Spring学习笔记十六

Spring事务
ACID
原子性
一致性
隔离性
持久性

编程式/声明式
Spring事务管理抽象是PlatformTransactionManager
JDBC: DataSourceTransactionManager
JTA: JtaTransactionManager
Hibernate: HibernateTransactionManager

事务管理器以Bean形式声明在Spring IOC容器中

事务管理器

database: spring

create table book(
isbn varchar(50) primary key,
book_name varchar(50),
price int
);

create table account (
username varchar(50) primary key,
balance int,
check(balance >0 )
);

create table book_stock(
isbn varchar(50) primary key,
stock int
check(stock >0)
);

insert into book values(1001, 'java', 100);
insert into book values(1002, 'oracle', 70);
commit;

insert into account values('AA', 160);
commit;

insert into book_stock values(1001, 4);
insert into book_stock values(1002, 8);
commit;

1package springjdbc.tx;
2
3public interface IBookShopDao {
4    //根据isbn查找价格
5    public int findBookPriceByIsbn(String isbn);
6
7    //根据isbn更新库存-1
8    public void updateBookStock(String isbn);
9
10    //更新账号余额，balance - price
11    public void updateUserAccount(String userName, String price);
12}
13
14package springjdbc.tx;
15
16import org.springframework.beans.factory.annotation.Autowired;
17import org.springframework.jdbc.core.JdbcTemplate;
18import org.springframework.stereotype.Repository;
19
20@Repository("bookShopDao")
21public class BookShopDaoImple implements IBookShopDao {
22
23    @Autowired
24    private JdbcTemplate jdbcTemplate;
25
26    @Override
27    public int findBookPriceByIsbn(String isbn) {
28        String sql = "SELECT price FROM book WHERE isbn = ?";
29
30        return jdbcTemplate.queryForObject(sql, Integer.class, isbn);
31    }
32
33    @Override
34    public void updateBookStock(String isbn) {
35        String sql2 = "SELECT stock FROM book_stock WHERE isbn = ?";
36        int stock = jdbcTemplate.queryForObject(sql2, Integer.class, isbn);
37        if (stock == 0) {
38            throw new BookStockException("库存不足");
39        }
40        //检查书的库存，如果不够抛出异常
41        String sql = "UPDATE book_stock SET stock = stock -1 WHERE isbn = ?";
42        jdbcTemplate.update(sql,isbn);
43
44    }
45
46    @Override
47    public void updateUserAccount(String userName, String price) {
48        String sql2 = "SELECT balance FROM account WHERE username = ?";
49        int balance  = jdbcTemplate.queryForObject(sql2, Integer.class, userName);
50        if (balance < Integer.valueOf(price)) {
51            throw new UserAccountException("余额不足");
52        }
53        String sql = "UPDATE account SET balance = balance - ? WHERE userName = ?";
54        jdbcTemplate.update(sql, price, userName);
55    }
56}
57
58package springjdbc.tx;
59
60public interface IBookShopService {
61    public void purchase(String userName, String isbn);
62
63}
64
65package springjdbc.tx;
66
67import org.springframework.beans.factory.annotation.Autowired;
68import org.springframework.stereotype.Service;
69
70@Service("bookShopService")
71public class BookShopServiceImpl implements IBookShopService {
72    @Autowired
73    private IBookShopDao iBookShopDao;
74
75    @Override
76    public void purchase(String userName, String isbn) {
77        //get book price
78        iBookShopDao.findBookPriceByIsbn(isbn);
79
80        //update book stock
81        iBookShopDao.updateBookStock(isbn);
82
83        //update user account
84        iBookShopDao.updateUserAccount(userName, isbn);
85
86    }
87}
88
89package springjdbc.tx;
90
91import org.junit.Test;
92import org.springframework.context.ApplicationContext;
93import org.springframework.context.support.ClassPathXmlApplicationContext;
94
95public class TestTx {
96    private ApplicationContext ctx = null;
97
98    private IBookShopDao iBookShopDao;
99    private IBookShopService bookShopService;
100    {
101        ctx = new ClassPathXmlApplicationContext("springjdbc/application.xml");
102        iBookShopDao = ctx.getBean(IBookShopDao.class);
103        bookShopService = ctx.getBean(IBookShopService.class);
104    }
105
106    @Test
107    public void testBookShopService() {
108        bookShopService.purchase("AA", "100");
109    }
110
111    @Test
112    public void testBookShopDaoFindPriceByIsbn() {
113        System.out.println(iBookShopDao.findBookPriceByIsbn("1001"));
114    }
115
116    @Test
117    public void testBookShopDaoUpdateBookStock() {
118
119        iBookShopDao.updateBookStock("1001");
120    }
121
122    @Test
123    public void testBookShopDaoUserAccount() {
124        iBookShopDao.updateUserAccount("AA","1000" );
125    }
126}
127
128<?xml version="1.0" encoding="UTF-8"?>
129<beans xmlns="http://www.springframework.org/schema/beans"
130       xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
131       xmlns:context="http://www.springframework.org/schema/context"
132       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">
133
134    <context:component-scan base-package="springjdbc"></context:component-scan>
135    <!-- import resource files -->
136    <context:property-placeholder location="classpath:springjdbc/db.properties"></context:property-placeholder>
137
138    <!-- C3P0 DataSource -->
139    <bean id="dataSource" class="com.mchange.v2.c3p0.ComboPooledDataSource">
140        <property name="user" value="${jdbc.user}"/>
141        <property name="password" value="${jdbc.password}"/>
142        <property name="jdbcUrl" value="${jdbc.jdbcUrl}"/>
143        <property name="driverClass" value="${jdbc.driverClass}"/>
144        <property name="initialPoolSize" value="${jdbc.initPoolSize}"/>
145        <property name="maxPoolSize" value="${jdbc.maxPoolSize}"/>
146    </bean>
147
148    <!-- jdbc template -->
149    <bean id="jdbcTemplate" class="org.springframework.jdbc.core.JdbcTemplate">
150        <property name="dataSource" ref="dataSource"/>
151    </bean>
152
153    <!-- 具名参数 -->
154    <bean id="namedParameterJdbcTemplate" class="org.springframework.jdbc.core.namedparam.NamedParameterJdbcTemplate">
155        <constructor-arg ref="dataSource"/>
156    </bean>
157</beans>