://www.springframework.org/schema/beans
		http://www.springframework.org/schema/beans/spring-beans.xsd
       	http://www.springframework.org/schema/context
		http://www.springframework.org/schema/context/spring-context.xsd">


    <!--IOC注解扫描-->
    <context:component-scan base-package="com.lagou"/>

    <!--引入properties-->
    <context:property-placeholder location="classpath:jdbc.properties"/>

    <!--dataSource-->
    <bean id="dataSource" class="com.alibaba.druid.pool.DruidDataSource">
        <property name="driverClassName" value="${jdbc.driverClassName}"/>
        <property name="url" value="${jdbc.url}"/>
        <property name="username" value="${jdbc.username}"/>
        <property name="password" value="${jdbc.password}"/>
    </bean>


    <!--jdbcTemplate-->
    <bean id="jdbcTemplate" class="org.springframework.jdbc.core.JdbcTemplate">
        <constructor-arg name="dataSource" ref="dataSource"/>
    </bean>


</beans>

（6）测试类的编写

package com.lagou.test;

import com.lagou.domain.Account;
import com.lagou.servlet.AccountService;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.test.context.ContextConfiguration;
import org.springframework.test.context.junit4.SpringJUnit4ClassRunner;

import java.util.List;

@RunWith(SpringJUnit4ClassRunner.class)
@ContextConfiguration({"classpath:applicationContext.xml"})
public class AccountServiceImplTest {

    @Autowired
    private AccountService accountService;


    // 测试保存
    @Test
    public void testSave(){

        Account account = new Account();
        account.setName("lucy");
        account.setMoney(1000d);
        accountService.save(account);
    }

    // 测试查询所有
    @Test
    public void testFindAll(){

        List<Account> all = accountService.findAll();
        for (Account account : all) {
            System.out.println(account);
        }
    }

    //测试根据ID进行查询
    @Test
    public void testFindById(){

        Account account = accountService.findById(1);
        System.out.println(account);

    }


    // 测试账户修改
    @Test
    public void testUpdate(){

        Account account = new Account();
        account.setName("tom");
        account.setMoney(1000d);

        accountService.update(account);
    }

    // 测试根据ID删除账户
    @Test
    public void testDelete(){

        accountService.delete(4);
    }



}

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