SSM使用mybatis分页插件pagehepler实现分页示例

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_jb51.rar

我这里使用 maven 工程实现：

1.首先导入分页插件的依赖：

<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

<!-- 
 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：

<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：

<!-- 分页查询 -->
 <select id="finds" resulttype="country">
  select
   id,
   countryname,
   countrycode
  from
   country
 </select>

mapper 层接口：

/**
 * 查询
 * @param params
 * @return
*/
public list<country> finds();

service 业务层接口：

 /**
 * 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

/**
  * 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：

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

<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

<?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

<?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

<?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

<?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

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

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

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

<?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：

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

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
 *
 */
@service
public 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

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。