引入依赖
<!--分页插件开始-->
<dependency>
<groupId>com.github.pagehelper</groupId>
<artifactId>pagehelper</artifactId>
<version>5.2.0</version>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-autoconfigure</artifactId>
<version>2.3.1.RELEASE</version>
</dependency>
<dependency>
<groupId>com.github.pagehelper</groupId>
<artifactId>pagehelper-spring-boot-starter</artifactId>
<version>1.3.0</version>
</dependency>
<!--分页插件结束-->
配置application.properties
# 配置分页插件pagehelper
pagehelper.helper-dialect=mysql
pagehelper.reasonable=true
pagehelper.support-methods-arguments=true
pagehelper.params=count=countSql
Service层
import com.github.pagehelper.Page;
import com.github.pagehelper.PageHelper;
public List<Video> listVideo() {
try
{
// Object cacheObj=baseCache.getTenMinteCache().get(CacheKeyManager.INDEX_VIDEO_LIST_KEY,()->{
Page<Object> objects = PageHelper.offsetPage(1, 4, true);
List<Video> videos = videoMapper.ListVideo();
System.out.println(objects);
//System.out.println("=========="+videos);
return videos;
// });
// if (cacheObj instanceof List){
// return (List<Video>)cacheObj;
// }
}catch (Exception e){
e.printStackTrace();
}
return null;
}
PageMethod.java
PageHelper还有很多其他方法，可以尝试用其他的方法
/*
* The MIT License (MIT)
*
* Copyright (c) 2014-2017 abel533@gmail.com
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*/
package com.github.pagehelper.page;
import com.github.pagehelper.ISelect;
import com.github.pagehelper.Page;
import com.github.pagehelper.util.PageObjectUtil;
import java.util.Properties;
/**
* 基础分页方法
*
* @author liuzh
*/
public abstract class PageMethod {
protected static final ThreadLocal<Page> LOCAL_PAGE = new ThreadLocal<Page>();
protected static boolean DEFAULT_COUNT = true;
/**
* 设置 Page 参数
*
* @param page
*/
protected static void setLocalPage(Page page) {
LOCAL_PAGE.set(page);
}
/**
* 获取 Page 参数
*
* @return
*/
public static <T> Page<T> getLocalPage() {
return LOCAL_PAGE.get();
}
/**
* 移除本地变量
*/
public static void clearPage() {
LOCAL_PAGE.remove();
}
/**
* 获取任意查询方法的count总数
*
* @param select
* @return
*/
public static long count(ISelect select) {
Page<?> page = startPage(1, -1, true);
select.doSelect();
return page.getTotal();
}
/**
* 开始分页
*
* @param params
*/
public static <E> Page<E> startPage(Object params) {
Page<E> page = PageObjectUtil.getPageFromObject(params, true);
//当已经执行过orderBy的时候
Page<E> oldPage = getLocalPage();
if (oldPage != null && oldPage.isOrderByOnly()) {
page.setOrderBy(oldPage.getOrderBy());
}
setLocalPage(page);
return page;
}
/**
* 开始分页
*
* @param pageNum 页码
* @param pageSize 每页显示数量
*/
public static <E> Page<E> startPage(int pageNum, int pageSize) {
return startPage(pageNum, pageSize, DEFAULT_COUNT);
}
/**
* 开始分页
*
* @param pageNum 页码
* @param pageSize 每页显示数量
* @param count 是否进行count查询
*/
public static <E> Page<E> startPage(int pageNum, int pageSize, boolean count) {
return startPage(pageNum, pageSize, count, null, null);
}
/**
* 开始分页
*
* @param pageNum 页码
* @param pageSize 每页显示数量
* @param orderBy 排序
*/
public static <E> Page<E> startPage(int pageNum, int pageSize, String orderBy) {
Page<E> page = startPage(pageNum, pageSize);
page.setOrderBy(orderBy);
return page;
}
/**
* 开始分页
*
* @param pageNum 页码
* @param pageSize 每页显示数量
* @param count 是否进行count查询
* @param reasonable 分页合理化,null时用默认配置
* @param pageSizeZero true且pageSize=0时返回全部结果，false时分页,null时用默认配置
*/
public static <E> Page<E> startPage(int pageNum, int pageSize, boolean count, Boolean reasonable, Boolean pageSizeZero) {
Page<E> page = new Page<E>(pageNum, pageSize, count);
page.setReasonable(reasonable);
page.setPageSizeZero(pageSizeZero);
//当已经执行过orderBy的时候
Page<E> oldPage = getLocalPage();
if (oldPage != null && oldPage.isOrderByOnly()) {
page.setOrderBy(oldPage.getOrderBy());
}
setLocalPage(page);
return page;
}
/**
* 开始分页
*
* @param offset 起始位置，偏移位置
* @param limit 每页显示数量
*/
public static <E> Page<E> offsetPage(int offset, int limit) {
return offsetPage(offset, limit, DEFAULT_COUNT);
}
/**
* 开始分页
*
* @param offset 起始位置，偏移位置
* @param limit 每页显示数量
* @param count 是否进行count查询
*/
public static <E> Page<E> offsetPage(int offset, int limit, boolean count) {
Page<E> page = new Page<E>(new int[]{offset, limit}, count);
//当已经执行过orderBy的时候
Page<E> oldPage = getLocalPage();
if (oldPage != null && oldPage.isOrderByOnly()) {
page.setOrderBy(oldPage.getOrderBy());
}
setLocalPage(page);
return page;
}
/**
* 排序
*
* @param orderBy
*/
public static void orderBy(String orderBy) {
Page<?> page = getLocalPage();
if (page != null) {
page.setOrderBy(orderBy);
} else {
page = new Page();
page.setOrderBy(orderBy);
page.setOrderByOnly(true);
setLocalPage(page);
}
}
/**
* 设置参数
*
* @param properties 插件属性
*/
protected static void setStaticProperties(Properties properties){
//defaultCount，这是一个全局生效的参数，多数据源时也是统一的行为
if(properties != null){
DEFAULT_COUNT = Boolean.valueOf(properties.getProperty("defaultCount", "true"));
}
}
}
效果
