public interface BookShopDao {
    //根據(jù)書號(hào)獲取書的單價(jià)
    public int findBookPriceByIsbn(String isbn);
    //更新書的庫存，使書號(hào)對(duì)應(yīng)的庫存-1
    public void updateBookStock(String isbn);
    //更新用戶的賬戶余額：使username的balcance-price
    public void updateUserAccount(String username, int price);
   
}

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.jdbc.core.JdbcTemplate;
import org.springframework.stereotype.Repository;

@Repository("bookShopDao")
public class BookShopDaoImpl implements BookShopDao {

    @Autowired
    private JdbcTemplate JdbcTemplate;
   
    @Override
    public int findBookPriceByIsbn(String isbn) {
        String sql = "SELECT price FROM book WHERE isbn = ?";
       
        return JdbcTemplate.queryForObject(sql, Integer.class, isbn);
    }

    @Override
    public void updateBookStock(String isbn) {
        //檢查書的庫存是否足夠，若不夠，則拋出異常
        String sql2 = "SELECT stock FROM book_stock WHERE isbn = ?";
        int stock = JdbcTemplate.queryForObject(sql2, Integer.class, isbn);
        if (stock == 0) {
            throw new BookStockException("庫存不足！");
        }
        String sql = "UPDATE book_stock SET stock = stock - 1 WHERE isbn = ?";
        JdbcTemplate.update(sql, isbn);
    }

    @Override
    public void updateUserAccount(String username, int price) {
        //檢查余額是否不足，若不足，則拋出異常
        String sql2 = "SELECT balance FROM account WHERE username = ?";
        int balance = JdbcTemplate.queryForObject(sql2, Integer.class, username);
        if (balance < price) {
            throw new UserAccountException("余額不足！");
        }       
        String sql = "UPDATE account SET balance = balance - ? WHERE username = ?";
        JdbcTemplate.update(sql, price, username);
    }

}

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
import org.springframework.transaction.annotation.Isolation;
import org.springframework.transaction.annotation.Propagation;
import org.springframework.transaction.annotation.Transactional;

@Service("bookShopService")
public class BookShopServiceImpl implements BookShopService {

    @Autowired
    private BookShopDao bookShopDao;
   
    /**
     * 1.添加事務(wù)注解
     * 使用propagation 指定事務(wù)的傳播行為，即當(dāng)前的事務(wù)方法被另外一個(gè)事務(wù)方法調(diào)用時(shí)如何使用事務(wù)。
     * 默認(rèn)取值為REQUIRED，即使用調(diào)用方法的事務(wù)
     * REQUIRES_NEW：使用自己的事務(wù)，調(diào)用的事務(wù)方法的事務(wù)被掛起。
     *
     * 2.使用isolation 指定事務(wù)的隔離級(jí)別，最常用的取值為READ_COMMITTED
     * 3.默認(rèn)情況下 Spring 的聲明式事務(wù)對(duì)所有的運(yùn)行時(shí)異常進(jìn)行回滾，也可以通過對(duì)應(yīng)的屬性進(jìn)行設(shè)置。通常情況下，默認(rèn)值即可。
     * 4.使用readOnly 指定事務(wù)是否為只讀。 表示這個(gè)事務(wù)只讀取數(shù)據(jù)但不更新數(shù)據(jù)，這樣可以幫助數(shù)據(jù)庫引擎優(yōu)化事務(wù)。若真的是一個(gè)只讀取數(shù)據(jù)庫值得方法，應(yīng)設(shè)置readOnly=true
     * 5.使用timeOut 指定強(qiáng)制回滾之前事務(wù)可以占用的時(shí)間。
     */
    @Transactional(propagation=Propagation.REQUIRES_NEW,
            isolation=Isolation.READ_COMMITTED,
            noRollbackFor={UserAccountException.class},
            readOnly=true, timeout=3)
    @Override
    public void purchase(String username, String isbn) {
        //1.獲取書的單價(jià)
        int price = bookShopDao.findBookPriceByIsbn(isbn);
        //2.更新書的庫存
        bookShopDao.updateBookStock(isbn);
        //3.更新用戶余額
        bookShopDao.updateUserAccount(username, price);;
    }
}

    /**
     *
     */
    private static final long serialVersionUID = 1L;

    public BookStockException() {
        super();
        // TODO Auto-generated constructor stub
    }

    public BookStockException(String arg0, Throwable arg1, boolean arg2,
            boolean arg3) {
        super(arg0, arg1, arg2, arg3);
        // TODO Auto-generated constructor stub
    }

    public BookStockException(String arg0, Throwable arg1) {
        super(arg0, arg1);
        // TODO Auto-generated constructor stub
    }

    public BookStockException(String arg0) {
        super(arg0);
        // TODO Auto-generated constructor stub
    }

    public BookStockException(Throwable arg0) {
        super(arg0);
        // TODO Auto-generated constructor stub
    }
}

    /**
     *
     */
    private static final long serialVersionUID = 1L;

    public UserAccountException() {
        super();
        // TODO Auto-generated constructor stub
    }

    public UserAccountException(String arg0, Throwable arg1, boolean arg2,
            boolean arg3) {
        super(arg0, arg1, arg2, arg3);
        // TODO Auto-generated constructor stub
    }

    public UserAccountException(String arg0, Throwable arg1) {
        super(arg0, arg1);
        // TODO Auto-generated constructor stub
    }

    public UserAccountException(String arg0) {
        super(arg0);
        // TODO Auto-generated constructor stub
    }

    public UserAccountException(Throwable arg0) {
        super(arg0);
        // TODO Auto-generated constructor stub
    }
}

import java.util.List;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
import org.springframework.transaction.annotation.Transactional;

@Service("cashier")
public class CashierImpl implements Cashier {
    @Autowired
    private BookShopService bookShopService;
   
    @Transactional
    @Override
    public void checkout(String username, List<String> isbns) {
        for(String isbn : isbns) {
            bookShopService.purchase(username, isbn);
        }
    }
}

import java.util.Arrays;

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

public class SpringTransitionTest {
   
    private ApplicationContext ctx = null;
    private BookShopDao bookShopDao = null;
    private BookShopService bookShopService = null;
    private Cashier cashier = null;
    {
        ctx = new ClassPathXmlApplicationContext("applicationContext.xml");
        bookShopDao = ctx.getBean(BookShopDao.class);
        bookShopService = ctx.getBean(BookShopService.class);
        cashier = ctx.getBean(Cashier.class);
    }
   
    @Test
    public void testBookShopDaoFindPriceByIsbn() {
        System.out.println(bookShopDao.findBookPriceByIsbn("1001"));
    }

    @Test
    public void testBookShopDaoUpdateBookStock(){
        bookShopDao.updateBookStock("1001");
    }
   
    @Test
    public void testBookShopDaoUpdateUserAccount(){
        bookShopDao.updateUserAccount("AA", 100);
    }
    @Test
    public void testBookShopService(){
        bookShopService.purchase("AA", "1001");
    }
   
    @Test
    public void testTransactionPropagation(){
        cashier.checkout("AA", Arrays.asList("1001", "1002"));
    }
}