SpringData JPA之Respository接口的使用

SpringData JPA之Respository接口的使用

Respository：最顶层的接口也是标志接口，目的是为了统一所有Repository的类型，且能让组件扫描的时候自动识别。
准备工作
导入JAR包：
别忘了导入Junit测试包，否则后面没法单元测试
编写Spring和数据库配置文件
applicationContext.xml文件

<?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:context="http://www.springframework.org/schema/context"
	xmlns:jdbc="http://www.springframework.org/schema/jdbc" 
	xmlns:aop="http://www.springframework.org/schema/aop"
	xmlns:tx="http://www.springframework.org/schema/tx"
	xmlns:jpa="http://www.springframework.org/schema/data/jpa"
	xsi:schemaLocation="
	http://www.springframework.org/schema/aop
	http://www.springframework.org/schema/aop/spring-aop.xsd
	http://www.springframework.org/schema/jdbc 
	http://www.springframework.org/schema/jdbc/spring-jdbc-4.3.xsd
	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-4.3.xsd
	http://www.springframework.org/schema/tx 
	http://www.springframework.org/schema/tx/spring-tx-4.3.xsd
	http://www.springframework.org/schema/data/jpa
	http://www.springframework.org/schema/data/jpa/spring-jpa.xsd"
		>
<!--开启JPA命名空间  -->
<!--读取数据库外置文件  -->
<context:property-placeholder location="classpath:jdbc.properties"/>
<!--配置数据库连接池  -->
<bean id="dataSource" class="com.mchange.v2.c3p0.ComboPooledDataSource">
<!--配置数据源链接  -->
<property name="jdbcUrl" value="${jdbc.url}"/>
<property name="driverClass" value="${jdbc.driver.class}"/>
<property name="user" value="${jdbc.username}"/>
<property name="password" value="${jdbc.password}"/>
</bean>
<!--配置EntityManagerFactory  -->
<bean id="entityManagerFactory" class="org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean">
<property name="dataSource" ref="dataSource"/>
<property name="jpaVendorAdapter">
<bean id="jpaVendorAdapter" class="org.springframework.orm.jpa.vendor.HibernateJpaVendorAdapter">
<!--配置数据库类型  -->
<property name="database" value="MYSQL"/>
<!--开启正向工程  -->
<property name="generateDdl" value="true"/>
<!--显示SQL的语句  -->
<property name="showSql" value="true"/>
</bean>
</property>
<!--设置HBM.XML的POJO映射  -->
<property name="packagesToScan">
<list>
<value>com.OVA.pojo</value>
</list>
</property>
</bean>
<!--开启事务管理  -->
<bean id="transactionManager" class="org.springframework.orm.jpa.JpaTransactionManager">
<property name="entityManagerFactory" ref="entityManagerFactory"/>
</bean>
<!--开启事务注解  -->
<tx:annotation-driven transaction-manager="transactionManager"/>
<!--开启Spring的注解扫描  -->
<context:component-scan base-package="com.OVA"/>
<!--Spring Data JPA配置  -->
<!--base-package扫描dao持久层接口所在的包 -->
<jpa:repositories base-package="com.OVA.dao"/>
</beans>

jdbc.properties

jdbc.url=jdbc:mysql:///springboot
jdbc.driver.class=com.mysql.jdbc.Driver
jdbc.username=root
jdbc.password=666888

代码编写
1. 创建POJO对象实现序列化

package com.OVA.pojo;

import java.io.Serializable;

import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.GenerationType;
import javax.persistence.Id;
import javax.persistence.Table;
@SuppressWarnings("serial")
@Entity
@Table(name = "users")
public class Users implements Serializable {
	@Id
	@GeneratedValue(strategy=GenerationType.IDENTITY)//设置主键自增
	@Column(name="userid")
	private Integer userid;
	@Column(name="username")
	private String username;
	@Column(name="userage")
	private Integer userage;

	public Integer getUserid() {
		return userid;
	}

	public void setUserid(Integer userid) {
		this.userid = userid;
	}

	public String getUsername() {
		return username;
	}

	public void setUsername(String username) {
		this.username = username;
	}

	public Integer getUserage() {
		return userage;
	}

	public void setUserage(Integer userage) {
		this.userage = userage;
	}

	@Override
	public int hashCode() {
		final int prime = 31;
		int result = 1;
		result = prime * result + ((userage == null) ? 0 : userage.hashCode());
		result = prime * result + ((userid == null) ? 0 : userid.hashCode());
		result = prime * result + ((username == null) ? 0 : username.hashCode());
		return result;
	}

	@Override
	public boolean equals(Object obj) {
		if (this == obj)
			return true;
		if (obj == null)
			return false;
		if (getClass() != obj.getClass())
			return false;
		Users other = (Users) obj;
		if (userage == null) {
			if (other.userage != null)
				return false;
		} else if (!userage.equals(other.userage))
			return false;
		if (userid == null) {
			if (other.userid != null)
				return false;
		} else if (!userid.equals(other.userid))
			return false;
		if (username == null) {
			if (other.username != null)
				return false;
		} else if (!username.equals(other.username))
			return false;
		return true;
	}

	@Override
	public String toString() {
		return "Users [userid=" + userid + ", username=" + username + ", userage=" + userage + "]";
	}

}

2. 创建POJO对象操作接口

package com.OVA.dao;

import java.util.List;

import org.springframework.data.jpa.repository.Modifying;
import org.springframework.data.jpa.repository.Query;
import org.springframework.data.repository.Repository;

import com.OVA.pojo.Users;

/**
 * @author OVA_Wom Repository 参数一：操作对象的类型；参数二：对象主键的类型
 **/
public interface UserDao extends Repository<Users, Integer> {
	// 方式一：使用Repository方法命名规则实现查询
	List<Users> findByUsername(String string);

	List<Users> findByUsernameLike(String string);

	List<Users> findByUsernameAndUserageGreaterThanEqual(String string, Integer userage);

	List<Users> findByUsernameLikeAndUserageGreaterThanEqual(String string, Integer userage);

	List<Users> findByUserageBetween(Integer userage1, Integer userage2);

	List<Users> findByUsernameOrderByUserageDesc(String string);

	// 方式二：通过@Quey注解JPQL语言进行查询
	// 参数顺序是从左至右一次绑定
	@Query(value = "from Users where username=?")
	List<Users> queryByUsername(String username);

	@Query("from Users where username like ?")
	List<Users> QueryUsernameLike(String username);

	@Query("from Users where username like ? and userage>?")
	List<Users> QueryUserage(String username, Integer userage);

	// 使用@Query注解SQL语句查询
	// nativeQuery=true设置使用原生的SQL语句进行查询
	@Query(value = "select * from users where username=?", nativeQuery = true)
	List<Users> queryByUsernameSQL(String username);

	@Query(value = "select * from users where username like ?", nativeQuery = true)
	List<Users> QueryUsernameLikeSQL(String username);

	@Query(value = "select * from users where username like ? and userage>?", nativeQuery = true)
	List<Users> QueryUserageSQL(String username, Integer userage);

	// @Query注解JPQL实现更新
	@Query("update Users set userage=? where userid=?")
	@Modifying
	int updateUserageByIdJPQL(Integer userage, Integer id);

	// @Query注解SQL实现更新
	@Query(value="update users set userage=? where userid=?",nativeQuery=true)
	@Modifying
	int updateUserageByIdSQL(Integer userage, Integer id);
}

3. 创建测试类进行测试

package test;

import java.util.List;

import org.junit.Test;
import org.junit.runner.RunWith;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.test.annotation.Rollback;
import org.springframework.test.context.ContextConfiguration;
import org.springframework.test.context.junit4.SpringJUnit4ClassRunner;
import org.springframework.transaction.annotation.Transactional;

import com.OVA.dao.UserDao;
import com.OVA.pojo.Users;

/**
 * @author OVA_Wom Repository测试接口
 */
@RunWith(SpringJUnit4ClassRunner.class)
@ContextConfiguration("classpath:applicationContext.xml")
public class RepositoryTest {
	@Autowired
	private UserDao userdao;

	// 用户名作为检索条件
	@Test
	@Transactional
	@Rollback(false)
	public void testName() {
		/*
		 * 判断相等的查询条件有三种表示方式 什么也不写默认 可以使用is 可以使用equal
		 */
		List<Users> findByUsernameIs = userdao.findByUsername("张三");
		for (Users u : findByUsernameIs) {
			System.out.println(u);
		}
	}

	// 根据用户的姓名做LIKE处理
	// Like条件关键字
	@Test
	@Transactional
	@Rollback(false)
	public void testLike() {
		List<Users> findByUsernameLike = userdao.findByUsernameLike("张%");
		for (Users u : findByUsernameLike) {
			System.out.println(u);
		}
	}

	// 多条件查询
	@Test
	@Transactional
	@Rollback(false)
	public void testNameAndAge() {
		List<Users> findByUsernameAndUserageGreaterThanEqual = userdao.findByUsernameAndUserageGreaterThanEqual("张三",
				12);
		for (Users u : findByUsernameAndUserageGreaterThanEqual) {
			System.out.println(u);
		}
	}

	// 多条件查询,姓名以张开头，年龄大于11的人
	@Test
	@Transactional
	@Rollback(false)
	public void testNameLikeAndAge() {
		List<Users> findByUsernameLikeAndUserageGreaterThanEqual = userdao
				.findByUsernameLikeAndUserageGreaterThanEqual("张%", 22);
		for (Users users : findByUsernameLikeAndUserageGreaterThanEqual) {
			System.out.println(users);
		}
	}

	// 查询用户按年龄区间
	@Test
	@Transactional
	@Rollback(false)
	public void testUserageBetween() {
		List<Users> findByUserageBetween = userdao.findByUserageBetween(11, 50);
		for (Users users : findByUserageBetween) {
			System.out.println(users);
		}
	}

	// 将下沟通姓名的用户按照年龄大小降序
	@Test
	@Transactional
	@Rollback(false)
	public void testUserageOrder() {
		List<Users> findByUsernameOrderByUserageDesc = userdao.findByUsernameOrderByUserageDesc("张三");
		for (Users users : findByUsernameOrderByUserageDesc) {
			System.out.println(users);
		}
	}

	// 使用@Queryd注解JPQL方式查询用户
	@Test
	@Transactional
	@Rollback(false)
	public void testQueryUsername() {
		List<Users> queryByUsername = userdao.queryByUsername("张三");
		for (Users users : queryByUsername) {
			System.out.println(users);
		}
	}

	// 使用@Queryd注解JPQL方式进行模糊查询
	@Test
	@Transactional
	@Rollback(false)
	public void testQueryUsernameLike() {
		List<Users> queryUsernameLike = userdao.QueryUsernameLike("张%");
		for (Users users : queryUsernameLike) {
			System.out.println(users);
		}
	}

	// 使用@Queryd注解JPQL方式进行多条件查询
	@Test
	@Transactional
	@Rollback(false)
	public void testQueryUserage() {
		List<Users> queryUserage = userdao.QueryUserage("张%", 20);
		for (Users users : queryUserage) {
			System.out.println(users);
		}
	}

	// 使用@Queryd注解SQL方式查询用户
	@Test
	@Transactional
	@Rollback(false)
	public void testQueryUsernameSQL() {
		List<Users> queryByUsernameSQL = userdao.queryByUsernameSQL("张三");
		for (Users users : queryByUsernameSQL) {
			System.out.println(users);
		}
	}

	// 使用@Queryd注解SQL方式进行模糊查询
	@Test
	@Transactional
	@Rollback(false)
	public void testQueryUsernameLikeSQL() {
		List<Users> queryUsernameLikeSQL = userdao.QueryUsernameLikeSQL("张%");
		for (Users users : queryUsernameLikeSQL) {
			System.out.println(users);
		}
	}

	// 使用@Queryd注解SQL方式进行多条件查询
	@Test
	@Transactional
	@Rollback(false)
	public void testQueryUserageSQL() {
		List<Users> queryUserageSQL = userdao.QueryUserageSQL("张%", 20);
		for (Users users : queryUserageSQL) {
			System.out.println(users);
		}
	}

	// 使用@Queryd注解JPQL方式进行数据更新
	@Test
	@Transactional
	@Rollback(false)
	public void testUpdateJPQL() {
		System.out.println(userdao.updateUserageByIdJPQL(111, 14));
	}

	// 使用@Queryd注解SQL方式进行数据更新
	@Test
	@Transactional
	@Rollback(false)
	public void testUpdateSQL() {
		System.out.println(userdao.updateUserageByIdSQL(11, 14));
	}
}

代码已经加详细的注释，以上就是Respository接口的基本内容，不足之处还请大神指正。