智能商贸2之查询功能

原创于 2019-07-07 14:56:10 发布 · 308 阅读

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本文介绍如何在SpringDataJpa中实现自定义Repository分页查询和高级查询功能，包括BaseRepository接口和实现类的设计，以及与EasyUI数据格式适配的方法。

Spring Data Jpa扩展

针对repository层进行抽取优化

BaseRepository接口

@NoRepositoryBean
public interface BaseRepository<T,ID extends Serializable> extends JpaRepository<T,ID>,JpaSpecificationExecutor<T>{
    //根据Query拿到分页对象(分页)
    Page findPageByQuery(BaseQuery baseQuery);
}

BaseRepositoryImpl 实现

首先添加BaseRepositoryImpl类，实现BaseRepository接口,继承SimpleJpaRepository类，使其拥有Jpa Repository的基本方法。

我们发现Repository有两个构造函数：

l SimpleJpaRepository(JpaEntityInformation entityInformation, EntityManager entityManager)

l SimpleJpaRepository(Class domainClass, EntityManager em)

这里我们实现第二个构造函数，拿到domainClass和EntityManager两个对象

public class BaseRepositoryImpl<T,ID extends Serializable> extends SimpleJpaRepository<T,ID> implements BaseRepository<T,ID> {

    private final EntityManager entityManager;

    //必需要实现父类的这个构造器
    public BaseRepositoryImpl(Class<T> domainClass, EntityManager em) {
        super(domainClass, em);
        this.entityManager = em;
    }

    @Override
    public Page findPageByQuery(BaseQuery baseQuery) {
        //第一步：拿到所有高级查询条件
        Specification spec = baseQuery.createSpecification();
        //第二步:拿到排序的值
        Sort sort = baseQuery.createSort();
        //第三步:根据条件查询分页数据并且返回
        Pageable pageable = new PageRequest(baseQuery.getJpaPage(), baseQuery.getPageSize(),sort);
        Page<T> page = super.findAll(spec, pageable);
        return page;
    }

自定义RepositoryFactoryBean

使用自定义RepositoryFactoryBean来替代默认的RepositoryFactoryBean ,使得能让spring找到自定义的类

public class BaseRepositoryFactoryBean<T extends Repository<S, ID>, S, ID extends Serializable> extends JpaRepositoryFactoryBean<T,S,ID> {

    @Override
    protected RepositoryFactorySupport createRepositoryFactory(EntityManager entityManager) {
          return new MyRepositoryFactory<T,ID>(entityManager); //注：这里创建是我们的自定义类
    }

    //继承JpaRepositoryFactory后，把返回的对象修改成我们自己的实现
    private static  class MyRepositoryFactory<T,ID extends Serializable>   extends JpaRepositoryFactory{
        private final EntityManager entityManager;
        /**
         * Creates a new {@link JpaRepositoryFactory}.
         *
         * @param entityManager must not be {@literal null}
         */
        public MyRepositoryFactory(EntityManager entityManager) {
            super(entityManager);
            this.entityManager = entityManager;
        }
	   //这里返回最后的功能对象
        @Override
        protected Object getTargetRepository(RepositoryInformation information) {
            return new BaseRepositoryImpl<T,ID>((Class<T>)information.getDomainType(),entityManager);
        }
	   //确定功能对象的类型
        @Override
        protected Class<?> getRepositoryBaseClass(RepositoryMetadata metadata) {
            return BaseRepositoryImpl.class;
        }
    }
}

xml配置

<jpa:repositories base-package="cn.itsource.pss.repository"
   transaction-manager-ref="transactionManager"
   entity-manager-factory-ref="entityManagerFactory"
   factory-class="cn.itsource.pss.repository.BaseRepositoryFactoryBean"
/>

查询功能

Service层

抽取父接口 IBaseService
子接口IEmployeeService 继承 IBaseService并指定泛型
添加BaseServiceImpl 实现 IBaseService
添加EmployeeServiceImpl继承 IBaseService, 实现IEmployeeService

注意:泛型使用规范;

注入 BaseRepository对象时,添加泛型
```
@Autowired
private BaseRepository<T,ID> baseRepository;
```

配置spring-mvc

1.导包

<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>

2.配置applicationContext-mvc.xml

<?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:mvc="http://www.springframework.org/schema/mvc"
       xsi:schemaLocation="
         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.xsd
         http://www.springframework.org/schema/mvc
         http://www.springframework.org/schema/mvc/spring-mvc.xsd
    ">
    <!-- 对静态资源进行放行 -->
    <mvc:default-servlet-handler />
    <!-- 扫描controller部分的包 -->
    <!-- @Component组件, @Repository持久层, @Service业务逻辑层, and @Controller控制器 -->
    <context:component-scan base-package="cn.itsource.pss.web" />
    <!-- 添加mvc对@RequestMapping等注解的支持 -->
    <mvc:annotation-driven />

    <!-- ViewResolver 视图解析器 (struts2视图类型类似) -->
    <bean class="org.springframework.web.servlet.view.InternalResourceViewResolver">
        <!-- 设置视图路径的前后缀，该配置可以让我们写视图路径的时候更简单。 -->
        <!-- 希望跳转jsp是[/WEB-INF/views/前缀][xxx变量][.jsp后缀] -->
        <!-- * @see #setPrefix -->
        <property name="prefix" value="/WEB-INF/views/" />
        <!-- * @see #setSuffix -->
        <property name="suffix" value=".jsp" />
    </bean>

    <!-- 错误：提示告诉开发者你没有配置文件上传解析器。 -->
    <bean id="multipartResolver" class="org.springframework.web.multipart.commons.CommonsMultipartResolver">
        <!-- 设置上传文件的最大尺寸为1MB -->
        <property name="maxUploadSize">
            <value>1048576</value>
        </property>
    </bean>
</beans>

3.配置web.xml

<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://xmlns.jcp.org/xml/ns/javaee"
         xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/javaee http://xmlns.jcp.org/xml/ns/javaee/web-app_3_1.xsd"
         id="WebApp_ID" version="3.1">

    <!-- 读取SpringMVC -->
    <context-param>
        <param-name>contextConfigLocation</param-name>
        <param-value>classpath:applicationContext.xml</param-value>
    </context-param>
    <!-- 启动Spring的监听器 -->
    <listener>
        <listener-class>org.springframework.web.context.ContextLoaderListener</listener-class>
    </listener>

    <!--  配置解决中文乱码的问题 -->
    <filter>
        <filter-name>characterEncodingFilter</filter-name>
        <filter-class>org.springframework.web.filter.CharacterEncodingFilter</filter-class>
        <init-param>
            <param-name>encoding</param-name>
            <param-value>UTF-8</param-value>
        </init-param>
        <init-param>
            <param-name>forceEncoding</param-name>
            <param-value>true</param-value>
        </init-param>
    </filter>
    <filter-mapping>
        <filter-name>characterEncodingFilter</filter-name>
        <url-pattern>/*</url-pattern>
    </filter-mapping>

    <!-- 配置核心控制器-->
    <servlet>
        <servlet-name>dispatcher</servlet-name>
        <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
        <init-param>
            <!-- 告诉SpringMVC到哪里去找配置文件 -->
            <param-name>contextConfigLocation</param-name>
            <!-- 注意:这里只读取springmvc的xml -->
            <param-value>classpath:applicationContext-mvc.xml</param-value>
        </init-param>
        <!-- Servlet默认在每一次访问的时候创建 -->
        <load-on-startup>1</load-on-startup>
    </servlet>
    <servlet-mapping>
        <servlet-name>dispatcher</servlet-name>
        <url-pattern>/</url-pattern>
    </servlet-mapping>
</web-app>

Controller层

父类抽取
@Controller注解

主页面

1.拷贝easyui文件夹到webapp根目录下

2.主页面跳转的controller

3.main.jsp

注意: 抽取head.jsp专门用来导入需要使用的easyui及其余共享的引入文件

员工查询页面

employee.jsp,用来展示数据

准备一个UIpage.java,解决SpringDataJpa返回的数据和EasyUI中的数据匹配不上的问题

public class UiPage {
    private long total; //总条数
    private List rows; //每页数据
    public UiPage(){}
    public UiPage(Page page){
        total = page.getTotalElements();
        rows = page.getContent();
    }
}

修改BaseQuery 中的参数对应

public abstract class BaseQuery {
 ….
    //兼容Easyui的分页
    public void setPage(int page) {
        this.currentPage = page;
    }
    public void setRows(int rows) {
        this.pageSize = rows;
    }
}

controller层的方法(返回一个包装过的类)

//查询分页数据
    @RequestMapping("/page")
    @ResponseBody
    public UiPage page(EmployeeQuery query){
        return new UiPage(employeeService.findPageByQuery(query));
    }

完善Employee对象

建立employee与department之间的关联(many2one)

配置web.xml解决noSession问题

<!-- 加上OpenEntityManager -->
<filter>
    <filter-name>openEntity</filter-name>
    <filter-class>org.springframework.orm.jpa.support.OpenEntityManagerInViewFilter</filter-class>
</filter>
<filter-mapping>
    <filter-name>openEntity</filter-name>
    <url-pattern>/*</url-pattern>
</filter-mapping>

解决department对象设置的懒加载引起的"No serializer found for class"问题

创建新类

public class CustomMapper extends ObjectMapper {
    public CustomMapper() {
        this.setSerializationInclusion(JsonInclude.Include.NON_NULL);
        // 设置 SerializationFeature.FAIL_ON_EMPTY_BEANS 为 false
        this.configure(SerializationFeature.FAIL_ON_EMPTY_BEANS, false);
    }
}

配置applicationContext-mvc.xml

<!-- Spring MVC 配置 -->
<mvc:annotation-driven>
    <mvc:message-converters>
        <bean class="org.springframework.http.converter.json.MappingJackson2HttpMessageConverter">
            <property name="supportedMediaTypes">
                <list>
                    <value>application/json; charset=UTF-8</value>
                    <value>application/x-www-form-urlencoded; charset=UTF-8</value>
                </list>
            </property>
            <!-- No serializer:配置 objectMapper 为我们自定义扩展后的 CustomMapper,解决了返回对象有关系对象的报错问题 -->
            <property name="objectMapper">
                <bean class="cn.itsource.pss.common.CustomMapper"></bean>
            </property>
        </bean>
    </mvc:message-converters>
</mvc:annotation-driven>

高级查询

employee.jsp页面
employee.js书写
页面查询部门信息时,需要在下拉框展示,因此单独用UtilController来查询
检查EmployeeQuery是否有模糊查询及部门的准确查询

功能拓展

排序功能

easyui返回的排序名称和类型为 sort和order ,需要更改一下 BaseQuery 中set方法中形式参数名称

employee.jsp中需要设置 sortable=“true”

<th width="20"  field="username" sortable="true">用户名</th>

隐藏字段

通过easyui扩展库查询到该方法

导入依赖的css和js文件(可在demo的f12中进行查看拷贝)

<link href="/easyui/plugin/datagrid/jeasyui.extensions.datagrid.css" rel="stylesheet" />
<script src="/easyui/plugin/menu/jeasyui.extensions.menu.js"></script>
<script src="/easyui/plugin/datagrid/jeasyui.extensions.datagrid.getColumnInfo.js"></script>
<script src="/easyui/plugin/datagrid/jeasyui.extensions.datagrid.columnToggle.js"></script>

给datagird配置enableHeaderClickMenu=“true”

<table id="employeeGrid" class="easyui-datagrid" data-options="fit:true,fixed:true,fitColumns:true,toolbar:'#tb',singleSelect:true"
       url="/employee/page"
       iconCls="icon-save"
       enableHeaderClickMenu="true"
       rownumbers="true" pagination="true">