jsp分页技术

1、以下为分页类：

import java.io.Serializable;
import java.util.List;

import org.apache.commons.lang.builder.ToStringBuilder;
import org.apache.commons.lang.builder.ToStringStyle;

public class ResultFilter<T> implements Serializable{

private static final long serialVersionUID = 5472321653620726832L;

private final static int DEFAULT_NAVIGATOR_SIZE = 5;

//当前页
private int currentPage = 1;
//每页显示数量
private int pageSize = 5;

//总条数
private int totalCount;

private boolean havaNextPage;

private boolean havePrePage;

private int navigatorSize;

//存放查询结果用的list
private List<T> items;

public ResultFilter(){

}

public ResultFilter(int totalCount, int pageSize, int currentPage) {
this(totalCount, pageSize, currentPage, DEFAULT_NAVIGATOR_SIZE);
}

public ResultFilter(int totalCount, int pageSize, int currentPage,
int navigatorSize) {
this.totalCount = totalCount;
this.pageSize = pageSize;
this.currentPage = currentPage;
this.navigatorSize = navigatorSize;
}

public int getPageCount() {
int pageCount = 0;
if (pageSize != 0) {
pageCount = totalCount / pageSize;
if (totalCount % pageSize != 0)
pageCount++;
}

return pageCount;
}

public int getCurrentPage() {
currentPage = currentPage < getPageCount() ? currentPage :
getPageCount();
currentPage = currentPage < 1 ? 1 : currentPage;

return currentPage;
}

public int getPageSize() {
return pageSize;
}

public int getTotalCount() {
return totalCount;
}

public boolean isHaveNextPage() {
havaNextPage = false;
if ((getPageCount() > 1) && (getPageCount() > getCurrentPage()))
havaNextPage = true;
return havaNextPage;
}

public boolean isHavePrePage() {
havePrePage = false;
if ((getPageCount() > 1) && (currentPage > 1))
havePrePage = true;
return havePrePage;
}

private int getNavigatorIndex(boolean isBegin) {
int beginNavigatorIndex = getCurrentPage() - navigatorSize / 2;
int endNavigatorIndex = getCurrentPage() + navigatorSize / 2;
beginNavigatorIndex = beginNavigatorIndex < 1 ? 1 : beginNavigatorIndex;
endNavigatorIndex = endNavigatorIndex < getPageCount() ?
endNavigatorIndex :
getPageCount();
while ((endNavigatorIndex - beginNavigatorIndex) < navigatorSize &&
(beginNavigatorIndex != 1 || endNavigatorIndex != getPageCount())) {
if (beginNavigatorIndex > 1)
beginNavigatorIndex--;
else if (endNavigatorIndex < getPageCount())
endNavigatorIndex++;
}

if(isBegin)
return beginNavigatorIndex;
else
return endNavigatorIndex;
}

public int getBeginNavigatorIndex() {
return getNavigatorIndex(true);
}

public int getEndNavigatorIndex() {
return getNavigatorIndex(false);
}

public List<T> getItems() {
return items;
}

public void setItems(List<T> items) {
this.items = items;
}

public void setCurrentPage(int currentPage) {
this.currentPage = currentPage;
}

public void setPageSize(int pageSize) {
this.pageSize = pageSize;
}

public void setTotalCount(int totalCount) {
this.totalCount = totalCount;
}

@Override
public String toString() {
return ToStringBuilder.reflectionToString(this, ToStringStyle.MULTI_LINE_STYLE);
}

}

2、在spring的controller中调用分页类：

@RequestMapping(value="/xxxList") //xxxList.jsp对应的controller
public ModelAndView xxxList(@ModelAttribute ResultFilter<xxx> rf){
systemService.listServiceAll(rf); //调用步骤3 ，分页获取xxx对象
return new ModelAndView("路径/xxxList", "rf", rf); //此处跳转到步骤5所表示的网页，并传递分页参数rf，其中“路径/xxxList”

//表示对应的jsp网页，比如myBook/bookList表示myBook目录下的bookList.jsp
}

3、连操作数据库的service层 获取全部service
@Transactional(readOnly = false)
public void listServiceAll(ResultFilter<Services> rf){
int count=getServiceList().size();
rf.setTotalCount(count);
rf.setItems(serviceDao.getListForPage("from Services", (rf.getCurrentPage() - 1 )* rf.getPageSize(), rf.getPageSize()));

//调用步骤4，分页查询数据库
}

4、

// -------------- 分页QL Query --------------//

@SuppressWarnings("unchecked")
public List<T> getListForPage(String hql,int begin,int num){
Query query = getSession().createQuery(hql);

return query.setFirstResult(begin).setMaxResults(num).list();

}

5、路径/xxxList 对应的jsp网页（注意第四行）

<%@ page language="java" contentType="text/html; charset=utf-8"
pageEncoding="utf-8"%>
<%@ include file="/WEB-INF/views/include/taglib.jsp"%>
<%@ taglib uri="my-taglib" prefix="my"%> <!--使用了自定义标签，该标签在步骤6中定义-->

<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
<title>XXXList</title>
</head>
<body>

<form>
<table id="contentTable" >
<tbody>
<c:url value="/xxxDetail" var="url1"></c:url>
<c:url value="/xxxList" var="url1"></c:url> <!--该jsp对应的controller-->
<tr><c:forEach items="${rf.items}" var="xxx">
<td valign="top" style="width:229px;oveflow:hidden;">

<table>
<tr><td ><a name="click to check the detail" href="${url1}?xxxId=${xxx.id}"><img src="${ctxStatic}/images/123.jpg"></img></a></td></tr>
<tr><td >${xxx.attribute1}</td></tr>
<tr><td >${xxx.attribute2}</td></tr>
</table>
</td>
</c:forEach>
</tr>
</tbody>
</table>
<div style="padding-top:30px;"></div>
<my:paging curr="${rf.currentPage}" total="${rf.pageCount}" size="${rf.pageSize}" href="${url2}"/> <!--使用了自定义标签-->
</form>
</body>
</html>

6、自定义标签‘my’

<?xml version="1.0" encoding="UTF-8"?>
<taglib xmlns="http://java.sun.com/xml/ns/j2ee"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://java.sun.com/xml/ns/j2ee http://java.sun.com/xml/ns/j2ee/web-jsptaglibrary_2_0.xsd" version="2.0">

<description>My Tag Library</description>
<tlib-version>1.0</tlib-version>
<short-name>my</short-name>
<uri>my-taglib</uri>

<tag>
<description>split page</description>
<name>paging</name>
<tag-class>aaa.bbb.ccc.PagingTag</tag-class> <!--用到了步骤7中的PagingTag类 ，aaa.bbb.ccc是PagingTag的路径-->
<body-content>empty</body-content>
<attribute>
<description>base href</description>
<name>href</name>
<required>false</required>
<rtexprvalue>true</rtexprvalue>
</attribute>
<attribute>
<description>curr page</description>
<name>curr</name>
<required>true</required>
<rtexprvalue>true</rtexprvalue>
</attribute>
<attribute>
<description>page size</description>
<name>size</name>
<required>true</required>
<rtexprvalue>true</rtexprvalue>
</attribute>
<attribute>
<description>total page</description>
<name>total</name>
<required>true</required>
<rtexprvalue>true</rtexprvalue>
</attribute>
<attribute>
<description>curr parameter name</description>
<name>cparam</name>
<required>false</required>
<rtexprvalue>false</rtexprvalue>
</attribute>
<attribute>
<description>page size parameter name</description>
<name>sparam</name>
<required>false</required>
<rtexprvalue>false</rtexprvalue>
</attribute>
<dynamic-attributes>false</dynamic-attributes>
</tag>

<tag>
<description>front split page</description>
<name>frontPaging</name>
<tag-class>com.aspire.cms.demo.framework.tag.FrontPagingTag</tag-class>
<body-content>empty</body-content>
<attribute>
<description>base href</description>
<name>href</name>
<required>false</required>
<rtexprvalue>true</rtexprvalue>
</attribute>
<attribute>
<description>result filter</description>
<name>rf</name>
<required>true</required>
<rtexprvalue>true</rtexprvalue>
</attribute>
<dynamic-attributes>false</dynamic-attributes>
</tag>

</taglib>

7、自定义标签类

package aaa.bbb.ccc;

import java.io.IOException;

import javax.servlet.jsp.JspException;
import javax.servlet.jsp.JspWriter;
import javax.servlet.jsp.tagext.SimpleTagSupport;

import org.apache.commons.lang.StringUtils;

public class PagingTag extends SimpleTagSupport {

private String href;

//当前页
private String cparam;
//每页条数
private String sparam;

private int curr;//当前页

private int size;//每页条数

private int total;//总页数

@Override
public void doTag() throws JspException, IOException {
JspWriter out = getJspContext().getOut();

if(StringUtils.isEmpty(cparam)) {
cparam = "currentPage";
}
if(StringUtils.isEmpty(sparam)) {
sparam = "pageSize";
}

if(!href.endsWith("?") && !href.endsWith("&")) {
if(href.indexOf("?") == -1) {
href = href + "?";
} else {
href = href + "&";
}
}

if (curr <= 0) {
curr = 1;
} else if (curr > total) {
curr = total;
}

out.append("<span>");
// 首页
if (curr == 1) {
out.append("首页");
} else {
href(out, href, 1, "首页");
}
out.append(" | ");
// 上一页
if (curr == 1) {
out.append("上一页");
} else {
href(out, href, curr - 1, "上一页");
}
out.append(" | ");
// 下一页
if (curr == total) {
out.append("下一页");
} else {
href(out, href, curr + 1, "下一页");
}
out.append(" | ");
// 末页
if (curr == total) {
out.append("末页");
} else {
href(out, href, total, "末页");
}
out.append("</span>");
out.append("<span>第");
out.append(curr + "/" + total);
out.append("页</span>");

super.doTag();
}

private void href(JspWriter out, String href, int curr, String title) throws IOException {
out.append("<a href=\"").append(href).append(cparam).append("=").append("" + curr).append("&").append(sparam).append("=").append("" + size).append("\">").append(title).append("</a>");
}

public int getCurr() {
return curr;
}

public void setCurr(int curr) {
this.curr = curr;
}

public int getTotal() {
return total;
}

public void setTotal(int total) {
this.total = total;
}

public String getHref() {
return href;
}

public void setHref(String href) {
this.href = href;
}

public String getCparam() {
return cparam;
}

public void setCparam(String cparam) {
this.cparam = cparam;
}

public String getSparam() {
return sparam;
}

public void setSparam(String sparam) {
this.sparam = sparam;
}

public int getSize() {
return size;
}

public void setSize(int size) {
this.size = size;
}

}