SSM使用mybatis分頁插件pagehepler實(shí)現(xiàn)分頁示例
更新時(shí)間：2018年03月23日 10:06:07 作者：筱月
本篇文章主要介紹了SSM使用mybatis分頁插件pagehepler實(shí)現(xiàn)分頁示例，使用分頁插件的原因，簡(jiǎn)化了sql代碼的寫法，實(shí)現(xiàn)較好的物理分頁，非常具有實(shí)用價(jià)值，需要的朋友可以參考下
前幾天在這里分享了手寫 sql 分頁查詢實(shí)現(xiàn)分頁，現(xiàn)在來看看使用 mybatis 分頁插件 pagehepler 來實(shí)現(xiàn)分頁
使用分頁插件的原因，簡(jiǎn)化了sql代碼的寫法，實(shí)現(xiàn)較好的物理分頁，比寫一段完整的分頁sql代碼，也能減少了誤差性。
Mybatis分頁插件 demo 項(xiàng)目地址：free-Mybatis_PageHelper_jb51.rar
我這里使用 maven 工程實(shí)現(xiàn)：
1.首先導(dǎo)入分頁插件的依賴：
<dependency> <groupId>com.github.pagehelper</groupId> <artifactId>pagehelper</artifactId> <version>5.0.0</version> </dependency>
2.配置分頁攔截器插件
官方文檔有兩種配置分頁攔截器插件
1. 在 MyBatis 配置 xml 中配置攔截器插件
<!-- plugins在配置文件中的位置必須符合要求，否則會(huì)報(bào)錯(cuò)，順序如下: properties?, settings?, typeAliases?, typeHandlers?, objectFactory?,objectWrapperFactory?, plugins?, environments?, databaseIdProvider?, mappers? --> <plugins> <!-- com.github.pagehelper為PageHelper類所在包名 --> <plugin interceptor="com.github.pagehelper.PageInterceptor"> <!-- 使用下面的方式配置參數(shù)，后面會(huì)有所有的參數(shù)介紹 --> <property name="param1" value="value1"/> </plugin> </plugins>
2. 在 Spring 配置文件中配置攔截器插件
使用 spring 的屬性配置方式，可以使用 plugins 屬性像下面這樣配置：
<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參數(shù)，一行配置一個(gè) --> <value> params=value1 </value> </property> </bean> </array> </property> </bean>
這里我項(xiàng)目中使用的是第二種，里面的參數(shù)根據(jù)實(shí)際情況配置，也可以不配置
3.調(diào)用方法
mapper 層 sql 語句按照一般查詢寫法，不用寫分頁：
<!-- 分頁查詢 --> <select id="finds" resultType="country"> SELECT id, countryname, countrycode FROM country </select>
mapper 層接口：
/** * 查詢 * @param params * @return */ public List<Country> finds();
service 業(yè)務(wù)層接口：
/** * 分頁查詢 * @param params 分頁參數(shù) pageNo（頁碼），pageSize（每頁查詢數(shù)目） * @return */ public PageInfo<Country> finds(Params params);
service 業(yè)務(wù)層實(shí)現(xiàn)類：PageHelper.startPage(1, 10);第一個(gè)參數(shù)表示第幾頁，第二個(gè)參數(shù)表示每頁顯示的記錄數(shù)
執(zhí)行完 PageHelper.startPage(1, 10);語句后，緊跟著的第一個(gè)select方法會(huì)被分頁：List<Country> blogs = countryMapper.finds();
然后再用 PageInfo 對(duì)查詢結(jié)果進(jìn)行包裝，PageInfo<Country> pageInfo = new PageInfo<Country>(blogs);
并將 pageInfo 返回到控制層
/** * 查詢 */ public PageInfo<Country> finds(Params params) //查詢 int pageNo = params.getPageNo(); int pageSize = params.getPageSize(); PageHelper.startPage(pageNo, pageSize); List<Country> blogs = countryMapper.finds(); //用PageInfo對(duì)結(jié)果進(jìn)行包裝 PageInfo<Country> pageInfo = new PageInfo<Country>(blogs); return pageInfo; }
這里返回 pageInfo 后，在 controller 層傳入 params 分頁參數(shù) 和 解析 pageInfo：
List<Country> clist = pageInfo.getList(); 再將 clist 放進(jìn)作用域，在前臺(tái)頁面利用<c:forEach></c:forEach>可循環(huán)獲得分頁數(shù)據(jù)
/**
* 首頁，并且分頁查詢
* @return
*/
@RequestMapping("/index")
public ModelAndView index(Params params){ ModelAndView modelAndView = new ModelAndView();
//一開始第一頁，查詢10條
params.setPageNo(1);
params.setPageSize(10);
PageInfo<Country> pageInfo = countryService.finds(params);
List<Country> clist = pageInfo.getList();
//查詢數(shù)量
long couts = countryService.counts();
modelAndView.addObject("clist", clist);
modelAndView.addObject("couts", couts);
modelAndView.setViewName("index");
return modelAndView;
}
上面說的都是關(guān)鍵分頁的實(shí)現(xiàn)代碼，現(xiàn)在看看全部配置和實(shí)現(xiàn)的代碼：
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接口和實(shí)體類 -->
<targetJavaProject>${basedir}/src/main/java</targetJavaProject>
<targetMapperPackage>com.isea533.mybatis.mapper</targetMapperPackage>
<targetModelPackage>com.isea533.mybatis.model</targetModelPackage>
<!-- XML生成路徑 -->
<targetResourcesProject>${basedir}/src/main/resources</targetResourcesProject>
<targetXMLPackage>mapper</targetXMLPackage>
<!-- 編譯jdk版本 -->
<jdk.version>1.6</jdk.version>
<!-- 依賴版本 -->
<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依賴-->
<dependency>
<groupId>org.codehaus.castor</groupId>
<artifactId>castor-xml</artifactId>
<version>1.3.3</version>
</dependency>
<!--spring-json依賴-->
<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依賴-->
<dependency>
<groupId>org.aspectj</groupId>
<artifactId>aspectjweaver</artifactId>
<version>1.8.2</version>
</dependency>
<!--上傳文件-->
<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>${mybatis.spring.version}</version>
</dependency>
<!-- Mybatis Generator -->
<dependency>
<groupId>org.mybatis.generator</groupId>
<artifactId>mybatis-generator-core</artifactId>
<version>1.3.2</version>
<scope>compile</scope>
<optional>true</optional>
</dependency>
<!--分頁插件-->
<dependency>
<groupId>com.github.pagehelper</groupId>
<artifactId>pagehelper</artifactId>
<version>${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
">
<!-- 配置包掃描 -->
<context:component-scan base-package="com.krry"></context:component-scan>
<!-- 導(dǎo)入外部資源文件 -->
<context:property-placeholder location="classpath:jdbc.properties" />
<!-- 配置druid數(shù)據(jù)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>
<!-- 注冊(cè)事務(wù)管理器 -->
<bean id="txMgr"
class="org.springframework.jdbc.datasource.DataSourceTransactionManager">
<property name="dataSource" ref="dataSource"></property>
</bean>
<!-- 開啟事務(wù)注解驅(qū)動(dòng) -->
<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">
<!-- 這里的幾個(gè)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>
<!-- 配置可以整體掃描Mapper的一個(gè)掃描器 -->
<bean class="org.mybatis.spring.mapper.MapperScannerConfigurer">
<!--如果有多個(gè)報(bào)路徑,用逗號(hào)分開即可 -->
<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> <!-- 全局映射器啟用緩存 --> <setting name="cacheEnabled" value="true" /> <!-- 查詢時(shí)，關(guān)閉關(guān)聯(lián)對(duì)象即時(shí)加載以提高性能 --> <setting name="lazyLoadingEnabled" value="true" /> <!-- 設(shè)置關(guān)聯(lián)對(duì)象加載的形態(tài)，此處為按需加載字段(加載字段由SQL指 定)，不會(huì)加載關(guān)聯(lián)表的所有字段，以提高性能 --> <setting name="aggressiveLazyLoading" value="false" /> <!-- 對(duì)于未知的SQL查詢，允許返回不同的結(jié)果集以達(dá)到通用的效果 --> <setting name="multipleResultSetsEnabled" value="true" /> <!-- 允許使用列標(biāo)簽代替列名 --> <setting name="useColumnLabel" value="true" /> <!-- 允許使用自定義的主鍵值(比如由程序生成的UUID 32位編碼作為鍵值)，數(shù)據(jù)表的PK生成策略將被覆蓋 --> <setting name="useGeneratedKeys" value="true" /> <!-- 給予被嵌套的resultMap以字段-屬性的映射支持 --> <setting name="autoMappingBehavior" value="FULL" /> <!-- 對(duì)于批量更新操作緩存SQL以提高性能 --> <setting name="defaultExecutorType" value="BATCH" /> <!-- 數(shù)據(jù)庫超過25000秒仍未響應(yīng)則超時(shí) --> <setting name="defaultStatementTimeout" value="25" /> <setting name="lazyLoadTriggerMethods" value="equals,clone,hashCode,toString"/> </settings> <typeAliases> <!--自定義user對(duì)象的別名 --> <!-- <typeAlias type="com.krry.mybatis.sysmanage.entity.User" alias="user"/> --> <!-- 批量定義別名 --> <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
">
<!-- 開啟注解模式驅(qū)動(dòng) -->
<bean class="org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerAdapter" />
<!-- 開啟mvc的注解模式 user 還會(huì)注冊(cè)一個(gè)ConversionService 子類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">
<!-- 處理responseBody 里面日期類型 -->
<property name="dateFormat">
<bean class="java.text.SimpleDateFormat">
<constructor-arg type="java.lang.String" value="yyyy-MM-dd HH:mm:ss" />
</bean>
</property>
<!-- 為null字段時(shí)不顯示 -->
<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>
<!-- 掃包 -->
<context:component-scan base-package="com.krry.controller"></context:component-scan>
<!--對(duì)靜態(tài)資源文件的訪問 必須要設(shè)置，因?yàn)樵趕pringmvc的配置中配置了/匹配所有請(qǐng)求，
此工程所有的請(qǐng)求(.do ,addUser,js/image/css)都會(huì)被springmvc解析,
必須對(duì)所有的靜態(tài)資源文件進(jìn)行過濾放行 -->
<!-- 靜態(tài)資源過濾 下面二選一-->
<!--<mvc:default-servlet-handler/> -->
<mvc:resources mapping="/resource/**" location="/resource/" />
<!-- 視圖渲染 jsp/freemaker/velocity-->
<bean class="org.springframework.web.servlet.view.InternalResourceViewResolver">
<!-- 制定頁面存放的路徑 -->
<property name="prefix" value="/WEB-INF/pages/"></property>
<!-- 文件的后綴 -->
<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>
實(shí)體類：Country.java
package com.krry.entity;
public class Country {
/**
* 主鍵
*/
private Integer id;
/**
* 名稱
*/
private String countryname;
/**
* 代碼
*/
private String countrycode;
public Country(Integer id, String countryname, String countrycode) {
this.id = id;
this.countryname = countryname;
this.countrycode = countrycode;
}
/**
* 獲取主鍵
*
* @return Id - 主鍵
*/
public Integer getId() {
return id;
}
/**
* 設(shè)置主鍵
*
* @param id 主鍵
*/
public void setId(Integer id) {
this.id = id;
}
/**
* 獲取名稱
*
* @return countryname - 名稱
*/
public String getCountryname() {
return countryname;
}
/**
* 設(shè)置名稱
*
* @param countryname 名稱
*/
public void setCountryname(String countryname) {
this.countryname = countryname;
}
/**
* 獲取代碼
*
* @return countrycode - 代碼
*/
public String getCountrycode() {
return countrycode;
}
/**
* 設(shè)置代碼
*
* @param countrycode 代碼
*/
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;
}
}
持久層：CountryMapper.java
package com.krry.mapper;
import java.util.List;
import com.krry.entity.Country;
/**
*
* Mapper：操作數(shù)據(jù)庫
* @author krry
* @version 1.0.0
*
*/
public interface CountryMapper {
/**
* 查詢
* @param params
* @return
*/
public List<Country> finds();
/**
* 計(jì)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" > <!-- 分頁查詢 --> <select id="finds" resultType="country"> SELECT id, countryname, countrycode FROM country </select> <!-- 查詢博客數(shù)量 --> <select id="counts" resultType="long"> SELECT count(*) FROM country </select> </mapper>
業(yè)務(wù)層接口：
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層：處理業(yè)務(wù)邏輯（impl里面實(shí)現(xiàn)）
* @author asusaad
*
*/
public interface ICountryService {
/**
* 分頁查詢所有博客
* @param params 分頁參數(shù) pageNo（頁碼），pageSize（每頁查詢數(shù)目）
* @return
*/
public PageInfo<Country> finds(Params params);
/**
* 計(jì)算博客數(shù)量
* @param params
* @return
*/
public long counts();
}
業(yè)務(wù)層實(shí)現(xiàn)類
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;
/**
* 實(shí)現(xiàn)service層接口
* @author asusaad
*
*/
@Service
public class CountryService implements ICountryService{
@Autowired
private CountryMapper countryMapper;
/**
* 查詢
*/
public PageInfo<Country> finds(Params params) {
//查詢
int pageNo = params.getPageNo();
int pageSize = params.getPageSize();
PageHelper.startPage(pageNo, pageSize);
List<Country> blogs = countryMapper.finds();
//用PageInfo對(duì)結(jié)果進(jìn)行包裝
PageInfo<Country> pageInfo = new PageInfo<Country>(blogs);
return pageInfo;
}
/**
* 計(jì)算
* @param params
* @return
*/
public long counts(){
long couts = countryMapper.counts();
return couts;
}
}
控制層：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層，作為請(qǐng)求轉(zhuǎn)發(fā)
* @author asusaad
*
*/
@Controller //表示是多例模式，每個(gè)用戶返回的web層是不一樣的
@RequestMapping("/index")
public class KrryController {
@Autowired
private ICountryService countryService;
/**
* 首頁，并且分頁查詢
* @return
*/
@RequestMapping("/index")
public ModelAndView index(Params params){
ModelAndView modelAndView = new ModelAndView();
//一開始第一頁，查詢10條
params.setPageNo(1);
params.setPageSize(10);
PageInfo<Country> pageInfo = countryService.finds(params);
List<Country> clist = pageInfo.getList();
//查詢數(shù)量
long couts = countryService.counts();
modelAndView.addObject("clist", clist);
modelAndView.addObject("couts", couts);
modelAndView.setViewName("index");
return modelAndView;
}
/**
* ajax請(qǐng)求 的 分頁查詢
* @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?jī)?nèi)容，希望對(duì)大家的學(xué)習(xí)有所幫助，也希望大家多多支持腳本之家。
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