SpringData 第一章：简单开发和注解开发

一、SpringData简介

二、开发第一个SpringData程序

1、创建一个普通maven，过程省略（不懂可见maven的文章）

2.修改pox.xml的文件内容

		<!--Mysql 驱动包 -->
		<dependency>
			<groupId>mysql</groupId>
			<artifactId>mysql-connector-java</artifactId>
			<version>5.1.38</version>
		</dependency>
		<!-- https://mvnrepository.com/artifact/org.springframework.data/spring-data-jpa -->
		<dependency>
			<groupId>org.springframework.data</groupId>
			<artifactId>spring-data-jpa</artifactId>
			<version>1.11.6.RELEASE</version>
		</dependency>
		<!-- https://mvnrepository.com/artifact/org.hibernate/hibernate-entitymanager -->
		<dependency>
			<groupId>org.hibernate</groupId>
			<artifactId>hibernate-entitymanager</artifactId>
			<version>5.2.9.Final</version>
		</dependency>

3、定义全局文件SpringData.xml文件

<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"
       xmlns:tx="http://www.springframework.org/schema/tx"
       xmlns:jpa="http://www.springframework.org/schema/data/jpa"
       xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd
        http://www.springframework.org/schema/data/jpa http://www.springframework.org/schema/data/jpa/spring-jpa-1.3.xsd
        http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx-4.0.xsd
        http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-4.0.xsd">
     <context:component-scan base-package="com.mingde"/>
     <!--1、 配置数据源 -->   
     <bean id="dataSource" class="org.springframework.jdbc.datasource.DriverManagerDataSource">
     	<property name="driverClassName" value="com.mysql.jdbc.Driver"/>
     	<property name="url" value="jdbc:mysql:///springdata"/>
     	<property name="username" value="root"/>
     	<property name="password" value="123"/>
     </bean>   
     <!-- 2、配置实体类管理工厂 -->
     <bean id="entityManagerFactory" class="org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean">
     	<property name="dataSource" ref="dataSource"/>
     	<property name="jpaVendorAdapter">
     		<bean class="org.springframework.orm.jpa.vendor.HibernateJpaVendorAdapter"/>
     	</property>
     	<property name="packagesToScan" value="com.mingde"/>
     	<property name="jpaProperties">
     		<props>
     			<prop key="hibernate.ejb.naming_strategy">org.hibernate.cfg.ImprovedNamingStrategy</prop>
                <prop key="hibernate.dialect">org.hibernate.dialect.MySQL5InnoDBDialect</prop>
                <prop key="hibernate.show_sql">true</prop>
                <prop key="hibernate.format_sql">true</prop>
                <prop key="hibernate.hbm2ddl.auto">update</prop>
     		</props>
     	</property>
     </bean>
     <!-- 3、配置事务管理器 -->
     <bean id="transactionManager" class="org.springframework.orm.jpa.JpaTransactionManager">
		<property name="entityManagerFactory" ref="entityManagerFactory"/>
     </bean>
     <!-- 4.配置以注解的方式定义事务 -->
    <tx:annotation-driven transaction-manager="transactionManager"/>
    
    <!-- 5.配置jpa:repositories -->
    <jpa:repositories base-package="com.mingde" entity-manager-factory-ref="entityManagerFactory"/>
</beans>

4、实体类

package com.mingde.po;

import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.GenerationType;
import javax.persistence.Id;

@Entity
public class Student {

	@Id
	@GeneratedValue(strategy=GenerationType.IDENTITY)
	private int sid;
	private String sname;
	private String sex;
	private int age;
	private String addr;
	
	/*** get、set和toString 作者在此省略  **/
}

5、dao层：自定义方法的命名规则

public interface StudentRepository extends Repository<Student, Integer> {//参数一：要映射的类，参数二：该表的主键的类型
	/** 这里只需写接口，不需要有实现类 **/

	/*** 下面的方法名是按照下面的‘自定义方法的命名规则表’来命名的，不是随便乱命名的 ***/

	//根据姓名查询学生信息
	List<Student> findBySname(String sname)throws Exception;
	//模糊查询
	List<Student> findBySnameLike(String sname)throws Exception;
	//查询性别和年龄大于多少岁的
	List<Student> findBySexAndAgeGreaterThan(String sex ,int age)throws Exception;
	//查询一某个字开头的（如某个地址是以‘上’开头的：上海）
	List<Student> findByAddrStartingWith(String saddr)throws Exception;
	//查询指定性别并且按年龄升序排序
	List<Student> findBySexOrderByAge(String sex)throws Exception;
}

自定义方法的命名规则表：

6、测试类

import java.util.List;

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

import com.mingde.dao.StudentRepository;
import com.mingde.po.Student;
import com.mingde.service.StudentService;

public class Test {

	private ApplicationContext ac;
	private StudentRepository sr;
	
	@Before
	public void setUp() throws Exception {
		ac=new ClassPathXmlApplicationContext("SpringData.xml");
		sr=ac.getBean(StudentRepository.class);
	}

	@org.junit.Test
	public void test() {
		System.out.println("开始了");
	}
	//查询叫‘张三’的所有学生
	@org.junit.Test
	public void test2() throws Exception {
		List<Student> findBySname = sr.findBySname("张三");
		System.out.println(findBySname);
	}
	//模糊查询姓名带‘张’的所有学生
	@org.junit.Test
	public void test3() throws Exception {
		List<Student> findBySname = sr.findBySnameLike("%张%");
		System.out.println(findBySname);
	}
	//查询所有男生并且年龄大于12岁的
	@org.junit.Test
	public void test4() throws Exception {
		List<Student> findBySname = sr.findBySexAndAgeGreaterThan("男",12);
		System.out.println(findBySname);
	}
	//查询地址中以‘上’开头的
	@org.junit.Test
	public void test5() throws Exception {
		List<Student> findBySname = sr.findByAddrStartingWith("上");
		System.out.println(findBySname);
	}
	//查询指定性别并且按年龄升序排序
	@org.junit.Test
	public void test6() throws Exception {
		List<Student> findBySname = sr.findBySexOrderByAge("男");
		System.out.println(findBySname);
	}
}

三、利用注解@Query及@Modifying来进行开发

1.pom.xml和SpringData.xml和实体类同上

2.定义Dao层

package com.mingde.dao;

import java.util.List;

import org.springframework.data.jpa.repository.Modifying;
import org.springframework.data.jpa.repository.Query;
import org.springframework.data.repository.RepositoryDefinition;
import org.springframework.data.repository.query.Param;

import com.mingde.po.Student;

//自主命名查询方法
@RepositoryDefinition(domainClass=Student.class,idClass=Integer.class) //可以替代下面的extends。。
public interface StudentRepository2 /*extends Repository<Student, Integer>*/{

	//查询所有
	@Query("select st from Student st") //这里不能写成select * from student，不能拥有*号
	public List<Student> findAll() throws Exception;
	
	//根据姓名进行模糊查询
	@Query("select st from Student st where st.sname like %?1%")
	public List<Student> findByWords(String words) throws Exception;
	
	//修改学生
	@Modifying			//代表可以修改
	@Query("update Student st set st.sname=:sname,st.addr=:addr where st.sid=:sid")
	public void updateStudent(@Param("sname")String sname,
			@Param("addr")String addr,
			@Param("sid") int sid) throws Exception;
	
	
}

3、定义Service层

package com.mingde.service;

import javax.transaction.Transactional;

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

import com.mingde.dao.StudentRepository2;

@Service
public class StudentService {
	
	@Autowired			//在junit是不可以使用该注解的，因为spring无法扫描Junit的test文件
	private StudentRepository2 sr;
	@Transactional
	public void updateStudent(String sname,String addr,int sid) throws Exception {
		sr.updateStudent(sname, addr, sid);
	}
}

4、测试类

package com.mingde.test;

import java.util.List;

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

import com.mingde.dao.StudentRepository;
import com.mingde.dao.StudentRepository2;
import com.mingde.po.Student;
import com.mingde.service.StudentService;

public class Test {

	private ApplicationContext ac;
	private StudentRepository2 sr2;
	@Before
	public void setUp() throws Exception {
		ac=new ClassPathXmlApplicationContext("SpringData.xml");
		sr2=ac.getBean(StudentRepository2.class);
	}

	
	/**   利用注解@Query及@Modifying   **/
	@org.junit.Test
	public void test7() throws Exception {
		List<Student> findAll = sr2.findAll();
		System.out.println(findAll);
		
	}
	public static void main(String[] args) throws Exception {
		ApplicationContext ac2=new ClassPathXmlApplicationContext("SpringData.xml");
		StudentRepository2 sr2=ac2.getBean(StudentRepository2.class);
		StudentService ss=ac2.getBean(StudentService.class);
		/*//查询所有学生
		List<Student> findAll = sr2.findAll();
		System.out.println(findAll);
		//模糊查询学生
		List<Student> findByWords = sr2.findByWords("张");
		System.out.println(findByWords);*/
		//修改学生信息
		ss.updateStudent("郑秋冬", "杭州", 1002);
		
	}
	
	
}

注意：@Query和@Modifying不能进行添加（insert）操作