分页对象

 分页对象的构建：

import java.util.List;

/**

 * 封装一个页面类，也有的叫Pegenation 用户每次查询都创建这个对象

 * @author Administrator

 */

public class PageUtils {

       private int startRow;// 查询数据库是，当前页起始的第一条数据的索引

       private int pageSize; // 一个页面显示多少条数据

       private int currPage; // 当前页面的号码

 

       private int totalData; // 总共多少条数据

       private int totalPage; // 分页查看数据时总的页数

 

       private int nextPage; // 下一页

       private int prevPage; // 上一页

 

       private int firstPage; // 首页

       private int lastPage; // 尾页

 

       private int navCount; // 导航条数目

       private int startNav; // 导航条开始号码

       private int endNav; // 导航条结束号码

 

       private List pageData; // 当前页面的数据放在集合中

 

       public PageUtils(int pageSize, int currPage, int navCount, int totalData) {

              this.currPage = currPage; // 当前页

              this.pageSize = pageSize; // 每页多少条数据

              this.navCount = navCount; // 导航条数目

              this.totalData = totalData; // 总多少条数据

 

              this.totalPage = (int) Math.ceil(totalData * 1.0 / pageSize); // 总页数

              this.firstPage = 1; // 首页

              this.lastPage = this.totalPage; // 尾页

 

              if (this.navCount >= this.totalPage) { // 导航条数目大于总页数时，让导航条页数等于总页数

                     this.navCount = this.totalPage;

              }

 

              if (0 > currPage) { // 当前页号码小于0，就让当前页号码为第一页

                     this.currPage = 1;

              }

 

              if (currPage > (int) Math.ceil(totalData * 1.0 / pageSize)) { // 当前页号码大于总页数，就让当前页号码为最后一页数

                     this.currPage = this.lastPage;

              }

 

              this.startRow = (this.currPage - 1) * pageSize; // 当前页起始的第一条数据的号码

 

              this.prevPage = (this.currPage > 1 ? this.currPage - 1 : 1); // 上一页

              this.nextPage = (this.currPage < lastPage ? this.currPage + 1 : this.currPage); // 下一页

 

              this.startNav = this.currPage - this.navCount / 2; // 导航条开始页码

              this.endNav = this.startNav + this.navCount - 1; // 导航条结束页码

 

              if (this.currPage <= this.navCount / 2) { // 导航条开始页码过小时

                     this.startNav = this.firstPage;

                     this.endNav = this.navCount;

              }

 

              if (this.currPage >= (this.totalPage - this.navCount / 2 + 1)) { // 导航条开始页码过大时

                     this.startNav = this.totalPage - this.navCount + 1;

                     this.endNav = this.totalPage;

              }

 

       }

 

       public int getStartRow() {

              return startRow;

       }

 

       public void setStartRow(int startRow) {

              this.startRow = startRow;

       }

 

       public int getPageSize() {

              return pageSize;

       }

 

       public void setPageSize(int pageSize) {

              this.pageSize = pageSize;

       }

 

       public int getCurrPage() {

              return currPage;

       }

 

       public void setCurrPage(int currPage) {

              this.currPage = currPage;

       }

 

       public int getTotalData() {

              return totalData;

       }

 

       public void setTotalData(int totalData) {

              this.totalData = totalData;

       }

 

       public int getTotalPage() {

              return totalPage;

       }

 

       public void setTotalPage(int totalPage) {

              this.totalPage = totalPage;

       }

 

       public int getNextPage() {

              return nextPage;

       }

 

       public void setNextPage(int nextPage) {

              this.nextPage = nextPage;

       }

 

       public int getPrevPage() {

              return prevPage;

       }

 

       public void setPrevPage(int prevPage) {

              this.prevPage = prevPage;

       }

 

       public int getFirstPage() {

              return firstPage;

       }

 

       public void setFirstPage(int firstPage) {

              this.firstPage = firstPage;

       }

 

       public int getLastPage() {

              return lastPage;

       }

 

       public void setLastPage(int lastPage) {

              this.lastPage = lastPage;

       }

 

       public int getNavCount() {

              return navCount;

       }

 

       public void setNavCount(int navCount) {

              this.navCount = navCount;

       }

 

       public int getStartNav() {

              return startNav;

       }

 

       public void setStartNav(int statrNav) {

              this.startNav = statrNav;

       }

 

       public int getEndNav() {

              return endNav;

       }

 

       public void setEndNav(int endNav) {

              this.endNav = endNav;

       }

 

       public List getPageData() {

              return pageData;

       }

 

       public void setPageData(List pageData) {

              this.pageData = pageData;

       }

      

       // 测试

       public static void main(String[] args) {

　　　　　//设置每页数据pageSize为10条，当前页currPage为5, 导航条数目navCount为10个，totalData一个有56条数据

              PageUtils pageUtil = new PageUtils(10, 5, 10, 56);

              System.out.println("总页数" + pageUtil.totalPage);

              System.out.println("首页" + pageUtil.firstPage);

              System.out.println("尾页" + pageUtil.lastPage);

              System.out.println("当前页" + pageUtil.currPage);

              System.out.println("其实记录条" + pageUtil.startRow);

              System.out.println("上一页" + pageUtil.prevPage);

              System.out.println("下一页" + pageUtil.nextPage);

              System.out.println("导航条数目" + pageUtil.navCount);

              System.out.println("导航条开始页码" + pageUtil.startNav);

              System.out.println("导航条结束页码" + pageUtil.endNav);

       }

}