前几天在这里分享了手写 sql 分页查询实现分页，现在来看看使用 mybatis 分页插件 pagehepler 来实现分页
使用分页插件的原因，简化了sql代码的写法，实现较好的物理分页，比写一段完整的分页sql代码，也能减少了误差性。
Mybatis分页插件 demo 项目地址：free-Mybatis_PageHelper
我这里使用 maven 工程实现：
1.首先导入分页插件的依赖：
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<dependency> <groupId>com.github.pagehelper</groupId> <artifactId>pagehelper</artifactId> <version>5.0.0</version> </dependency> |
2.配置分页拦截器插件
官方文档有两种配置分页拦截器插件
1. 在 MyBatis 配置 xml 中配置拦截器插件
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<!-- plugins在配置文件中的位置必须符合要求，否则会报错，顺序如下: properties?, settings?, typeAliases?, typeHandlers?, objectFactory?,objectWrapperFactory?, plugins?, environments?, databaseIdProvider?, mappers?--><plugins> <!-- com.github.pagehelper为PageHelper类所在包名 --> <plugin interceptor="com.github.pagehelper.PageInterceptor"> <!-- 使用下面的方式配置参数，后面会有所有的参数介绍 --> <property name="param1" value="value1"/> </plugin></plugins> |
2. 在 Spring 配置文件中配置拦截器插件
使用 spring 的属性配置方式，可以使用 plugins 属性像下面这样配置：
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<bean id="sqlSessionFactory" class="org.mybatis.spring.SqlSessionFactoryBean"> <!-- 注意其他配置 --> <property name="plugins"> <array> <bean class="com.github.pagehelper.PageInterceptor"> <property name="properties"> <!--使用下面的方式配置参数，一行配置一个 --> <value> params=value1 </value> </property> </bean> </array> </property></bean> |
这里我项目中使用的是第二种，里面的参数根据实际情况配置，也可以不配置
3.调用方法
mapper 层 sql 语句按照一般查询写法，不用写分页：
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<!-- 分页查询 --> <select id="finds" resultType="country"> SELECT id, countryname, countrycode FROM country </select> |
mapper 层接口：
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/** * 查询 * @param params * @return*/public List<Country> finds(); |
service 业务层接口：
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/*** 分页查询* @param params 分页参数 pageNo（页码），pageSize（每页查询数目）* @return*/public PageInfo<Country> finds(Params params); |
service 业务层实现类：PageHelper.startPage(1, 10);第一个参数表示第几页，第二个参数表示每页显示的记录数
执行完 PageHelper.startPage(1, 10);语句后，紧跟着的第一个select方法会被分页：List<Country> blogs = countryMapper.finds();
然后再用 PageInfo 对查询结果进行包装，PageInfo<Country> pageInfo = new PageInfo<Country>(blogs);
并将 pageInfo 返回到控制层
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/** * 查询 */ public PageInfo<Country> finds(Params params) //查询 int pageNo = params.getPageNo(); int pageSize = params.getPageSize(); PageHelper.startPage(pageNo, pageSize); List<Country> blogs = countryMapper.finds(); //用PageInfo对结果进行包装 PageInfo<Country> pageInfo = new PageInfo<Country>(blogs); return pageInfo; } |
这里返回 pageInfo 后，在 controller 层传入 params 分页参数 和 解析 pageInfo：
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List<Country> clist = pageInfo.getList(); 再将 clist 放进作用域，在前台页面利用<c:forEach></c:forEach>可循环获得分页数据/** * 首页，并且分页查询 * @return */ @RequestMapping("/index") public ModelAndView index(Params params){ ModelAndView modelAndView = new ModelAndView(); //一开始第一页，查询10条 params.setPageNo(1); params.setPageSize(10); PageInfo<Country> pageInfo = countryService.finds(params); List<Country> clist = pageInfo.getList(); //查询数量 long couts = countryService.counts(); modelAndView.addObject("clist", clist); modelAndView.addObject("couts", couts); modelAndView.setViewName("index"); return modelAndView; } |
上面说的都是关键分页的实现代码，现在看看全部配置和实现的代码：
pom.xml
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<project xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://maven.apache.org/POM/4.0.0" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/maven-v4_0_0.xsd"> <modelVersion>4.0.0</modelVersion> <groupId>com.krry</groupId> <artifactId>maven_pagehepler_ora</artifactId> <packaging>war</packaging> <version>1.0-SNAPSHOT</version> <name>maven_pagehepler_ora</name> <url>http://maven.apache.org</url> <properties> <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding> <!-- MyBatis Generator --> <!-- Java接口和实体类 --> <targetJavaProject>${basedir}/src/main/java</targetJavaProject> <targetMapperPackage>com.isea533.mybatis.mapper</targetMapperPackage> <targetModelPackage>com.isea533.mybatis.model</targetModelPackage> <!-- XML生成路径 --> <targetResourcesProject>${basedir}/src/main/resources</targetResourcesProject> <targetXMLPackage>mapper</targetXMLPackage> <!-- 编译jdk版本 --> <jdk.version>1.6</jdk.version> <!-- 依赖版本 --> <mybatis.version>3.3.1</mybatis.version> <mapper.version>3.3.6</mapper.version> <pagehelper.version>5.0.0</pagehelper.version> <mysql.version>5.1.29</mysql.version> <spring.version>4.1.2.RELEASE</spring.version> <mybatis.spring.version>1.2.4</mybatis.spring.version> </properties> <dependencies> <dependency> <groupId>junit</groupId> <artifactId>junit</artifactId> <version>4.11</version> <scope>test</scope> </dependency> <dependency> <groupId>log4j</groupId> <artifactId>log4j</artifactId> <version>1.2.17</version> </dependency> <!--web--> <dependency> <groupId>javax.servlet</groupId> <artifactId>servlet-api</artifactId> <version>2.5</version> <scope>provided</scope> </dependency> <dependency> <groupId>javax.servlet.jsp</groupId> <artifactId>jsp-api</artifactId> <version>2.1</version> <scope>provided</scope> </dependency> <dependency> <groupId>javax.servlet</groupId> <artifactId>jstl</artifactId> <version>1.2</version> </dependency> <dependency> <groupId>javax.ws.rs</groupId> <artifactId>javax.ws.rs-api</artifactId> <version>2.0</version> </dependency> <dependency> <groupId>javax.websocket</groupId> <artifactId>javax.websocket-api</artifactId> <version>1.0</version> </dependency> <dependency> <groupId>javax.annotation</groupId> <artifactId>javax.annotation-api</artifactId> <version>1.2</version> </dependency> <dependency> <groupId>javax.transaction</groupId> <artifactId>javax.transaction-api</artifactId> <version>1.2</version> </dependency> <!--Spring--> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-context</artifactId> </dependency> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-orm</artifactId> </dependency> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-oxm</artifactId> </dependency> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-jdbc</artifactId> </dependency> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-tx</artifactId> </dependency> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-web</artifactId> </dependency> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-webmvc</artifactId> </dependency> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-aop</artifactId> </dependency> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-test</artifactId> </dependency> <!--spring-oxm依赖--> <dependency> <groupId>org.codehaus.castor</groupId> <artifactId>castor-xml</artifactId> <version>1.3.3</version> </dependency> <!--spring-json依赖--> <dependency> <groupId>com.fasterxml.jackson.core</groupId> <artifactId>jackson-databind</artifactId> <version>2.4.2</version> </dependency> <dependency> <groupId>com.fasterxml.jackson.dataformat</groupId> <artifactId>jackson-dataformat-xml</artifactId> <version>2.4.2</version> </dependency> <!--spring-aop依赖--> <dependency> <groupId>org.aspectj</groupId> <artifactId>aspectjweaver</artifactId> <version>1.8.2</version> </dependency> <!--上传文件--> <dependency> <groupId>commons-fileupload</groupId> <artifactId>commons-fileupload</artifactId> <version>1.3.1</version> </dependency> <!--mysql--> <dependency> <groupId>mysql</groupId> <artifactId>mysql-connector-java</artifactId> <version>${mysql.version}</version> </dependency> <!--druid--> <dependency> <groupId>com.alibaba</groupId> <artifactId>druid</artifactId> <version>1.0.11</version> </dependency> <!--Mybatis--> <dependency> <groupId>org.mybatis</groupId> <artifactId>mybatis</artifactId> <version>${mybatis.version}</version> </dependency> <dependency> <groupId>org.mybatis</groupId> <artifactId>mybatis-spring</artifactId> <version>${mybatis.spring.version}</version> </dependency> <!-- Mybatis Generator --> <dependency> <groupId>org.mybatis.generator</groupId> <artifactId>mybatis-generator-core</artifactId> <version>1.3.2</version> <scope>compile</scope> <optional>true</optional> </dependency> <!--分页插件--> <dependency> <groupId>com.github.pagehelper</groupId> <artifactId>pagehelper</artifactId> <version>${pagehelper.version}</version> </dependency> <!--通用Mapper--> <dependency> <groupId>tk.mybatis</groupId> <artifactId>mapper</artifactId> <version>${mapper.version}</version> </dependency> <dependency> <groupId>org.apache.commons</groupId> <artifactId>commons-lang3</artifactId> <version>3.3.2</version> </dependency> </dependencies> <dependencyManagement> <dependencies> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-framework-bom</artifactId> <version>${spring.version}</version> <type>pom</type> <scope>import</scope> </dependency> </dependencies> </dependencyManagement> <repositories> <repository> <id>nexus</id> <name>local private nexus</name> <url>http://maven.oschina.net/content/groups/public/</url> <releases> <enabled>true</enabled> </releases> <snapshots> <enabled>false</enabled> </snapshots> </repository> <repository> <id>sonatype-nexus-releases</id> <name>Sonatype Nexus Releases</name> <url>http://oss.sonatype.org/content/repositories/releases</url> <releases> <enabled>true</enabled> </releases> <snapshots> <enabled>false</enabled> </snapshots> </repository> <repository> <id>sonatype-nexus-snapshots</id> <name>Sonatype Nexus Snapshots</name> <url>http://oss.sonatype.org/content/repositories/snapshots</url> <releases> <enabled>false</enabled> </releases> <snapshots> <enabled>true</enabled> </snapshots> </repository> </repositories> <build> <plugins> <plugin> <groupId>org.apache.maven.plugins</groupId> <artifactId>maven-compiler-plugin</artifactId> <version>3.2</version> <configuration> <source>1.7</source> <target>1.7</target> </configuration> </plugin> </plugins> </build></project> |
applicationContext.xml
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<?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:aop="http://www.springframework.org/schema/aop" xmlns:context="http://www.springframework.org/schema/context" xmlns:tx="http://www.springframework.org/schema/tx" xmlns:util="http://www.springframework.org/schema/util" xmlns:p="http://www.springframework.org/schema/p" xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop-3.0.xsd http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx-3.0.xsd http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-3.0.xsd http://www.springframework.org/schema/util http://www.springframework.org/schema/util/spring-util-3.0.xsd "> <!-- 配置包扫描 --> <context:component-scan base-package="com.krry"></context:component-scan> <!-- 导入外部资源文件 --> <context:property-placeholder location="classpath:jdbc.properties" /> <!-- 配置druid数据源 --> <bean id="dataSource" class="com.alibaba.druid.pool.DruidDataSource" init-method="init" destroy-method="close"> <property name="driverClassName" value="${db.driver}" /> <property name="url" value="${db.url}" /> <property name="username" value="${db.username}" /> <property name="password" value="${db.password}" /> </bean> <!-- 注册事务管理器 --> <bean id="txMgr" class="org.springframework.jdbc.datasource.DataSourceTransactionManager"> <property name="dataSource" ref="dataSource"></property> </bean> <!-- 开启事务注解驱动 --> <tx:annotation-driven transaction-manager="txMgr" /> <!-- 配置mybatis的sqlSessionFactory --> <bean id="sqlSessionFactory" class="org.mybatis.spring.SqlSessionFactoryBean"> <property name="dataSource" ref="dataSource"/> <property name="configLocation" value="classpath:mybatis-config.xml"></property> <property name="typeAliasesPackage" value="com.krry.entity"/> <property name="plugins"> <array> <bean class="com.github.pagehelper.PageInterceptor"> <!-- 这里的几个配置主要演示如何使用，如果不理解，一定要去掉下面的配置 --> <property name="properties"> <value> </value> </property> </bean> </array> </property> </bean> <!-- 配置可以整体扫描Mapper的一个扫描器 --> <bean class="org.mybatis.spring.mapper.MapperScannerConfigurer"> <!--如果有多个报路径,用逗号分开即可 --> <property name="basePackage" value="com.krry.mapper"></property> <property name="sqlSessionFactoryBeanName" value="sqlSessionFactory"></property> </bean> </beans> |
mybatis-config.xml
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<?xml version="1.0" encoding="UTF-8"?> <!DOCTYPE configuration PUBLIC "-//mybatis.org//DTD Config 3.0//EN" "http://mybatis.org/dtd/mybatis-3-config.dtd"> <configuration> <settings> <!-- 全局映射器启用缓存 --> <setting name="cacheEnabled" value="true" /> <!-- 查询时，关闭关联对象即时加载以提高性能 --> <setting name="lazyLoadingEnabled" value="true" /> <!-- 设置关联对象加载的形态，此处为按需加载字段(加载字段由SQL指 定)，不会加载关联表的所有字段，以提高性能 --> <setting name="aggressiveLazyLoading" value="false" /> <!-- 对于未知的SQL查询，允许返回不同的结果集以达到通用的效果 --> <setting name="multipleResultSetsEnabled" value="true" /> <!-- 允许使用列标签代替列名 --> <setting name="useColumnLabel" value="true" /> <!-- 允许使用自定义的主键值(比如由程序生成的UUID 32位编码作为键值)，数据表的PK生成策略将被覆盖 --> <setting name="useGeneratedKeys" value="true" /> <!-- 给予被嵌套的resultMap以字段-属性的映射支持 --> <setting name="autoMappingBehavior" value="FULL" /> <!-- 对于批量更新操作缓存SQL以提高性能 --> <setting name="defaultExecutorType" value="BATCH" /> <!-- 数据库超过25000秒仍未响应则超时 --> <setting name="defaultStatementTimeout" value="25" /> <setting name="lazyLoadTriggerMethods" value="equals,clone,hashCode,toString"/> </settings> <typeAliases> <!--自定义user对象的别名 --> <!-- <typeAlias type="com.krry.mybatis.sysmanage.entity.User" alias="user"/> --> <!-- 批量定义别名 --> <package name="com.krry.entity" /> </typeAliases> </configuration> |
springmvc.xml
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<?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:p="http://www.springframework.org/schema/p" xmlns:context="http://www.springframework.org/schema/context" xmlns:util="http://www.springframework.org/schema/util" xmlns:mvc="http://www.springframework.org/schema/mvc" xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-3.0.xsd http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-3.0.xsd http://www.springframework.org/schema/util http://www.springframework.org/schema/util/spring-util-3.0.xsd http://www.springframework.org/schema/mvc http://www.springframework.org/schema/mvc/spring-mvc.xsd "> <!-- 开启注解模式驱动 --> <bean class="org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerAdapter" /> <!-- 开启mvc的注解模式 user 还会注册一个ConversionService 子类FormattingConversionServiceFactoryBean--> <mvc:annotation-driven> <mvc:message-converters register-defaults="true"> <bean class="com.krry.core.UTF8StringHttpMessageConverter"> <property name="supportedMediaTypes"> <list> <value>text/plain;charset=UTF-8</value> <value>text/html;charset=UTF-8</value> </list> </property> </bean> <bean class="org.springframework.http.converter.BufferedImageHttpMessageConverter"/> <bean class="org.springframework.http.converter.ByteArrayHttpMessageConverter"/> <bean class="org.springframework.http.converter.json.MappingJackson2HttpMessageConverter"> <property name="prefixJson" value="false" /> <property name="objectMapper"> <bean class="com.fasterxml.jackson.databind.ObjectMapper"> <!-- 处理responseBody 里面日期类型 --> <property name="dateFormat"> <bean class="java.text.SimpleDateFormat"> <constructor-arg type="java.lang.String" value="yyyy-MM-dd HH:mm:ss" /> </bean> </property> <!-- 为null字段时不显示 --> <property name="serializationInclusion"> <value type="com.fasterxml.jackson.annotation.JsonInclude.Include">NON_NULL</value> </property> </bean> </property> <property name="supportedMediaTypes"> <list> <value>application/json;charset=UTF-8</value> <value>application/x-www-form-urlencoded;charset=UTF-8</value> </list> </property> </bean> </mvc:message-converters> </mvc:annotation-driven> <!-- 扫包 --> <context:component-scan base-package="com.krry.controller"></context:component-scan> <!--对静态资源文件的访问 必须要设置，因为在springmvc的配置中配置了/匹配所有请求， 此工程所有的请求(.do ,addUser,js/image/css)都会被springmvc解析, 必须对所有的静态资源文件进行过滤放行 --> <!-- 静态资源过滤 下面二选一--> <!--<mvc:default-servlet-handler/> --> <mvc:resources mapping="/resource/**" location="/resource/" /> <!-- 视图渲染 jsp/freemaker/velocity--> <bean class="org.springframework.web.servlet.view.InternalResourceViewResolver"> <!-- 制定页面存放的路径 --> <property name="prefix" value="/WEB-INF/pages/"></property> <!-- 文件的后缀 --> <property name="suffix" value=".jsp"></property> </bean> </beans> |
jdbc.properties 和 log4j.properties 就不用展示了，都差不多的
web.xml
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<?xml version="1.0" encoding="UTF-8"?><web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://java.sun.com/xml/ns/javaee" xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd" version="2.5"> <display-name>maven_pagehepler</display-name> <welcome-file-list> <welcome-file>index/index</welcome-file> </welcome-file-list> <context-param> <param-name>contextConfigLocation</param-name> <param-value>classpath:applicationContext.xml</param-value> </context-param> <listener> <listener-class>org.springframework.web.context.ContextLoaderListener</listener-class> </listener> <listener> <listener-class>org.springframework.web.util.IntrospectorCleanupListener</listener-class> </listener> <filter> <filter-name>encoding</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> </filter> <filter-mapping> <filter-name>encoding</filter-name> <url-pattern>/*</url-pattern> </filter-mapping> <servlet> <servlet-name>maven_pagehepler</servlet-name> <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class> <init-param> <param-name>contextConfigLocation</param-name> <param-value>classpath:springmvc.xml</param-value> </init-param> </servlet> <servlet-mapping> <servlet-name>maven_pagehepler</servlet-name> <url-pattern>/index/index</url-pattern> </servlet-mapping> <servlet-mapping> <servlet-name>maven_pagehepler</servlet-name> <url-pattern>/</url-pattern> </servlet-mapping></web-app> |
实体类：Country.java
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package com.krry.entity;public class Country { /** * 主键 */ private Integer id; /** * 名称 */ private String countryname; /** * 代码 */ private String countrycode; public Country(Integer id, String countryname, String countrycode) { this.id = id; this.countryname = countryname; this.countrycode = countrycode; } /** * 获取主键 * * @return Id - 主键 */ public Integer getId() { return id; } /** * 设置主键 * * @param id 主键 */ public void setId(Integer id) { this.id = id; } /** * 获取名称 * * @return countryname - 名称 */ public String getCountryname() { return countryname; } /** * 设置名称 * * @param countryname 名称 */ public void setCountryname(String countryname) { this.countryname = countryname; } /** * 获取代码 * * @return countrycode - 代码 */ public String getCountrycode() { return countrycode; } /** * 设置代码 * * @param countrycode 代码 */ public void setCountrycode(String countrycode) { this.countrycode = countrycode; }} |
Params.java
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package com.krry.entity;/** * * Params * @author krry * @version 1.0.0 * */public class Params { private Integer pageSize = 10; private Integer pageNo = 0; public Integer getPageNo() { return pageNo; } public void setPageNo(Integer pageNo) { this.pageNo = pageNo; } public Integer getPageSize() { return pageSize; } public void setPageSize(Integer pageSize) { this.pageSize = pageSize; }} |
持久层：CountryMapper.java
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package com.krry.mapper;import java.util.List;import com.krry.entity.Country;/** * * Mapper：操作数据库 * @author krry * @version 1.0.0 * */public interface CountryMapper { /** * 查询 * @param params * @return */ public List<Country> finds(); /** * 计算 * com.krry.dao.admin * 方法名：countBlogs * @author krry * @param params * @return int * @exception * @since 1.0.0 */ public long counts(); } |
CountryMapper.xml
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<?xml version="1.0" encoding="UTF-8" ?><!DOCTYPE mapper PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN""http://mybatis.org/dtd/mybatis-3-mapper.dtd"><mapper namespace="com.krry.mapper.CountryMapper" > <!-- 分页查询 --> <select id="finds" resultType="country"> SELECT id, countryname, countrycode FROM country </select> <!-- 查询博客数量 --> <select id="counts" resultType="long"> SELECT count(*) FROM country </select> </mapper> |
业务层接口：
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package com.krry.service;import java.util.HashMap;import java.util.List;import javax.servlet.http.HttpServletRequest;import org.apache.ibatis.annotations.Param;import com.github.pagehelper.PageInfo;import com.krry.entity.Country;import com.krry.entity.Params;/** * service层：处理业务逻辑（impl里面实现） * @author asusaad * */public interface ICountryService { /** * 分页查询所有博客 * @param params 分页参数 pageNo（页码），pageSize（每页查询数目） * @return */ public PageInfo<Country> finds(Params params); /** * 计算博客数量 * @param params * @return */ public long counts(); } |
业务层实现类
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package com.krry.service.impl;import java.util.HashMap;import java.util.List;import org.springframework.beans.factory.annotation.Autowired;import org.springframework.stereotype.Service;import org.springframework.web.servlet.ModelAndView;import com.github.pagehelper.PageHelper;import com.github.pagehelper.PageInfo;import com.krry.entity.Country;import com.krry.entity.Params;import com.krry.mapper.CountryMapper;import com.krry.service.ICountryService;/** * 实现service层接口 * @author asusaad * */@Servicepublic class CountryService implements ICountryService{ @Autowired private CountryMapper countryMapper; /** * 查询 */ public PageInfo<Country> finds(Params params) { //查询 int pageNo = params.getPageNo(); int pageSize = params.getPageSize(); PageHelper.startPage(pageNo, pageSize); List<Country> blogs = countryMapper.finds(); //用PageInfo对结果进行包装 PageInfo<Country> pageInfo = new PageInfo<Country>(blogs); return pageInfo; } /** * 计算 * @param params * @return */ public long counts(){ long couts = countryMapper.counts(); return couts; }} |
控制层：KrryController.java
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package com.krry.controller;import java.util.ArrayList;import java.util.HashMap;import java.util.List;import org.junit.Test;import org.springframework.beans.factory.annotation.Autowired;import org.springframework.stereotype.Controller;import org.springframework.web.bind.annotation.RequestMapping;import org.springframework.web.bind.annotation.ResponseBody;import org.springframework.web.servlet.ModelAndView;import com.github.pagehelper.PageInfo;import com.krry.entity.Country;import com.krry.entity.Params;import com.krry.service.ICountryService;/** * KrryController * controller层，作为请求转发 * @author asusaad * */@Controller //表示是多例模式，每个用户返回的web层是不一样的@RequestMapping("/index")public class KrryController { @Autowired private ICountryService countryService; /** * 首页，并且分页查询 * @return */ @RequestMapping("/index") public ModelAndView index(Params params){ ModelAndView modelAndView = new ModelAndView(); //一开始第一页，查询10条 params.setPageNo(1); params.setPageSize(10); PageInfo<Country> pageInfo = countryService.finds(params); List<Country> clist = pageInfo.getList(); //查询数量 long couts = countryService.counts(); modelAndView.addObject("clist", clist); modelAndView.addObject("couts", couts); modelAndView.setViewName("index"); return modelAndView; } /** * ajax请求 的 分页查询 * @param params * @return */ @ResponseBody @RequestMapping("/loadData") public HashMap<String, Object> loadData(Params params){ HashMap<String, Object> map = new HashMap<String, Object>(); PageInfo<Country> pageInfo = countryService.finds(params); List<Country> clist = pageInfo.getList(); map.put("clist", clist); return map; }// } |
以上就是本文的全部内容，希望对大家的学习有所帮助，也希望大家多多支持服务器之家。
原文链接：http://www.cnblogs.com/ainyi/p/8625672.html
