自己写的分页组件
1.封装类代码如下：
2.主要由一个类进行了封装，servlet进行相关参数的设置。Servlet代码如下：
import java.sql.SQLException;
import java.util.List;
import javax.swing.text.TableView.TableRow;
@SuppressWarnings("unchecked")
public class PaginationModule {
private int NumPerPage = 15; //每页显示的记录条数
private int currentPage = 0; //当前显示页面
private int totalNums = 0; //共有多少条数据
private int totalPages = 0; //可以分成多少个页面
private int cfPage = 0; //要显示页面的第一条数据
private int clPage = 0; //要显示页面的最后一条数据
private int firstOfPage = 0; //显示第一页面
private int prevOfPage = 0; //显示最后一页面
private int lastOfPage = 0; //显示前一页面
private int nextOfPage = 0; //显示下一页面
private String keyword = null; //关键字查询
private String tabelName = ""; //访问数据库中的一个表或子查询
private String condition = ""; //条件查询
private String orderby = ""; //按某字段排序返回结果
private boolean desc = false; //是否按逆序进行排序
private String url = ""; //页面的请求路径
private boolean flag = false; //是否在数据前面显示4个按钮
private List list = null; //数据存储于list中
private TableRowIterator tr = null; //返回一个TableRowIterator
private Context context = null;
public PaginationModule(Context context) {
this.context = context;
}
public void setNumPerPage(int numPerPage) {
NumPerPage = numPerPage;
}
public void setTabelName(String tabelName) throws SQLException {
this.tabelName = tabelName;
if(!"".equals(this.tabelName)){
this.initTotalNum();
}
}
public void setTabelName(String tabelName, String condition)throws SQLException {
this.tabelName = tabelName;
//condition = condition.trim().replaceAll("'", "");
String temp = condition;
String tp = "";
int ii = temp.indexOf("%");
if(ii != -1) {
do {
int i = temp.indexOf("%");
String sub1 = temp.substring(0, i+1);
String sub2 = temp.substring(i+1, temp.length());
int j = sub2.indexOf("%");
tp += sub1;
if(j != 0) {
String ktemp = sub2.substring(0, j).trim().replaceAll("'", "");
tp += ktemp;
}
tp += "%";
temp = sub2.substring(j+1, sub2.length());
} while(temp.indexOf("%") > 0);
}
temp = tp + temp;
this.condition = temp;
if(!"".equals(this.condition)){
this.initTotalNum(this.condition);
} else if(!"".equals(this.tabelName)){
this.initTotalNum();
}
}
public void setCurrentPage(int currentPage) throws SQLException {
if(currentPage >= this.totalPages) {
currentPage = this.totalPages - 1;
}
if(currentPage < 0) {
currentPage = 0;
}
this.cfPage = currentPage*NumPerPage+1;
this.clPage = currentPage*NumPerPage+NumPerPage > totalNums ? totalNums:currentPage*NumPerPage+NumPerPage;
this.firstOfPage = currentPage == 0 ? -1 : 0;
this.prevOfPage = currentPage == 0 ? -1 : currentPage-1;
this.lastOfPage = totalPages == 1 ? -1 : totalPages-1;
this.nextOfPage = totalPages > 1 ? currentPage + 1 : -1;
this.currentPage = currentPage;
if(!"".equals(this.condition)){
this.initdata(this.condition);
} else if(!"".equals(this.tabelName)){
this.initdata();
}
}
public void setUrl(String url) {
this.url = url;
}
public PaginationModule() {
}
public PaginationModule(int numPerPage, int currentPage, String table, String url, Context context) {
this.NumPerPage = numPerPage;
this.tabelName = table;
}
//推荐使用此构造方法
public PaginationModule(int numPerPage, int currentPage, int totalNums, List list, String url, Context context) {
this.NumPerPage = numPerPage;
this.currentPage = currentPage;
this.totalNums = totalNums;
this.list = list;
this.totalPages = (totalNums+NumPerPage-1)/NumPerPage;
this.cfPage = currentPage*NumPerPage+1;
this.clPage = currentPage*NumPerPage+NumPerPage > totalNums ? totalNums:currentPage*NumPerPage+NumPerPage;
this.firstOfPage = currentPage == 0 ? -1 : 0;
this.prevOfPage = currentPage == 0 ? -1 : currentPage-1;
this.lastOfPage = totalPages == 1 ? -1 : totalPages-1;
this.nextOfPage = totalPages > 1 ? currentPage + 1 : -1;
this.url = url;
this.context = context;
}
public int getNumPerPage() {
return NumPerPage;
}
public int getCurrentPage() {
return currentPage;
}
public void initdata() throws SQLException{
Object[] parameters = new Integer[2];
parameters[0] = this.cfPage;
parameters[1] = this.clPage;
String sql = "select rn, ne.* from (select rownum rn,n.* from(select * from ";
if(this.desc) {
sql = sql + this.tabelName + " order by " + this.orderby +" desc ) n) ne where rn between ? and ?";
} else if(!"".equals(this.orderby)) {
sql = sql + this.tabelName + " order by " + this.orderby +" ) n) ne where rn between ? and ?";
} else {
sql = sql + this.tabelName + " ) n) ne where rn between ? and ?";
}
this.tr = DatabaseManager.query(context, sql, parameters);
}
public void initdata(String condition) throws SQLException{
Object[] parameters = new Integer[2];
parameters[0] = this.cfPage;
parameters[1] = this.clPage;
String sql = "select rn, ne.* from (select rownum rn,n.* from(select * from ";
if(this.desc) {
sql = sql + this.tabelName + " where " + condition + " order by " + this.orderby + " desc ) n) ne where rn between ? and ?";
} else if(!"".equals(this.orderby)) {
sql = sql + this.tabelName + " where " + condition +
" order by " + this.orderby + " ) n) ne where rn between ? and ?";
} else {
sql = sql + this.tabelName + " where " + condition + ") n) ne where rn between ? and ?";
}
this.tr = DatabaseManager.query(context, sql, parameters);
}
public void initTotalNum() throws SQLException{
String sql = "select count(*) num from " + this.tabelName;
TableRowIterator tr = DatabaseManager.query(context, sql);
if(tr.hasNext()) {
this.totalNums = tr.next().getIntColumn("num");
}
this.totalPages = (totalNums+NumPerPage-1)/NumPerPage;
}
public void initTotalNum(String condition) throws SQLException{
String sql = "select count(*) num from " + this.tabelName + " where " + condition;
TableRowIterator tr = DatabaseManager.query(context, sql);
if(tr.hasNext()) {
this.totalNums = tr.next().getIntColumn("num");
}
this.totalPages = (totalNums+NumPerPage-1)/NumPerPage;
}
public TableRowIterator executeSql(Context context, String sql ) throws SQLException{
return DatabaseManager.query(context, sql);
}
public int getCfPage() {
return cfPage;
}
public void setCfPage(int cfPage) {
this.cfPage = cfPage;
}
public int getClPage() {
return clPage;
}
public void setClPage(int clPage) {
this.clPage = clPage;
}
public int getTotalNums() {
return totalNums;
}
public void setTotalNums(int totalNums) {
this.totalNums = totalNums;
this.totalPages = (totalNums+NumPerPage-1)/NumPerPage;
}
public int getTotalPages() {
return totalPages;
}
public void setTotalPages(int totalPages) {
this.totalPages = totalPages;
}
public List getList() {
return list;
}
public void setList(List list) {
this.list = list;
}
public int getFirstOfPage() {
return firstOfPage;
}
public void setFirstOfPage(int firstOfPage) {
this.firstOfPage = firstOfPage;
}
public int getPrevOfPage() {
return prevOfPage;
}
public void setPrevOfPage(int prevOfPage) {
this.prevOfPage = prevOfPage;
}
public int getLastOfPage() {
return lastOfPage;
}
public void setLastOfPage(int lastOfPage) {
this.lastOfPage = lastOfPage;
}
public int getNextOfPage() {
return nextOfPage;
}
public void setNextOfPage(int nextOfPage) {
this.nextOfPage = nextOfPage;
}
public String getUrl() {
return url;
}
public boolean isFlag() {
return flag;
}
public void setFlag(boolean flag) {
this.flag = flag;
}
public TableRowIterator getTr() {
return tr;
}
public void setCondition(String condition) {
this.condition = condition;
}
public void setContext(Context context) {
this.context = context;
}
public void setOrderby(String orderby, boolean desc) {
this.orderby = orderby;
this.desc = desc;
}
public String getKeyword() {
return keyword;
}
public void setKeyword(String keyword) {
keyword = keyword.trim().replaceAll("'", "");
this.keyword = keyword;
}
}
2.主要由一个类进行了封装，servlet进行相关参数的设置。Servlet代码如下：
PaginationModule pagm = new PaginationModule(c);
int currentPage = 0;
if (request.getParameter("curp") != null) {
currentPage = Integer.parseInt(request.getParameter("curp"));
}
pagm.setOrderby("created_date", true);
String keyword = request.getParameter("conditionvalue") == null ? "":request.getParameter("conditionvalue");
pagm.setTabelName("news", "title like '%" + keyword + "%' ");
pagm.setKeyword(keyword);
try {
if (request.getParameter("jump_page") != null) {
currentPage = Integer.parseInt(request.getParameter("jump_page")) - 1;
}
} catch (NumberFormatException e) {
currentPage = 0;
}
pagm.setCurrentPage(currentPage);
TableRowIterator tr = pagm.getTr();
if(tr != null) {
List<News> newslist = new ArrayList<News>();
while(tr.hasNext()) {
TableRow trw = tr.next();
if(trw != null) {
newslist.add( new News(trw));
}
}
pagm.setList(newslist);
}
pagm.setUrl("news-edit?conditionvalue=" + java.net.URLEncoder.encode(keyword, Constants.DEFAULT_ENCODING) + "&");
request.setAttribute("paginationModule", pagm);3.jsp页面显示：
<%
PaginationModule pmodule = (PaginationModule)request.getAttribute("paginationModule");
List<News> newslist = pmodule.getList();
String keyword = pmodule.getKeyword();
%>
<% if (pmodule.getFirstOfPage() > -1) { %>
<a href="<%=request.getContextPath() %>/<%=pmodule.getUrl() %>curp=0" ><img border="0" src="<%= request.getContextPath() %>/images/btn_prev2-1.gif" width="12" height="9" alt=""/></a>
<% } else { %>
<img border="0" src="<%= request.getContextPath() %>/images/btn_prev2.gif" width="12" height="9" alt=""/>
<% } %>
<% if (pmodule.getCurrentPage() > 0) { %>
<a href="<%=request.getContextPath() %>/<%=pmodule.getUrl() %>curp=<%=pmodule.getPrevOfPage() %>" ><img border="0" src="<%= request.getContextPath() %>/images/btn_prev-1.gif" width="5" height="9" alt=""/></a>
<% } else { %>
<img border="0" src="<%= request.getContextPath() %>/images/btn_prev.gif" width="5" height="9" alt=""/>
<% } %>
<fmt:message key="jsp.general.showresults">
<fmt:param value="<%= Integer.toString(pmodule.getCfPage()) %>"/>
<fmt:param value="<%= Integer.toString(pmodule.getClPage()) %>"/>
<fmt:param value="<%= Integer.toString(pmodule.getTotalNums()) %>"/>
<fmt:param value="<%= Integer.toString(pmodule.getCurrentPage()+1) %>" />
<fmt:param value="<%= Integer.toString(pmodule.getTotalPages()) %>" />
</fmt:message>
<% if (pmodule.getNextOfPage()>-1 && pmodule.getCurrentPage() < pmodule.getTotalPages() -1) { %>
<a href="<%=request.getContextPath() %>/<%=pmodule.getUrl() %>curp=<%=pmodule.getNextOfPage() %>" ><img border="0" src="<%= request.getContextPath() %>/images/btn_next-1.gif" width="5" height="9" alt=""/></a>
<% } else { %>
<img border="0" src="<%= request.getContextPath() %>/images/btn_next.gif" width="5" height="9" alt=""/>
<% } %>
<%-- Last Page --%>
<% if (pmodule.getLastOfPage()>-1 && pmodule.getCurrentPage() < pmodule.getTotalPages() -1) { %>
<a href="<%=request.getContextPath() %>/<%=pmodule.getUrl() %>curp=<%=pmodule.getLastOfPage() %>" ><img border="0" src="<%= request.getContextPath() %>/images/btn_next2-1.gif" width="12" height="9" alt=""/></a>
<% } else { %>
<img border="0" src="<%= request.getContextPath() %>/images/btn_next2.gif" width="12" height="9" alt=""/>
<% } %>
</td><td align="right">
<input id="jump_page" name="jump_page" onkeypress="javascript:return disableEnterKey(event);" class="bd" size="3" maxlength="45" value=""/>
<input type="submit" class="btn" name="submit_search" value="<fmt:message key="jsp.page.goto"/>"/>
</td></tr>
</table></td></tr>
</tbody>
</table>
</div>
</form>
</div> <% }