关于Servlet的List假分页

import java.util.ArrayList;
import java.util.List;
/**
*
* @ClassName: PageModel
* @Description: 从List中获取子list实行分页
*
*/
public class Page {
private int page = 1; // 当前页

public int totalPages = 0; // 总页数

private int pageRecorders;// 每页5条数据

private int totalRows = 0; // 总数据数

private int pageStartRow = 0;// 每页的起始数

private int pageEndRow = 0; // 每页显示数据的终止数

private boolean hasNextPage = false; // 是否有下一页

private boolean hasPreviousPage = false; // 是否有前一页

private List list;

// private Iterator it;

public Page(List list, int pageRecorders) {
init(list, pageRecorders);// 通过对象集，记录总数划分
}

/**
* 初始化list，并告之该list每页的记录数
* @param list
* @param pageRecorders
*/
public void init(List list, int pageRecorders) {
this.pageRecorders = pageRecorders;
this.list = list;
totalRows = list.size();
// it = list.iterator();
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
* @return
*/
public List 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 objects = null;
if (!list.isEmpty()) {
objects = list.subList(pageStartRow, pageEndRow);
}
//this.description();
return objects;
}

public List 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;
}

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");
Page pm = new Page(list, 1);

List sublist = pm.getObjects(3);
for(int i = 0; i < sublist.size(); i++) {
System.out.println(sublist.get(i));
}
//System.out.println("............"+sublist.get(0));

}

}

<pre name="code" class="html"><% 
<span>	</span>List saleGoodsList = (List) request.getAttribute("subList");
<span>	</span>for (Object list : saleGoodsList) {
<span>	</span>Goods goods = (Goods) list; 
%>
<tr>
<span>	</span><td>
<span>		</span><img  src="<%=goods.getPic_url()%>" width="120px" height="70px">
<span>	</span></td>
<span>	</span><td>
<span>		</span><%=goods.getTitle()%>
<span>		</span><br/>
<span>		</span><%=goods.getPrice()%>
<span>	</span></td>
</tr>
<%
<span>	</span>}
%>

<tr>
<td>
<span>	</span><a href="saleGoodsList?pageNow=1&pageSize=5" >首页</a>
<span>	</span><c:choose>
<span>	</span><c:when test="${pageNow==1}">
<span>		</span><a href="saleGoodsList?pageNow=1&pageSize=5">上一页</a>
<span>	</span></c:when>
<span>	</span><c:otherwise>
<span>		</span><a href="saleGoodsList?pageNow=${pageNow-1}&pageSize=5">上一页</a>
<span>	</span></c:otherwise>
<span>	</span></c:choose>
<span>	</span><c:choose>
<span>	</span><c:when test="${pageNow == totalPage}">
<span>		</span><a href="saleGoodsList?pageNow=${totalPage}&pageSize=5">下一页</a>
<span>	</span></c:when>
<span>	</span><c:otherwise>
<span>		</span><a href="saleGoodsList?pageNow=${pageNow+1}&pageSize=5">下一页</a>
<span>	</span> </c:otherwise>
<span>	</span></c:choose>
<span>	</span><a href="saleGoodsList?pageNow=<%=request.getAttribute("totalPage")%>&pageSize=5">末页</a>
<span>	</span>当前第<%=request.getAttribute("pageNow") %>页 总共<%=request.getAttribute("totalPage") %>页  共<%=request.getAttribute("totalRow") %>条数据
</td>
</tr>

<servlet>
<servlet-name>saleGoodsServlet</servlet-name>
<servlet-class>servlet.saleGoodsServlet</servlet-class>
</servlet>
<servlet>
<servlet-name>storeGoodsServlet</servlet-name>
<servlet-class>servlet.storeGoodsServlet</servlet-class>
</servlet>
<servlet-mapping>
<servlet-name>saleGoodsServlet</servlet-name>
<url-pattern>/saleGoodsList</url-pattern>
</servlet-mapping>
<servlet-mapping>
<servlet-name>storeGoodsServlet</servlet-name>
<url-pattern>/storeGoodsList</url-pattern>
</servlet-mapping>

public void service(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
//设置接受字符类型
request.setCharacterEncoding("UTF-8");
//设置输出字符类型
response.setContentType("text/html;charset=UTF-8");
TaobaoClient client = new DefaultTaobaoClient(
"http://gw.api.tbsandbox.com/router/rest", "***",
"***");
String saleGoodsResult = TaobaoOpenApiDemo.saleGioodsGet(client);
List<Goods> saleGoodsList = TaobaoOpenApiDemo
.changeList(saleGoodsResult);
//当前页页码
Integer pageNow = Integer.parseInt(request.getParameter("pageNow"));
//每页显示条数
Integer pageSize = Integer.parseInt(request.getParameter("pageSize"));
//总数据数
Integer totalRow = saleGoodsList.size();
//总页数
Integer totalPage = totalRow % pageSize == 0 ? totalRow / pageSize : totalRow / pageSize + 1;
//调用Page中List分页方法
Page pm = new Page(saleGoodsList, pageSize);
List subList = pm.getObjects(pageNow);
request.setAttribute("subList", subList);
request.setAttribute("pageNow", pageNow);
request.setAttribute("totalRow", totalRow);
request.setAttribute("totalPage", totalPage);
//返回页面
RequestDispatcher rd = request.getRequestDispatcher("saleGoodsList.jsp");
rd.forward(request, response);
}