• JAVA List集合转Page(分页对象)


    /**
     * @version 1.0
     * @author: fwjia
     */
    import java.util.List;
    
    public class PageModel<T> {
        /***
         * 当前页
         */
        private int page = 1;
    
        /***
         * 总页数
         */
        public int totalPages = 0;
    
        /***
         * 每页数据条数
         */
        private int pageRecorders;
    
        /***
         * 总页数
         */
        private int totalRows = 0;
    
        /***
         * 每页的起始数
         */
        private int pageStartRow = 0;
    
        /***
         * 每页显示数据的终止数
         */
        private int pageEndRow = 0;
    
        /***
         * 是否有下一页
         */
        private boolean hasNextPage = false;
    
        /***
         * 是否有前一页
         */
        private boolean hasPreviousPage = false;
    
        /***
         * 数据集合
         */
        private List<T> list;
    
    
        public PageModel(List<T> list, int pageRecorders) {
            // 通过对象集,记录总数划分
            init(list, pageRecorders);
        }
    
        /** *//**
         * 初始化list,并告之该list每页的记录数
         * @param list 数据几个
         * @param pageRecorders 一页显示多少数据
         */
        public void init(List<T> list, int pageRecorders) {
            this.pageRecorders = pageRecorders;
            this.list = list;
            totalRows = list.size();
            hasPreviousPage = false;
            if ((totalRows % pageRecorders) == 0) {
                totalPages = totalRows / pageRecorders;
            } else {
                totalPages = totalRows / pageRecorders + 1;
            }
    
            if (page >= totalPages) {
                hasNextPage = false;
            } else {
                hasNextPage = true;
            }
    
            if (totalRows < pageRecorders) {
                this.pageStartRow = 0;
                this.pageEndRow = totalRows;
            } else {
                this.pageStartRow = 0;
                this.pageEndRow = pageRecorders;
            }
        }
    
    
        // 判断要不要分页
        public boolean isNext() {
            return list.size() > 5;
        }
    
        public void setHasPreviousPage(boolean hasPreviousPage) {
            this.hasPreviousPage = hasPreviousPage;
        }
    
        public String toString(int temp) {
            String str = Integer.toString(temp);
            return str;
        }
    
        public void description() {
    
            String description = "共有数据数:" + this.getTotalRows() +
    
                    "共有页数: " + this.getTotalPages() +
    
                    "当前页数为:" + this.getPage() +
    
                    " 是否有前一页: " + this.isHasPreviousPage() +
    
                    " 是否有下一页:" + this.isHasNextPage() +
    
                    " 开始行数:" + this.getPageStartRow() +
    
                    " 终止行数:" + this.getPageEndRow();
    
            System.out.println(description);
        }
    
        public List getNextPage() {
            page = page + 1;
    
            disposePage();
    
            System.out.println("用户凋用的是第" + page + "页");
            this.description();
            return getObjects(page);
        }
    
        /**
         * 处理分页
         */
        private void disposePage() {
    
            if (page == 0) {
                page = 1;
            }
    
            if ((page - 1) > 0) {
                hasPreviousPage = true;
            } else {
                hasPreviousPage = false;
            }
    
            if (page >= totalPages) {
                hasNextPage = false;
            } else {
                hasNextPage = true;
            }
        }
    
        public List getPreviousPage() {
    
            page = page - 1;
    
            if ((page - 1) > 0) {
                hasPreviousPage = true;
            } else {
                hasPreviousPage = false;
            }
            if (page >= totalPages) {
                hasNextPage = false;
            } else {
                hasNextPage = true;
            }
            this.description();
            return getObjects(page);
        }
    
        /**
         * 获取第几页的内容
         *
         * @param page 当前页面
         * @return
         */
        public List<T> getObjects(int page) {
            if(page == 0){
                this.setPage(1);
            }
            else{
                this.setPage(page);
            }
            this.disposePage();
            if (page * pageRecorders < totalRows) {
                // 判断是否为最后一页
                pageEndRow = page * pageRecorders;
                pageStartRow = pageEndRow - pageRecorders;
            } else {
                pageEndRow = totalRows;
                pageStartRow = pageRecorders * (totalPages - 1);
            }
    
            List<T> objects = null;
            if (!list.isEmpty()) {
                objects = list.subList(pageStartRow, pageEndRow);
            }
            //this.description();
            return objects;
        }
    
        public List<T> getFistPage() {
            if (this.isNext()) {
                return list.subList(0, pageRecorders);
            } else {
                return list;
            }
        }
    
        public boolean isHasNextPage() {
            return hasNextPage;
        }
    
    
        public void setHasNextPage(boolean hasNextPage) {
            this.hasNextPage = hasNextPage;
        }
    
    
        public List getList() {
            return list;
        }
    
    
        public void setList(List list) {
            this.list = list;
        }
    
    
        public int getPage() {
            return page;
        }
    
    
        public void setPage(int page) {
            this.page = page;
        }
    
    
        public int getPageEndRow() {
            return pageEndRow;
        }
    
    
        public void setPageEndRow(int pageEndRow) {
            this.pageEndRow = pageEndRow;
        }
    
    
        public int getPageRecorders() {
            return pageRecorders;
        }
    
    
        public void setPageRecorders(int pageRecorders) {
            this.pageRecorders = pageRecorders;
        }
    
    
        public int getPageStartRow() {
            return pageStartRow;
        }
    
    
        public void setPageStartRow(int pageStartRow) {
            this.pageStartRow = pageStartRow;
        }
    
    
        public int getTotalPages() {
            return totalPages;
        }
    
    
        public void setTotalPages(int totalPages) {
            this.totalPages = totalPages;
        }
    
    
        public int getTotalRows() {
            return totalRows;
        }
    
    
        public void setTotalRows(int totalRows) {
            this.totalRows = totalRows;
        }
    
    
        public boolean isHasPreviousPage() {
            return hasPreviousPage;
        }
    
    }
    

      测试类TestPagerModel 

    import java.util.ArrayList;
    import java.util.List;
    
    /**
     * @version 1.0
     * @author: fwjia
     */
    public class TestPagerModel {
    
        public static void main(String args[]) {
            List<String> list = new ArrayList<String>();
            list.add("a");
            list.add("b");
            list.add("c");
            list.add("d");
            list.add("e");
            list.add("f");
            list.add("g");
            list.add("h");
            list.add("h");
            list.add("i");
            list.add("j");
            list.add("k");
            list.add("l");
            list.add("m");
            PageModel<String> pm = new PageModel(list, 5);
    
            List<String> sublist = pm.getObjects(2);
            for(int i = 0; i < sublist.size(); i++) {
                System.out.println(sublist.get(i));
            }
        }
    
    }
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  • 原文地址:https://www.cnblogs.com/jiafuwei/p/10096183.html
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