Spring框架——事务管理方式搭建一个小的项目

学习Spring框架，通过事务管理的方式搭建一个小的项目，该项目可以查询对数据库中的图书库存数量进行修改。

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首先，使用MVC分层的设计模式思想搭建项目目录结构。

此部分代码源码之中都有相关注释，所以尽情附上源码。

首先Dao层的源码：

package com.jredu.book.Dao;

public interface BookDao {

    /**
     * 通过编号查询书的价格
     * @param isbn
     * @return
     */
    int findBookPriceByIsbn(String isbn);

    /**
     * 通过用户名查询余额
     * @param username
     * @return
     */
    int findBalanceByUsername(String username);

    /**
     * 更新书的库存
     * @param isbn
     */
    void updateBookStock(String isbn,int stock);

    /**
     * 通过编号查询库存数量
     * @param isbn
     * @return
     */
    int findStockByIsbn(String isbn);

    /**
     * 更新用户余额信息
     * @param username
     * @param price
     */
    void updateAccountBalance(String username,int price);
}

dao.impl相关的源码：

package com.jredu.book.Dao.Impl;

import java.util.Map;

import javax.sql.DataSource;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.jdbc.core.support.JdbcDaoSupport;
import org.springframework.stereotype.Repository;
import org.springframework.stereotype.Service;

import com.jredu.book.Dao.BookDao;
import com.jredu.book.entity.Account;
import com.jredu.book.entity.Book;

@Repository
public class BookDaoImpl extends JdbcDaoSupport implements BookDao{

    @Autowired
    public void setDS(DataSource dataSource){
        setDataSource(dataSource);
    }

    @Override
    public int findStockByIsbn(String isbn) {
        // TODO Auto-generated method stub
        String sql = "select * from book_stock where isbn=?";
        Map<String, Object> bookStock= getJdbcTemplate().queryForMap(sql,isbn);
        int stock = Integer.parseInt(bookStock.get("stock").toString());
        return stock;
    }

    @Override
    public int findBookPriceByIsbn(String isbn) {
        // TODO Auto-generated method stub
        String sql="select * from book where isbn=?";
        Book book = getJdbcTemplate().queryForObject(sql, new Book(), isbn);
        return book.getPrice();
    }

    @Override
    public int findBalanceByUsername(String username) {
        // TODO Auto-generated method stub
        String sql = "select * from account where username=?";
        Account account = getJdbcTemplate().queryForObject(sql, new Account(),username);
        return account.getBalance();
    }

    @Override
    public void updateBookStock(String isbn,int stock) {
        // TODO Auto-generated method stub
        String sql="update book_stock set stock=? where isbn=?";
        getJdbcTemplate().update(sql,stock,isbn);

    }

    @Override
    public void updateAccountBalance(String username, int price) {
        // TODO Auto-generated method stub
        String sql="update account set balance=? where username=?";
        getJdbcTemplate().update(sql,price,username);
    }

}

entity实体类的相关源码：

package com.jredu.book.entity;

import java.sql.ResultSet;
import java.sql.SQLException;

import org.springframework.jdbc.core.RowMapper;

public class Account implements RowMapper<Account>{

    private String username;
    private int balance;
    public String getUsername() {
        return username;
    }
    public void setUsername(String username) {
        this.username = username;
    }
    public int getBalance() {
        return balance;
    }
    public void setBalance(int balance) {
        this.balance = balance;
    }
    @Override
    public Account mapRow(ResultSet rs, int arg1) throws SQLException {
        // TODO Auto-generated method stub
        Account account = new Account();
        account.setUsername(rs.getString("username"));
        account.setBalance(rs.getInt("balance"));
        return account;
    }

}

package com.jredu.book.entity;

import java.sql.ResultSet;
import java.sql.SQLException;

import org.springframework.jdbc.core.RowMapper;

public class Book implements RowMapper<Book>{

    private String isbn;
    private String bookName;
    private int price;
    public String getIsbn() {
        return isbn;
    }
    public void setIsbn(String isbn) {
        this.isbn = isbn;
    }
    public String getBookName() {
        return bookName;
    }
    public void setBookName(String bookName) {
        this.bookName = bookName;
    }
    public int getPrice() {
        return price;
    }
    public void setPrice(int price) {
        this.price = price;
    }
    @Override
    public Book mapRow(ResultSet rs, int arg1) throws SQLException {
        // TODO Auto-generated method stub
        Book book = new Book();
        book.setIsbn(rs.getString("isbn"));
        book.setBookName(rs.getString("book_name"));
        book.setPrice(rs.getInt("price"));
        return book;
    }

}

service目录下的相关源码：

package com.jredu.book.service;

public interface BookService {

    void purchase(String isbn,String username);
}

package com.jredu.book.service;

public interface MoneyService {

    void purchase(String isbn,String username);
}

service接口即service.impl目录下的相关源码：

package com.jredu.book.service.Impl;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Repository;

import com.jredu.book.Dao.BookDao;
import com.jredu.book.service.BookService;
@Repository
public class BookServiceImpl implements BookService{

    @Autowired
    private BookDao dao;

    @Override
    public void purchase(String isbn, String username) {
        // TODO Auto-generated method stub
        int stock = dao.findStockByIsbn(isbn);
        //库存要大于1本
        if(stock>0){
            int price = dao.findBookPriceByIsbn(isbn);
            int balance = dao.findBalanceByUsername(username);
            //余额是否大于书的价格
            if(balance>=price){
                //执行更新余额信息
                dao.updateAccountBalance(username, balance-price);
                //更新库存信息
                dao.updateBookStock(isbn, stock-1);
            }
        }
    }

}

编写一个测试类,book.test目录下测试类源码：

package com.jredu.book.test;

import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;

import com.jredu.book.service.BookService;
import com.jredu.book.service.MoneyService;

public class BookTest {

    public static void main(String[] args) {
        ApplicationContext app= new ClassPathXmlApplicationContext("applicationContext-book.xml");
        BookService service = app.getBean(BookService.class);
        service.purchase("abc","wang");
        System.out.println("业务完成");

    }
}

最重要的部分是配置application-book.xml的相关配置信息，相关注释代码之中含有，附上源码：

<?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:p="http://www.springframework.org/schema/p"
    xmlns:aop="http://www.springframework.org/schema/aop"
    xmlns:tx="http://www.springframework.org/schema/tx"
    xmlns:context="http://www.springframework.org/schema/context"
    xmlns:mvc="http://www.springframework.org/schema/mvc"
    xmlns:util="http://www.springframework.org/schema/util"
    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
        http://www.springframework.org/schema/util
        http://www.springframework.org/schema/util/spring-util.xsd
        http://www.springframework.org/schema/aop
        http://www.springframework.org/schema/aop/spring-aop.xsd
        http://www.springframework.org/schema/tx
        http://www.springframework.org/schema/tx/spring-tx.xsd
        http://www.springframework.org/schema/mvc
        http://www.springframework.org/schema/mvc/spring-mvc.xsd">
    <!-- 自动扫描 -->
    <context:component-scan base-package="com.jredu.book"></context:component-scan>
    <!-- 配置C3P0数据源 -->
    <!-- 导入资源文件 -->
    <context:property-placeholder location="classpath:jdbc.properties"/>
    <bean
        id="dataSource" class="com.mchange.v2.c3p0.ComboPooledDataSource"
        p:user="${jdbc.user}"
        p:password="${jdbc.pwd}"
        p:driverClass="${jdbc.driverClassName}"
        p:jdbcUrl="${jdbc.url}"
        p:initialPoolSize="${jdbc.initPoolSize}"
        p:maxPoolSize="${jdbc.maxPoolSize}"
    />
    <!-- 配置事务管理器 -->
    <bean
    id="transactionManager" class="org.springframework.jdbc.datasource.DataSourceTransactionManager"
    p:dataSource-ref="dataSource"
    />
    <!-- 事务的通知 -->
    <tx:advice
        id="booktxAdvice" transaction-manager="transactionManager"
        >
        <tx:attributes>
            <tx:method name="purchase*" propagation="REQUIRED"/>
        </tx:attributes>
    </tx:advice>

    <aop:config>
        <aop:pointcut expression="execution (* com.jredu.book.service.*.*(..))" id="pointcut"/>
        <aop:advisor advice-ref="booktxAdvice" pointcut-ref="pointcut"/>
    </aop:config>

    <!-- 配置JDBC Template -->
    <bean
        id="jdbcTemplate"
        class="org.springframework.jdbc.core.JdbcTemplate"
        p:dataSource-ref="dataSource"
    />

</beans>

至此，使用事务方式搭建的一个小项目就已经完成，操作完成后，数据库中的图书库存数量会有所变化。