第一种方法是用封装好的PageInfo封装数据,返回的结果已经把总个数,每页数据,当前页,每页个数都封装好了(推荐使用):
需要在POM文件导入依赖
<dependency>
<groupId>com.github.pagehelper</groupId>
<artifactId>pagehelper</artifactId>
<version>5.0.1</version>
</dependency>
/** * 处理List集合数据进行分页 * * @param currentPage 当前页 * @param pageSize 每页数据个数 * @param list 进行分页的数据 * @param <T> * @return
*/
public static <T> PageInfo<T> queryPageInfo(int currentPage, int pageSize, List<T> list) { int total = list.size(); if (total > pageSize) { int toIndex = pageSize * currentPage; if (toIndex > total) { toIndex = total; } list = list.subList(pageSize * (currentPage - 1), toIndex); } Page<T> page = new Page<>(currentPage, pageSize); page.addAll(list); page.setPages((total + pageSize - 1) / pageSize); page.setTotal(total); PageInfo<T> pageInfo = new PageInfo<>(page); return pageInfo; }
第二种方法是循环截取某个页面的数据:
/** * 处理List集合数据进行分页 * * @param currentPage 当前页 * @param pageSize 每页数据个数 * @param list 进行分页的数据 * @param <T> * @return
*/
public static <T> List<T> getPageInfo(int currentPage, int pageSize, List<T> list) { List<T> newList = new ArrayList<>(); if (list != null && list.size() > 0) { int currIdx = (currentPage > 1 ? (currentPage - 1) * pageSize : 0); for (int i = 0; i < pageSize && i < list.size() - currIdx; i++) { newList.add(list.get(currIdx + i)); } } return newList; }
完整测试类代码:
import java.util.ArrayList; import java.util.List; import com.github.pagehelper.Page; import com.github.pagehelper.PageInfo; public class TestListPage { public static void main(String[] args) { List<String> list = new ArrayList<>(); for (int i = 0; i < 10; i++) { list.add(i + 1 + ""); } int currentPage = 1; int pageSize = 3; List<String> pageInfo = getPageInfo(currentPage, pageSize, list); System.out.println("总条数:" + list.size()); System.out.print("数据:"); pageInfo.forEach(e -> System.out.print(e)); System.out.println(); System.out.println("当前页:" + currentPage); System.out.println("每页个数:" + pageSize); System.out.println("总页数:" + ((list.size() / pageSize) + 1)); System.out.println("==========================="); PageInfo<String> queryPageInfo = queryPageInfo(currentPage, pageSize, list); System.out.println("总条数:" + queryPageInfo.getTotal()); System.out.print("数据:"); queryPageInfo.getList().forEach(e -> System.out.print(e)); System.out.println(); System.out.println("当前页:" + queryPageInfo.getPageNum()); System.out.println("每页个数:" + queryPageInfo.getPageSize()); System.out.println("总页数:" + queryPageInfo.getPages()); } /** * 处理List集合数据进行分页 * * @param currentPage 当前页 * @param pageSize 每页数据个数 * @param list 进行分页的数据 * @param <T> * @return
*/
public static <T> List<T> getPageInfo(int currentPage, int pageSize, List<T> list) { List<T> newList = new ArrayList<>(); if (list != null && list.size() > 0) { int currIdx = (currentPage > 1 ? (currentPage - 1) * pageSize : 0); for (int i = 0; i < pageSize && i < list.size() - currIdx; i++) { newList.add(list.get(currIdx + i)); } } return newList; } /** * 处理List集合数据进行分页 * * @param currentPage 当前页 * @param pageSize 每页数据个数 * @param list 进行分页的数据 * @param <T> * @return
*/
public static <T> PageInfo<T> queryPageInfo(int currentPage, int pageSize, List<T> list) { int total = list.size(); if (total > pageSize) { int toIndex = pageSize * currentPage; if (toIndex > total) { toIndex = total; } list = list.subList(pageSize * (currentPage - 1), toIndex); } Page<T> page = new Page<>(currentPage, pageSize); page.addAll(list); page.setPages((total + pageSize - 1) / pageSize); page.setTotal(total); PageInfo<T> pageInfo = new PageInfo<>(page); return pageInfo; } }
测试结果展示: