ssh2分页

分页应该是在我们开发web应用时经常要做的工作，能够比较简洁的实现数据库和视图层的分页十分重要。

在数据库层利用Hibernate进行数据库的分页，将从数据库中查询出的数据封装为javabean；在视图层就可以方便的实现分页。

创建PageBean1.package mon.bean;2.3.import java.util.List;4.@SuppressWarnings("unchecked")5.public class PageBean {6.7.private List list; // 要返回的某一页的记录列表8.9.private int allRow; // 总记录数10.private int totalPage; // 总页数11.private int currentPage; // 当前页12.private int pageSize; // 每页记录数13.14.15.private boolean isFirstPage; // 是否为第一页16.private boolean isLastPage; // 是否为最后一页17.private boolean hasPreviousPage; // 是否有前一页18.private boolean hasNextPage; // 是否有下一页19.20.public List getList() {21.return list;22. }23.24.public void setList(List list) {25.this.list = list;26. }27.28.public int getAllRow() {29.return allRow;30. }31.32.public void setAllRow(int allRow) {33.this.allRow = allRow;34. }35.36.public int getTotalPage() {37.return totalPage;38. }39.40.public void setTotalPage(int totalPage) {41.this.totalPage = totalPage;42. }43.44.public int getCurrentPage() {45.return currentPage;46. }47.48.public void setCurrentPage(int currentPage) {49.this.currentPage = currentPage;50. }51.52.public int getPageSize() {53.return pageSize;54. }55.56.public void setPageSize(int pageSize) {57.this.pageSize = pageSize;58. }59.60./** */61./**62. * 初始化分页信息63. */64.public void init() {65.this.isFirstPage = isFirstPage();66.this.isLastPage = isLastPage();67.this.hasPreviousPage = isHasPreviousPage();68.this.hasNextPage = isHasNextPage();69. }70.71./** */72./**73. * 以下判断页的信息,只需getter方法(is方法)即可74. *75. * @return76. */77.78.public boolean isFirstPage() {79.return (currentPage == 1);// 如是当前页是第1页80. }81.public boolean isLastPage() {82.return currentPage == totalPage; //如果当前页是最后一页83.}84.public boolean isHasPreviousPage() {85.return currentPage != 1; //只要当前页不是第1页86.}87.public boolean isHasNextPage() {88.return currentPage != totalPage; //只要当前页不是最后1页89.}90./** */91./**92. * 计算总页数,静态方法,供外部直接通过类名调用93. *94. * @param pageSize95. * 每页记录数96. * @param allRow97. * 总记录数98. * @return 总页数99. */100.public static int countTotalPage(final int pageSize, final int a llRow) {101.int totalPage = allRow % pageSize == 0 ? allRow / pageSize : allRow102. / pageSize + 1;103.return totalPage;104. }105.106./** */107./**108. * 计算当前页开始记录109. *110. * @param pageSize111. * 每页记录数112. * @param currentPage113. * 当前第几页114. * @return 当前页开始记录号115. */116.public static int countOffset(final int pageSize, final int curr entPage) {117.final int offset = pageSize * (currentPage - 1);118.return offset;119. }120.121./** */122./**123. * 计算当前页,若为0或者请求的URL中没有"?page=",则用1代替124. *125. * @param page126. * 传入的参数(可能为空,即0,则返回1)127. * @return 当前页128. */129.public static int countCurrentPage(int page) {130.final int curPage = (page == 0 ? 1 : page);131.return curPage;132. }133.}在Dao的抽象接口BaseDao中添加方法1.public List queryForPage(final String hql, final int offset,2.final int length);在Dao的实现类JianSheDWDaoImpl中实现方法1.public List queryForPage(final String hql, final int offset,2.final int length) {3. List list = getHibernateTemplate().executeFind(new HibernateCallback() {4.5.public Object doInHibernate(Session session)6.throws HibernateException, SQLException {7. Query query = session.createQuery(hql);8. query.setFirstResult(offset);9. query.setMaxResults(length);10. List list = query.list();11.return list;12.13. }14. });15.16.return list;17. }在service抽象层接口JianSheDWService中添加方法1.public PageBean queryForPage(int pageSize,int currentPage);在service实现类中实现方法1.public PageBean queryForPage(int pageSize, int page) {2.final String hql = "from JianSheDWBean"; // 查询语句3.int allRow = this.baseDao.getAllRowCount(hql); // 总记录数4.int totalPage = PageBean.countTotalPage(pageSize, allRow); // 总页数5.final int offset = PageBean.countOffset(pageSize, page); //当前页开始记录6.final int length = pageSize; // 每页记录数7.final int currentPage = PageBean.countCurrentPage(page);8. List<JianSheDWBean> list = this.baseDao.queryForPage(hql, offset, length); // "一页"的记录9.10.// 把分页信息保存到Bean中11. PageBean pageBean = new PageBean();12. pageBean.setPageSize(pageSize);13. pageBean.setCurrentPage(currentPage);14. pageBean.setAllRow(allRow);15. pageBean.setTotalPage(totalPage);16. pageBean.setList(list);17. pageBean.init();18.return pageBean;19.20. }在视图层action中建立分页模型1.package com.fishing.action.lcq;2.3.4.5.import mon.bean.JianSheDWBean;6.import mon.bean.PageBean;7.import com.fishing.service.lcq.JianSheDWService;8.import com.opensymphony.xwork2.ActionSupport;9.10.@SuppressWarnings("serial")11.public class GetInfoJSDWListAction extends ActionSupport {12.13.private int page; // 第几页14.15.private PageBean pageBean; // 包含分布信息的bean16.17.private JianSheDWBean jianSheDWBean;18.// private PageBean page;19.private JianSheDWService jianSheDWService;20.21.public int getPage() {22.return page;23. }24.25.public void setPage(int page) {26.this.page = page;27. }28.29.public PageBean getPageBean() {30.return pageBean;31. }32.33.public void setPageBean(PageBean pageBean) {34.this.pageBean = pageBean;35. }36.37.public JianSheDWBean getJianSheDWBean() {38.return jianSheDWBean;39. }40.41.public void setJianSheDWBean(JianSheDWBean jianSheDWBean) {42.this.jianSheDWBean = jianSheDWBean;43. }44.45.public JianSheDWService getJianSheDWService() {46.return jianSheDWService;47. }48.49.public void setJianSheDWService(JianSheDWService jianSheDWService) {50.this.jianSheDWService = jianSheDWService;51. }52.53.@Override54.public String execute() throws Exception {55.56.//分页的pageBean,参数pageSize表示每页显示记录数,page为当前页57.this.pageBean = jianSheDWService.queryForPage(10, page);58.return SUCCESS;59. }60.}在jsp中编写分页1.<tr class="odd">2.<td>3. &nbsp;4.</td>5.<td>6.<s:if test="%{pageBean.currentPage == 1}">7.首页上一页8.</s:if>9.<s:else>10.<a href="jianguan/getJSDWInfos.action?page=1">首页</a>11.<a12.href="jianguan/getJSDWInfos.action?page=<s:property value="%{pageBean.cur rentPage-1}"/>" />上一页</a>13.14.</s:else>15.</td>16.<td>17.<s:if test="%{pageBean.currentPage != pageBean.totalPage}">18.19.<a20.href="jianguan/getJSDWInfos.action?page=<s:property value="%{pageBean.cur rentPage+1}"/>">下一页</a>21.<a22.href="jianguan/getJSDWInfos.action?page=<s:property value="pageBean.total Page"/>">尾页23.</a>24.</s:if>25.<s:else>26.下一页尾页27.</s:else>28.</td>29.30.<td>31.<div align="center">32.页次33.<s:property value="pageBean.currentPage"/>34. /35.<s:property value="pageBean.totalPage"/>36. &nbsp;&nbsp;&nbsp;共37.<s:property value="pageBean.allRow"/>38.记录39.</div>40.<div align="center"></div>41.</td>42.</tr>。