SpringJpaDate

　　　　　　　　　　　　　　　　　　SpringDataJpa

什么是SpringDataJpa:基于springjpa简化的框架

　　　　　　更方便更简单的对数据库进行crud操作

　　　　　　SpringDataJpa提供的接口：JpaRepository

　　　　　　JpaRepository接口的底层已经定义好了一些简单的crud方法

 

使用SpringDataJpa首先进行导包：

 

<dependencies>
    <!-- Spring的支持包 -->
    <dependency>
        <groupId>org.springframework</groupId>
        <artifactId>spring-core</artifactId>
        <version>${org.springframework.version}</version>
    </dependency>
    <dependency>
        <groupId>org.springframework</groupId>
        <artifactId>spring-context</artifactId>
        <version>${org.springframework.version}</version>
    </dependency>
    <dependency>
        <groupId>org.springframework</groupId>
        <artifactId>spring-context-support</artifactId>
        <version>${org.springframework.version}</version>
    </dependency>

    <dependency>
        <groupId>org.springframework</groupId>
        <artifactId>spring-tx</artifactId>
        <version>${org.springframework.version}</version>
    </dependency>
    <dependency>
        <groupId>org.springframework</groupId>
        <artifactId>spring-jdbc</artifactId>
        <version>${org.springframework.version}</version>
    </dependency>
    <dependency>
        <groupId>org.springframework</groupId>
        <artifactId>spring-orm</artifactId>
        <version>${org.springframework.version}</version>
    </dependency>
    <dependency>
        <groupId>org.springframework</groupId>
        <artifactId>spring-aop</artifactId>
        <version>${org.springframework.version}</version>
    </dependency>
    <dependency>
        <groupId>org.springframework</groupId>
        <artifactId>spring-test</artifactId>
        <version>${org.springframework.version}</version>
        <scope>test</scope>
    </dependency>
    <!-- 引入web前端的支持 -->
    <dependency>
        <groupId>org.springframework</groupId>
        <artifactId>spring-web</artifactId>
        <version>${org.springframework.version}</version>
    </dependency>
    <dependency>
        <groupId>org.springframework</groupId>
        <artifactId>spring-webmvc</artifactId>
        <version>${org.springframework.version}</version>
    </dependency>
    <!-- SpringMCV上传需要用到io包-->
    <dependency>
        <groupId>org.apache.commons</groupId>
        <artifactId>commons-io</artifactId>
        <version>1.3.2</version>
    </dependency>
    <!-- 文件上传用到的包 -->
    <dependency>
        <groupId>commons-fileupload</groupId>
        <artifactId>commons-fileupload</artifactId>
        <version>1.2.2</version>
    </dependency>
    <!-- SpringMVC的json支持包 -->
    <dependency>
        <groupId>com.fasterxml.jackson.core</groupId>
        <artifactId>jackson-core</artifactId>
        <version>${com.fasterxml.jackson.version}</version>
    </dependency>
    <dependency>
        <groupId>com.fasterxml.jackson.core</groupId>
        <artifactId>jackson-annotations</artifactId>
        <version>${com.fasterxml.jackson.version}</version>
    </dependency>
    <dependency>
        <groupId>com.fasterxml.jackson.core</groupId>
        <artifactId>jackson-databind</artifactId>
        <version>${com.fasterxml.jackson.version}</version>
    </dependency>
    <!-- hibernate的支持包 -->
    <dependency>
        <groupId>org.hibernate</groupId>
        <artifactId>hibernate-core</artifactId>
        <version>${org.hibernate.version}</version>
    </dependency>
    <dependency>
        <groupId>org.hibernate</groupId>
        <artifactId>hibernate-entitymanager</artifactId>
        <version>${org.hibernate.version}</version>
    </dependency>
    <!-- SpringData的支持包 -->
    <dependency>
        <groupId>org.springframework.data</groupId>
        <artifactId>spring-data-jpa</artifactId>
        <version>${spring-data-jpa.version}</version>
    </dependency>
    <!-- SpringData的擴展包 -->
    <dependency>
        <groupId>com.github.wenhao</groupId>
        <artifactId>jpa-spec</artifactId>
        <version>3.1.1</version>
        <!-- 把所有的依賴都去掉 -->
        <exclusions>
            <exclusion>
                <groupId>*</groupId>
                <artifactId>*</artifactId>
            </exclusion>
        </exclusions>
    </dependency>

    <dependency>
        <groupId>commons-dbcp</groupId>
        <artifactId>commons-dbcp</artifactId>
        <version>1.2.2</version>
    </dependency>

    <dependency>
        <groupId>mysql</groupId>
        <artifactId>mysql-connector-java</artifactId>
        <version>5.1.6</version>
    </dependency>

    <dependency>
        <groupId>org.apache.commons</groupId>
        <artifactId>commons-lang3</artifactId>
        <version>3.5</version>
    </dependency>
    <!-- 測試包 -->
    <dependency>
        <groupId>junit</groupId>
        <artifactId>junit</artifactId>
        <version>4.12</version>
        <scope>test</scope>
    </dependency>
    <dependency>
        <groupId>javax.servlet</groupId>
        <artifactId>javax.servlet-api</artifactId>
        <version>3.1.0</version>
        <!-- 这个scope 只能作用在编译和测试时，同时没有传递性。表示在运行的时候不添加此jar文件 -->
        <scope>provided</scope>
    </dependency>
    <!-- 日志文件 -->
    <dependency>
        <groupId>org.slf4j</groupId>
        <artifactId>slf4j-api</artifactId>
        <version>${org.slf4j.version}</version>
    </dependency>
    <dependency>
        <groupId>org.slf4j</groupId>
        <artifactId>slf4j-log4j12</artifactId>
        <version>${org.slf4j.version}</version>
        <scope>runtime</scope>
    </dependency>
    <dependency>
        <groupId>log4j</groupId>
        <artifactId>log4j</artifactId>
        <version>1.2.14</version>
    </dependency>
    <!-- 代码生成器模版技术 -->
    <dependency>
        <groupId>org.apache.velocity</groupId>
        <artifactId>velocity</artifactId>
        <version>1.6</version>
    </dependency>
    <!-- shiro的支持包 -->
    <dependency>
        <groupId>org.apache.shiro</groupId>
        <artifactId>shiro-all</artifactId>
        <version>1.4.0</version>
        <type>pom</type>
    </dependency>
    <!-- shiro与Spring的集成包 -->
    <dependency>
        <groupId>org.apache.shiro</groupId>
        <artifactId>shiro-spring</artifactId>
        <version>1.4.0</version>
    </dependency>
    <!-- poi支持的jar包 -->
    <dependency>
        <groupId>org.apache.poi</groupId>
        <artifactId>poi</artifactId>
        <version>3.11</version>
    </dependency>
    <dependency>
        <groupId>org.apache.poi</groupId>
        <artifactId>poi-ooxml</artifactId>
        <version>3.11</version>
    </dependency>
    <!-- 图片压缩功能 -->
    <!-- 缩略图 -->
    <dependency>
        <groupId>net.coobird</groupId>
        <artifactId>thumbnailator</artifactId>
        <version>0.4.6</version>
    </dependency>
    <!-- 定时调度 -->
    <dependency>
        <groupId>quartz</groupId>
        <artifactId>quartz</artifactId>
        <version>1.5.2</version>
    </dependency>
    <!-- 邮件支持 -->
    <dependency>
        <groupId>javax.mail</groupId>
        <artifactId>mail</artifactId>
        <version>1.4.1</version>
    </dependency>
</dependencies>

<build>
    <finalName>yxb</finalName>
    <plugins>
        <plugin>
            <groupId>org.apache.maven.plugins</groupId>
            <artifactId>maven-compiler-plugin</artifactId>
            <configuration>
                <source>1.8</source>
                <target>1.8</target>
            </configuration>
        </plugin>
        <plugin>
            <groupId>org.mortbay.jetty</groupId>
            <artifactId>jetty-maven-plugin</artifactId>
            <version>8.1.15.v20140411</version>
            <configuration>
                <stopPort>9966</stopPort>
                <stopKey>foo</stopKey>
                <webAppConfig>
                    <contextPath>/</contextPath>
                </webAppConfig>
            </configuration>
        </plugin>
    </plugins>
</build>


配置xml文件：

<!--开启组件扫描扫描全部的包-->
<context:component-scan base-package="cn.itsource"></context:component-scan>

<!-- 加载配置jdbc.properties-->
<context:property-placeholder location="classpath:jdbc.properties"/>
<!--配置连接池DateSource-->
<bean class="org.apache.commons.dbcp.BasicDataSource"  id="dataSource">
    <property name="driverClassName" value="${jdbc.driverClassName}"></property>
    <property name="url" value="${jdbc.url}"></property>
    <property name="username" value="${jdbc.username}"></property>
    <property name="password" value="${jdbc.password}"></property>
</bean>
<!--注入DateSource-->
<bean class="org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean" id="entityManagerFactoryBean">
    <property name="dataSource" ref="dataSource"></property>
    <!--从 domain包去连接数据库哪个包去扫描-->
    <property name="packagesToScan" value="cn.itsource.domain"></property>
    <property name="jpaVendorAdapter">
        <bean class="org.springframework.orm.jpa.vendor.HibernateJpaVendorAdapter">
            <!--是否显示sql语句-->
            <property name="showSql" value="true"></property>
            <!--是否自动创建表-->
            <property name="generateDdl" value="true"></property>
            <!--MYSQL方言-->
            <property name="databasePlatform" value="org.hibernate.dialect.MySQLDialect"></property>
        </bean>


    </property>

</bean>
<!--配置事务管理器-->
<bean class="org.springframework.orm.jpa.JpaTransactionManager" id="transactionManager">
    <property name="entityManagerFactory" ref="entityManagerFactoryBean"></property>

</bean>
<!--开启事务管理器-->
<tx:annotation-driven/>
<!-- springdatajpa配置 引入事务和实体管理工厂-->
<jpa:repositories base-package="cn.itsource.repository"
                  transaction-manager-ref="transactionManager"
                  entity-manager-factory-ref="entityManagerFactoryBean">

</jpa:repositories>

还有连接数据库的配置文件：

jdbc.driverClassName=com.mysql.jdbc.Driver
jdbc.url=jdbc:mysql:///aisell
jdbc.username=root
jdbc.password=123456

对JpaRepository接口里面的方法进行练习：

@Autowired//注入继承JpaRepository接口的子接口
private EmployeeRepository employeeRepository;

@Test//查询全部
public void testfindall()throws Exception{

    List<Employee> employees = employeeRepository.findAll();

    for (Employee employee : employees) {
        System.out.println(employee);
    }
}
@Test//查询单个
public void testone()throws Exception{

    Employee one = employeeRepository.findOne(2L);
    System.out.println(one);

}
@Test//添加
public void testadd()throws Exception{
    Employee employee = new Employee();
    employee.setUsername("打钩");
    employee.getId();
    employeeRepository.save(employee);
    /*Employee one = employeeRepository.findOne(275L);
    one.setUsername("憨够");
    employeeRepository.save(one);*/

}
@Test//删除
public void testdel()throws Exception{
    employeeRepository.delete(275L);
}

@Test //多条查询
public void testquestyall()throws Exception{

    List<Long> longs = Arrays.asList(1L, 2L, 5L, 6L);
    List<Employee> all = employeeRepository.findAll(longs);

    for (Employee employee : all) {
        System.out.println(employee);
    }

}
@Test//删除多条
public void testdelall()throws Exception{

    List<Employee> all = employeeRepository.findAll(Arrays.asList(275L,276L,277L,278L));
    employeeRepository.delete(all);
}

@Test//插叙数据总条数
public void testcont()throws Exception{

    System.out.println(employeeRepository.count());

}

JpaSpecificationExecutor的认识：

　　　　　　JpaSpecificationExecutor是JpaRepository的一个父接口可以用于动态生成Query来满足我们业务中的各种复杂场景。

对JpaSpecificationExecutor接口的一些操作练习：

@Test//排序
public void testDESC()throws Exception{
        //Sort.Direction.DESC  降序   properrtier根据什么进行排序

    Sort orders = new Sort(Sort.Direction.DESC,"id");
    List<Employee> all = employeeRepository.findAll(orders);

    for (Employee employee : all) {
        System.out.println(employee);
    }
}
@Test//分页
public void testpage()throws Exception{
    //page 表示页数   size  表示条数
    PageRequest pageRequest = new PageRequest(20, 5);
    Page<Employee> all = employeeRepository.findAll(pageRequest);

    for (Employee employee : all) {
        System.out.println(employee);

    }
}
@Test//排序加分页
public void testpagedesc()throws Exception{
    Sort orders = new Sort(Sort.Direction.DESC,"username");
    PageRequest pageRequest = new PageRequest(1, 5,orders);
    Page<Employee> all = employeeRepository.findAll(pageRequest);

    for (Employee employee : all) {
        System.out.println(employee);

    }
}


高级查询+排序+分页的练习：

//创建条件对象
EmployeeQuery employeeQuery = new EmployeeQuery();

employeeQuery.setUsername("%a%");
employeeQuery.setAge(18);

//查询条件  gt表示等于
Specification<Employee> spe = Specifications.<Employee>and().
        like(StringUtils.isNotBlank(employeeQuery.getUsername()),
                "username", "%" + employeeQuery.getUsername() + "%")
        .gt(employeeQuery.getAge() != null, "age", employeeQuery.getAge())
        .build();
//排序
Sort sort = null;
if(employeeQuery.getOrderByName()!=null){

    //获取name的属性
    String orderByName = employeeQuery.getOrderByName();
    //先定义默认的排序类型在进行判断
    Sort.Direction direction = null;

    //如果排序的类型等于ASC  那么就用升序进行排序
    if(employeeQuery.getOrderByType().equals("ASC")){
        Sort.Direction asc = Sort.Direction.ASC;

    }else{//否则进行降序
        Sort.Direction asc = Sort.Direction.DESC;
    }
    //组装排序 根据名字进行排序
    sort =new Sort(direction,orderByName);

}
//进行查询分页
//得到页数和条数
PageRequest pageRequest = new PageRequest(employeeQuery.getPageSize(), employeeQuery.getPageSize());
//
Page<Employee> all = employeeRepository1.findAll(spe, pageRequest);
for (Employee employee : all) {
    System.out.println(employee);

}

然后就是一个工具类的抽取：
把这个公共的方法提取到一个抽象类里面   然后一个类去继承该实现类复习里面的方法  最后调用

public Specification createSpecification() {
    Specification<Employee> spe = Specifications.<Employee>and().
            like(StringUtils.isNotBlank(username),
                    "username", "%" + username + "%")
            .gt(age != null, "age", age)
            .build();

    return spe;
}

Spring Data Jpa扩展：

 

@NoRepositoryBean：表示该接口不会交给Bean去管理也就不能去调用

 

接口的提取：用一个普通的接口去实现JpaRepository接口和JpaSpecificationExecutor接口 在普通的接口上面注解@NoRepositoryBean取消bean的管理权限
然后普通类定义公共的方法 想要调用该方法时就去继承该普通接口 里面就有JpaRepository接口和JpaSpecificationExecutor里面的所有方法和自己定义的方法 且
该接口上面注解的@NoRepositoryBean是取消该接口的Spring管理权限  不会去创建bean 这样更安全