Spring实现增删改查

桃扇骨 2022-01-23 13:49 404阅读 0赞

### 使用sping的Ioc的实现账户的CRUD(增删改查) ###

### 使用的知识点: ###

> QueryRunner:SQL语句的操作对象，可以设置查询结果集的封装策略
> 
> **创建方法：QueryRunner runner=new QueryRunner(dataSource)**
> 
> ResultSetHandler:封装数据的策略的对象
> 
> BeanHandler:将SQL查询的结果集转换成一个javaBean
> 
> **Account account=runner.query(sql,new BeanHandler<Account>(Account.class),3）；**
> 
> **BeanListHandler:****将SQL查询的结果集转换成一个集合的对象，集合中存储javaBean**
> 
> **用法：****list<Account> list=runner.query(sql,new BeanListHandler<Account>(Account.class));**

### **pom.xml中需要的依赖** ###

<dependencies>
        <dependency>
            <groupId>commons-dbutils</groupId>
            <artifactId>commons-dbutils</artifactId>
            <version>1.4</version>
        </dependency>
        
        <dependency>
            <groupId>c3p0</groupId>
            <artifactId>c3p0</artifactId>
            <version>0.9.1.2</version>
        </dependency>
        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
            <version>5.1.6</version>
        </dependency>
        <dependency>
            <groupId>junit</groupId>
            <artifactId>junit</artifactId>
            <version>4.12</version>
        </dependency>
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-context</artifactId>
            <version>5.0.2.RELEASE</version>
        </dependency>
    </dependencies>

### 创建数据库和编写的实体类 ###

表结构和数据

SQL语句

> **CREATE TABLE account(**
> 
> **id int primary key AUTO\_increment,**
> 
> **name varchar(40),**
> 
> **money float**
> 
> **);**
> 
> **insert into account(name,money) values('aaa',1000);  
> insert into account(name,money) values('bbb',1000);  
> insert into account(name,money) values('ccc',1000);**

### **账户的实体类Account(domain)** ###

package com.itheiam.domain;
    
    import lombok.Data;
    import lombok.ToString;
    
    import java.io.Serializable;
    @Data
    @ToString
    public class Account implements Serializable {
        private Integer id;
        private String name;
        private Float money;
    }

### 编写持久层（Dao） ###

/***
    *账户的持久层接口
    ***/
    public interface AccountDao {
    
        /**
         * 保存
         * @param account
         */
        void save(Account account);
    
        /**
         * 更新
         * @param account
         */
        void update(Account account);
    
        /**
         * 删除
         * @param accountId
         */
        void delete(Integer accountId);
    
        /**
         * 根据id查询
         * @param accountId
         * @return
         */
        Account findById(Integer accountId);
    
        /**
         * 查询所有
         * @return
         */
        List<Account> findAll();
    }

### 账户的持久层的实现类（AccountDaoImpl） ###

/***
    *账户的持久层接口实现类
    ***/
    public class AccountDaoImpl implements AccountDao {
    
        private QueryRunner runner;
    
        /**
         * 保存操作
         * @param account
         */
        public void save(Account account) {
            try {
                runner.update("insert into account(name,money)values(?,?)",account.getName(),account.getMoney());
            } catch (SQLException e) {
                e.printStackTrace();
            }
        }
    
        /***
         * 修改操作
         * @param account
         */
        public void update(Account account) {
            try {
                runner.update("update account set name=?,money=? where id=?",account.getName(),account.getMoney(),account.getId());
            } catch (SQLException e) {
                e.printStackTrace();
            }
        }
    
        /**
         * 删除操作
         * @param accountId
         */
        public void delete(Integer accountId) {
            try {
                runner.update("delete from account where id=?",accountId);
            } catch (SQLException e) {
                e.printStackTrace();
            }
        }
    
        /**
         * 根据ID查询
         * @param accountId
         * @return
         */
        public Account findById(Integer accountId) {
            try {
                return runner.query("select * from account where id=?",new BeanHandler<Account>(Account.class),accountId);
            } catch (SQLException e) {
                e.printStackTrace();
            }
            return  null;
        }
    
        /***
         * 查询所有
         * @return
         */
        public List<Account> findAll() {
            try {
                return runner.query("select * from account",new BeanListHandler<Account>(Account.class));
            } catch (SQLException e) {
                e.printStackTrace();
            }
            return  null;
        }
    
        /***
         * 注入QueryRunner对象
         * @param runner
         */
        public void setRunner(QueryRunner runner) {
            this.runner = runner;
        }
    }

### 编写业务层的接口（Service） ###

/****
    * 业务层接口
    ***/
    public interface AccountService {
    
        /**
         * 保存
         * @param account
         */
        void save(Account account);
    
        /**
         * 更新
         * @param account
         */
        void update(Account account);
    
        /**
         * 删除
         * @param accountId
         */
        void delete(Integer accountId);
    
        /**
         * 根据id查询
         * @param accountId
         * @return
         */
        Account findById(Integer accountId);
    
        /**
         * 查询所有
         * @return
         */
        List<Account> findAll();
    }

### 编写业务层实现类（AccountServiceImpl） ###

/****
    * 业务层接口实现类
    ***/
    public class AccountServiceImpl implements AccountService {
        private AccountDao accountDao;
    
        public void save(Account account) {
            accountDao.save(account);
        }
    
        public void update(Account account) {
            accountDao.update(account);
        }
    
        public void delete(Integer accountId) {
            accountDao.delete(accountId);
        }
    
        public Account findById(Integer accountId) {
            return accountDao.findById(accountId);
        }
    
        public List<Account> findAll() {
            return accountDao.findAll();
        }
    
        public void setAccountDao(AccountDao accountDao) {
            this.accountDao = accountDao;
        }

### 创建配置文件XML ###

<?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">
    
        
        <bean class="com.itheima.service.impl.AccountServiceImpl" id="accountService">
            <property name="accountDao" ref="accountDao" />
        </bean>
    
        
        <bean class="com.itheima.dao.impl.AccountDaoImpl" id="accountDao">
            <property name="runner" ref="runner" />
        </bean>
    
        
        <bean class="org.apache.commons.dbutils.QueryRunner" id="runner" scope="prototype">
            <constructor-arg name="ds" ref="dataSource" />
        </bean>
    
        
        <bean class="com.mchange.v2.c3p0.ComboPooledDataSource" id="dataSource">
            <property name="driverClass" value="com.mysql.jdbc.Driver" />
            <property name="jdbcUrl" value="jdbc:mysql://127.0.0.1:3306/spring5" />
            <property name="user" value="root" />
            <property name="password" value="123456" />
        </bean>
    </beans>

### 编写测试代码（Test） ###

public class AccountServiceTest {
    
        private AccountService accountService;
    
        @Before
        public void init(){
            ApplicationContext ac = new ClassPathXmlApplicationContext("bean.xml");
            accountService = ac.getBean(AccountService.class);
        }
    
        /**
         * 保存
         */
        @Test
        public void testSave(){
            Account account = new Account();
            account.setMoney(999f);
            account.setName("小红");
    
            accountService.save(account);
        }
    
        /**
         * 更新
         */
        @Test
        public void testUpdate(){
            //查询出id=3的账户，再修改
            Account account = accountService.findById(4);
            account.setName("zhangsan");
            //修改
            accountService.update(account);
        }
    
        /**
         * 删除
         */
        @Test
        public void testDelete(){
            Integer accountId=3;
            accountService.delete(accountId);
        }
    
        /**
         * 根据id查询
         * @return
         */
        @Test
        public void testFindById(){
            Integer accountId=3;
            Account account = accountService.findById(accountId);
            System.out.println(account);
        }
    
        /**
         * 查询所有
         * @return
         */
        @Test
        public void testFindAll(){
            List<Account> accounts = accountService.findAll();
            for (Account account : accounts) {
                System.out.println(account);
            }
        }
    }