3. Java
// \src\com\atguigu\spring\jdbc\Department.java
package com.atguigu.spring.jdbc;
public class Department {
private Integer id;
private String name;
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;
}
@Override
public String toString() {
return "Department [id=" + id + ", name=" + name + "]";
}
}
// \src\com\atguigu\spring\jdbc\DepartmentDao.java
package com.atguigu.spring.jdbc;
import javax.sql.DataSource;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.jdbc.core.BeanPropertyRowMapper;
import org.springframework.jdbc.core.RowMapper;
import org.springframework.jdbc.core.support.JdbcDaoSupport;
import org.springframework.stereotype.Repository;
/**
* 不推荐使用 JdbcDaoSupport, 而推荐直接使用 JdbcTempate 作为 Dao 类的成员变量
*/
@Repository
public class DepartmentDao extends JdbcDaoSupport{
@Autowired
public void setDataSource2(DataSource dataSource){
setDataSource(dataSource);
}
public Department get(Integer id){
String sql = "SELECT id, dept_name name FROM departments WHERE id = ?";
RowMapper<Department> rowMapper = new BeanPropertyRowMapper<>(Department.class);
return getJdbcTemplate().queryForObject(sql, rowMapper, id);
}
}
// \src\com\atguigu\spring\jdbc\Employee.java
package com.atguigu.spring.jdbc;
public class Employee {
private Integer id;
private String lastName;
private String email;
private Integer dpetId;
public Integer getId() {
return id;
}
public void setId(Integer id) {
this.id = id;
}
public String getLastName() {
return lastName;
}
public void setLastName(String lastName) {
this.lastName = lastName;
}
public String getEmail() {
return email;
}
public void setEmail(String email) {
this.email = email;
}
public Integer getDpetId() {
return dpetId;
}
public void setDpetId(Integer dpetId) {
this.dpetId = dpetId;
}
@Override
public String toString() {
return "Employee [id=" + id + ", lastName=" + lastName + ", email="
+ email + ", dpetId=" + dpetId + "]";
}
}
// \src\com\atguigu\spring\jdbc\EmployeeDao.java
package com.atguigu.spring.jdbc;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.jdbc.core.BeanPropertyRowMapper;
import org.springframework.jdbc.core.JdbcTemplate;
import org.springframework.jdbc.core.RowMapper;
import org.springframework.stereotype.Repository;
@Repository
public class EmployeeDao {
@Autowired
private JdbcTemplate jdbcTemplate;
public Employee get(Integer id){
String sql = "SELECT id, last_name lastName, email FROM employees WHERE id = ?";
RowMapper<Employee> rowMapper = new BeanPropertyRowMapper<>(Employee.class);
Employee employee = jdbcTemplate.queryForObject(sql, rowMapper, id);
return employee;
}
}
// \src\com\atguigu\spring\jdbc\JDBCTest.java
package com.atguigu.spring.jdbc;
import java.sql.SQLException;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import javax.sql.DataSource;
import org.junit.Test;
import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;
import org.springframework.jdbc.core.BeanPropertyRowMapper;
import org.springframework.jdbc.core.JdbcTemplate;
import org.springframework.jdbc.core.RowMapper;
import org.springframework.jdbc.core.namedparam.BeanPropertySqlParameterSource;
import org.springframework.jdbc.core.namedparam.NamedParameterJdbcTemplate;
import org.springframework.jdbc.core.namedparam.SqlParameterSource;
public class JDBCTest {
private ApplicationContext ctx = null;
private JdbcTemplate jdbcTemplate;
private EmployeeDao employeeDao;
private DepartmentDao departmentDao;
private NamedParameterJdbcTemplate namedParameterJdbcTemplate;
{
ctx = new ClassPathXmlApplicationContext("applicationContext.xml");
jdbcTemplate = (JdbcTemplate) ctx.getBean("jdbcTemplate");
employeeDao = ctx.getBean(EmployeeDao.class);
departmentDao = ctx.getBean(DepartmentDao.class);
namedParameterJdbcTemplate = ctx.getBean(NamedParameterJdbcTemplate.class);
}
/**
* 使用具名参数时, 可以使用 update(String sql, SqlParameterSource paramSource) 方法进行更新操作
* 1. SQL 语句中的参数名和类的属性一致!
* 2. 使用 SqlParameterSource 的 BeanPropertySqlParameterSource 实现类作为参数.
*/
@Test
public void testNamedParameterJdbcTemplate2(){
String sql = "INSERT INTO employees(last_name, email, dept_id) "
+ "VALUES(:lastName,:email,:dpetId)";
Employee employee = new Employee();
employee.setLastName("XYZ");
employee.setEmail("xyz@sina.com");
employee.setDpetId(3);
SqlParameterSource paramSource = new BeanPropertySqlParameterSource(employee);
namedParameterJdbcTemplate.update(sql, paramSource);
}
/**
* 可以为参数起名字.
* 1. 好处: 若有多个参数, 则不用再去对应位置, 直接对应参数名, 便于维护
* 2. 缺点: 较为麻烦.
*/
@Test
public void testNamedParameterJdbcTemplate(){
String sql = "INSERT INTO employees(last_name, email, dept_id) VALUES(:ln,:email,:deptid)";
Map<String, Object> paramMap = new HashMap<>();
paramMap.put("ln", "FF");
paramMap.put("email", "ff@atguigu.com");
paramMap.put("deptid", 2);
namedParameterJdbcTemplate.update(sql, paramMap);
}
@Test
public void testDepartmentDao(){
System.out.println(departmentDao.get(1));
}
@Test
public void testEmployeeDao(){
System.out.println(employeeDao.get(1));
}
/**
* 获取单个列的值, 或做统计查询
* 使用 queryForObject(String sql, Class<Long> requiredType)
*/
@Test
public void testQueryForObject2(){
String sql = "SELECT count(id) FROM employees";
long count = jdbcTemplate.queryForObject(sql, Long.class);
System.out.println(count);
}
/**
* 查到实体类的集合
* 注意调用的不是 queryForList 方法
*/
@Test
public void testQueryForList(){
String sql = "SELECT id, last_name lastName, email FROM employees WHERE id > ?";
RowMapper<Employee> rowMapper = new BeanPropertyRowMapper<>(Employee.class);
List<Employee> employees = jdbcTemplate.query(sql, rowMapper,5);
System.out.println(employees);
}
/**
* 从数据库中获取一条记录, 实际得到对应的一个对象
* 注意不是调用 queryForObject(String sql, Class<Employee> requiredType, Object... args) 方法!
* 而需要调用 queryForObject(String sql, RowMapper<Employee> rowMapper, Object... args)
* 1. 其中的 RowMapper 指定如何去映射结果集的行, 常用的实现类为 BeanPropertyRowMapper
* 2. 使用 SQL 中列的别名完成列名和类的属性名的映射. 例如 last_name lastName
* 3. 不支持级联属性. JdbcTemplate 到底是一个 JDBC 的小工具, 而不是 ORM 框架
*/
@Test
public void testQueryForObject(){
String sql = "SELECT id, last_name lastName, email, dept_id as \"department.id\" FROM employees WHERE id = ?";
RowMapper<Employee> rowMapper = new BeanPropertyRowMapper<>(Employee.class);
Employee employee = jdbcTemplate.queryForObject(sql, rowMapper, 1);
System.out.println(employee);
}
/**
* 执行批量更新: 批量的 INSERT, UPDATE, DELETE
* 最后一个参数是 Object[] 的 List 类型: 因为修改一条记录需要一个 Object 的数组, 那么多条不就需要多个 Object 的数组吗
*/
@Test
public void testBatchUpdate(){
String sql = "INSERT INTO employees(last_name, email, dept_id) VALUES(?,?,?)";
List<Object[]> batchArgs = new ArrayList<>();
batchArgs.add(new Object[]{"AA", "aa@atguigu.com", 1});
batchArgs.add(new Object[]{"BB", "bb@atguigu.com", 2});
batchArgs.add(new Object[]{"CC", "cc@atguigu.com", 3});
batchArgs.add(new Object[]{"DD", "dd@atguigu.com", 3});
batchArgs.add(new Object[]{"EE", "ee@atguigu.com", 2});
jdbcTemplate.batchUpdate(sql, batchArgs);
}
/**
* 执行 INSERT, UPDATE, DELETE
*/
@Test
public void testUpdate(){
String sql = "UPDATE employees SET last_name = ? WHERE id = ?";
jdbcTemplate.update(sql, "Jack", 5);
}
@Test
public void testDataSource() throws SQLException {
DataSource dataSource = ctx.getBean(DataSource.class);
System.out.println(dataSource.getConnection());
}
}
// \src\com\atguigu\spring\tx\BookShopDao.java
package com.atguigu.spring.tx;
public interface BookShopDao {
//根据书号获取书的单价
public int findBookPriceByIsbn(String isbn);
//更新数的库存. 使书号对应的库存 - 1
public void updateBookStock(String isbn);
//更新用户的账户余额: 使 username 的 balance - price
public void updateUserAccount(String username, int price);
}
// \src\com\atguigu\spring\tx\BookShopDaoImpl.java
package com.atguigu.spring.tx;
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) {
//检查书的库存是否足够, 若不够, 则抛出异常
String sql2 = "SELECT stock FROM book_stock WHERE isbn = ?";
int stock = jdbcTemplate.queryForObject(sql2, Integer.class, isbn);
if(stock == 0){
throw new BookStockException("库存不足!");
}
String sql = "UPDATE book_stock SET stock = stock -1 WHERE isbn = ?";
jdbcTemplate.update(sql, isbn);
}
@Override
public void updateUserAccount(String username, int price) {
//验证余额是否足够, 若不足, 则抛出异常
String sql2 = "SELECT balance FROM account WHERE username = ?";
int balance = jdbcTemplate.queryForObject(sql2, Integer.class, username);
if(balance < price){
throw new UserAccountException("余额不足!");
}
String sql = "UPDATE account SET balance = balance - ? WHERE username = ?";
jdbcTemplate.update(sql, price, username);
}
}
// \src\com\atguigu\spring\tx\BookShopService.java
package com.atguigu.spring.tx;
public interface BookShopService {
public void purchase(String username, String isbn);
}
// \src\com\atguigu\spring\tx\BookShopServiceImpl.java
package com.atguigu.spring.tx;
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;
//添加事务注解
//1.使用 propagation 指定事务的传播行为, 即当前的事务方法被另外一个事务方法调用时
//如何使用事务, 默认取值为 REQUIRED, 即使用调用方法的事务
//REQUIRES_NEW: 事务自己的事务, 调用的事务方法的事务被挂起.
//2.使用 isolation 指定事务的隔离级别, 最常用的取值为 READ_COMMITTED
//3.默认情况下 Spring 的声明式事务对所有的运行时异常进行回滚. 也可以通过对应的
//属性进行设置. 通常情况下去默认值即可.
//4.使用 readOnly 指定事务是否为只读. 表示这个事务只读取数据但不更新数据,
//这样可以帮助数据库引擎优化事务. 若真的事一个只读取数据库值的方法, 应设置 readOnly=true
//5.使用 timeout 指定强制回滚之前事务可以占用的时间.
// @Transactional(propagation=Propagation.REQUIRES_NEW,
// isolation=Isolation.READ_COMMITTED,
// noRollbackFor={UserAccountException.class})
@Transactional(propagation=Propagation.REQUIRES_NEW,
isolation=Isolation.READ_COMMITTED,
readOnly=false,
timeout=3)
@Override
public void purchase(String username, String isbn) {
try {
Thread.sleep(5000);
} catch (InterruptedException e) {}
//1. 获取书的单价
int price = bookShopDao.findBookPriceByIsbn(isbn);
//2. 更新数的库存
bookShopDao.updateBookStock(isbn);
//3. 更新用户余额
bookShopDao.updateUserAccount(username, price);
}
}
// \src\com\atguigu\spring\tx\BookStockException.java
package com.atguigu.spring.tx;
public class BookStockException extends RuntimeException{
/**
*
*/
private static final long serialVersionUID = 1L;
public BookStockException() {
super();
// TODO Auto-generated constructor stub
}
public BookStockException(String message, Throwable cause,
boolean enableSuppression, boolean writableStackTrace) {
super(message, cause, enableSuppression, writableStackTrace);
// TODO Auto-generated constructor stub
}
public BookStockException(String message, Throwable cause) {
super(message, cause);
// TODO Auto-generated constructor stub
}
public BookStockException(String message) {
super(message);
// TODO Auto-generated constructor stub
}
public BookStockException(Throwable cause) {
super(cause);
// TODO Auto-generated constructor stub
}
}
// \src\com\atguigu\spring\tx\Cashier.java
package com.atguigu.spring.tx;
import java.util.List;
public interface Cashier {
public void checkout(String username, List<String> isbns);
}
// \src\com\atguigu\spring\tx\CashierImpl.java
package com.atguigu.spring.tx;
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);
}
}
}
// \src\com\atguigu\spring\tx\SpringTransactionTest.java
package com.atguigu.spring.tx;
import static org.junit.Assert.*;
import java.util.Arrays;
import org.junit.Test;
import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;
public class SpringTransactionTest {
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 testTransactionlPropagation(){
cashier.checkout("AA", Arrays.asList("1001", "1002"));
}
@Test
public void testBookShopService(){
bookShopService.purchase("AA", "1001");
}
@Test
public void testBookShopDaoUpdateUserAccount(){
bookShopDao.updateUserAccount("AA", 200);
}
@Test
public void testBookShopDaoUpdateBookStock(){
bookShopDao.updateBookStock("1001");
}
@Test
public void testBookShopDaoFindPriceByIsbn() {
System.out.println(bookShopDao.findBookPriceByIsbn("1001"));
}
}
// \src\com\atguigu\spring\tx\UserAccountException.java
package com.atguigu.spring.tx;
public class UserAccountException extends RuntimeException{
/**
*
*/
private static final long serialVersionUID = 1L;
public UserAccountException() {
super();
// TODO Auto-generated constructor stub
}
public UserAccountException(String message, Throwable cause,
boolean enableSuppression, boolean writableStackTrace) {
super(message, cause, enableSuppression, writableStackTrace);
// TODO Auto-generated constructor stub
}
public UserAccountException(String message, Throwable cause) {
super(message, cause);
// TODO Auto-generated constructor stub
}
public UserAccountException(String message) {
super(message);
// TODO Auto-generated constructor stub
}
public UserAccountException(Throwable cause) {
super(cause);
// TODO Auto-generated constructor stub
}
}
// \src\com\atguigu\spring\tx\xml\BookShopDao.java
package com.atguigu.spring.tx.xml;
public interface BookShopDao {
//根据书号获取书的单价
public int findBookPriceByIsbn(String isbn);
//更新数的库存. 使书号对应的库存 - 1
public void updateBookStock(String isbn);
//更新用户的账户余额: 使 username 的 balance - price
public void updateUserAccount(String username, int price);
}
// \src\com\atguigu\spring\tx\xml\BookShopDaoImpl.java
package com.atguigu.spring.tx.xml;
import org.springframework.jdbc.core.JdbcTemplate;
public class BookShopDaoImpl implements BookShopDao {
private JdbcTemplate jdbcTemplate;
public void setJdbcTemplate(JdbcTemplate jdbcTemplate) {
this.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) {
//检查书的库存是否足够, 若不够, 则抛出异常
String sql2 = "SELECT stock FROM book_stock WHERE isbn = ?";
int stock = jdbcTemplate.queryForObject(sql2, Integer.class, isbn);
if(stock == 0){
throw new BookStockException("库存不足!");
}
String sql = "UPDATE book_stock SET stock = stock -1 WHERE isbn = ?";
jdbcTemplate.update(sql, isbn);
}
@Override
public void updateUserAccount(String username, int price) {
//验证余额是否足够, 若不足, 则抛出异常
String sql2 = "SELECT balance FROM account WHERE username = ?";
int balance = jdbcTemplate.queryForObject(sql2, Integer.class, username);
if(balance < price){
throw new UserAccountException("余额不足!");
}
String sql = "UPDATE account SET balance = balance - ? WHERE username = ?";
jdbcTemplate.update(sql, price, username);
}
}
// \src\com\atguigu\spring\tx\xml\BookStockException.java
package com.atguigu.spring.tx.xml;
public class BookStockException extends RuntimeException{
/**
*
*/
private static final long serialVersionUID = 1L;
public BookStockException() {
super();
// TODO Auto-generated constructor stub
}
public BookStockException(String message, Throwable cause,
boolean enableSuppression, boolean writableStackTrace) {
super(message, cause, enableSuppression, writableStackTrace);
// TODO Auto-generated constructor stub
}
public BookStockException(String message, Throwable cause) {
super(message, cause);
// TODO Auto-generated constructor stub
}
public BookStockException(String message) {
super(message);
// TODO Auto-generated constructor stub
}
public BookStockException(Throwable cause) {
super(cause);
// TODO Auto-generated constructor stub
}
}
// \src\com\atguigu\spring\tx\xml\service\BookShopService.java
package com.atguigu.spring.tx.xml.service;
public interface BookShopService {
public void purchase(String username, String isbn);
}
// \src\com\atguigu\spring\tx\xml\service\Cashier.java
package com.atguigu.spring.tx.xml.service;
import java.util.List;
public interface Cashier {
public void checkout(String username, List<String> isbns);
}
// \src\com\atguigu\spring\tx\xml\service\impl\BookShopServiceImpl.java
package com.atguigu.spring.tx.xml.service.impl;
import com.atguigu.spring.tx.xml.BookShopDao;
import com.atguigu.spring.tx.xml.service.BookShopService;
public class BookShopServiceImpl implements BookShopService {
private BookShopDao bookShopDao;
public void setBookShopDao(BookShopDao bookShopDao) {
this.bookShopDao = bookShopDao;
}
@Override
public void purchase(String username, String isbn) {
try {
Thread.sleep(1000);
} catch (InterruptedException e) {}
//1. 获取书的单价
int price = bookShopDao.findBookPriceByIsbn(isbn);
//2. 更新数的库存
bookShopDao.updateBookStock(isbn);
//3. 更新用户余额
bookShopDao.updateUserAccount(username, price);
}
}
// \src\com\atguigu\spring\tx\xml\service\impl\CashierImpl.java
package com.atguigu.spring.tx.xml.service.impl;
import java.util.List;
import com.atguigu.spring.tx.xml.service.BookShopService;
import com.atguigu.spring.tx.xml.service.Cashier;
public class CashierImpl implements Cashier {
private BookShopService bookShopService;
public void setBookShopService(BookShopService bookShopService) {
this.bookShopService = bookShopService;
}
@Override
public void checkout(String username, List<String> isbns) {
for(String isbn: isbns){
bookShopService.purchase(username, isbn);
}
}
}
// \src\com\atguigu\spring\tx\xml\SpringTransactionTest.java
package com.atguigu.spring.tx.xml;
import java.util.Arrays;
import org.junit.Test;
import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;
import com.atguigu.spring.tx.xml.service.BookShopService;
import com.atguigu.spring.tx.xml.service.Cashier;
public class SpringTransactionTest {
private ApplicationContext ctx = null;
private BookShopDao bookShopDao = null;
private BookShopService bookShopService = null;
private Cashier cashier = null;
{
ctx = new ClassPathXmlApplicationContext("applicationContext-tx-xml.xml");
bookShopDao = ctx.getBean(BookShopDao.class);
bookShopService = ctx.getBean(BookShopService.class);
cashier = ctx.getBean(Cashier.class);
}
@Test
public void testTransactionlPropagation(){
cashier.checkout("AA", Arrays.asList("1001", "1002"));
}
@Test
public void testBookShopService(){
bookShopService.purchase("AA", "1001");
}
}
// \src\com\atguigu\spring\tx\xml\UserAccountException.java
package com.atguigu.spring.tx.xml;
public class UserAccountException extends RuntimeException{
/**
*
*/
private static final long serialVersionUID = 1L;
public UserAccountException() {
super();
// TODO Auto-generated constructor stub
}
public UserAccountException(String message, Throwable cause,
boolean enableSuppression, boolean writableStackTrace) {
super(message, cause, enableSuppression, writableStackTrace);
// TODO Auto-generated constructor stub
}
public UserAccountException(String message, Throwable cause) {
super(message, cause);
// TODO Auto-generated constructor stub
}
public UserAccountException(String message) {
super(message);
// TODO Auto-generated constructor stub
}
public UserAccountException(Throwable cause) {
super(cause);
// TODO Auto-generated constructor stub
}
}
