通用分页（二）
通用分页二
接着昨天的来
完整的pageBean
jsp界面
PageTag
action包
package com.tang.action;
import java.io.IOException;
import java.util.List;
import java.util.Map;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;
import com.tang.biz.ICompanyBiz;
import com.tang.biz.impl.CompanyBiz;
import com.tang.entity.Company;
import com.tang.util.PageBean;
public class CompanyServlet extends HttpServlet {
@Override
protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
doPost(req, resp);
}
@Override
protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
//1.设置编码
req.setCharacterEncoding("utf-8");
HttpSession session = req.getSession();
//2.获取页面传过来的值
String job = req.getParameter("job");
System.out.println(req.getContextPath());
System.out.println(req.getServletPath());
System.out.println(req.getRequestURI());
//Map parameterMap = req.getParameterMap();
PageBean pageBean = new PageBean();
pageBean.setRequest(req);
Company company = new Company();
company.setJob(job);
//3.调用biz层查询
ICompanyBiz icb = new CompanyBiz();
List listCompany = icb.listCompany(company, pageBean);
// try {
// listBook = bookBiz.listBook(book,pageBean);
// } catch (Exception e) {
// throw new RuntimeException();
// }
//4.将查询出的集合放到session作用域中
session.setAttribute("listCompany", listCompany);
session.setAttribute("pageBean", pageBean);
req.getRequestDispatcher("listCompany.jsp").forward(req, resp);
}
}
把CompanyServlet类，还有EncodingFilter类进行配置，不然运行出错
web.xml
J2EE_paging
index.html
index.htm
index.jsp
default.html
default.htm
default.jsp
EncodingFilter
com.tang.util.EncodingFiter
EncodingFilter
/*
CompanyServlet
com.tang.action.CompanyServlet
CompanyServlet
/listCompany.action
pageBean
package com.tang.util;
import java.util.Map;
import javax.servlet.http.HttpServletRequest;
public class PageBean {
private Integer page =1; //页码
private Integer rows =10; //页大小
private Integer total=0; //总记录数
private boolean pagination=true; //默认 false不分页
private String url;//请求地址
private Map map;//请求参数集合
public PageBean() {
super();
}
public Integer getPage() {
return page;
}
public void setPage(Integer page) {
this.page = page;
}
public void setPage(String page) {
if(page!=null && !"".equals(page)) {
this.page = Integer.parseInt(page);
}
}
public Integer getRows() {
return rows;
}
public void setRows(Integer rows) {
this.rows = rows;
}
public void setRows(String rows) {
if(rows!=null && !"".equals(rows)) {
this.rows = Integer.parseInt(rows);
}
}
public Integer getTotal() {
return total;
}
public void setTotal(Integer total) {
this.total = total;
}
public void setTotal(String total) {
this.total = Integer.parseInt(total);
}
public boolean isPagination() {
return pagination;
}
public void setPagination(boolean pagination) {
this.pagination = pagination;
}
public void setPagination(String pagination) {
if(pagination!=null && !"".equals(pagination)) {
this.pagination = Boolean.parseBoolean(pagination);
}
}
public String getUrl() {
return url;
}
public void setUrl(String url) {
this.url = url;
}
public Map getMap() {
return map;
}
public void setMap(Map map) {
this.map = map;
}
@Override
public String toString() {
return "PageBean [page=" + page + ", rows=" + rows + ", total=" + total + ", pagination=" + pagination + "]";
}
public int getStartIndex() {
return (this.page-1)*this.rows;
}
/**
* 对pageBean初始化
* @param req
*/
public void setRequest(HttpServletRequest req) {
String page = req.getParameter("page");//页码
String rows = req.getParameter("rows");//页大小
String pagination = req.getParameter("pagination");//是否分页
this.setPage(page);
this.setRows(rows);
this.setPagination(pagination);
this.setUrl(req.getRequestURI());
this.setMap(req.getParameterMap());
}
/**
* 得到上一页的页码
* @return
*/
public int getPerPage() {
int perPage = this.page-1;
if(perPage<1) {
perPage = 1;
}
return perPage;
}
/**
* 得到下一页的页码
* @return
*/
public int getNextPage() {
int nextPage = this.page+1;
if(nextPage>getMaxPage()) {
nextPage = getMaxPage();
}
return nextPage;
}
/**
* 得到最大的页码
* @return
*/
public int getMaxPage() {
int maxPage = this.total / this.rows;
if(this.total % this.rows != 0) {
maxPage ++;
}
return maxPage;
}
}
pageTag（是把jsp界面中的一些代码包装起来，整理在一起）
package com.tang.tag;
import java.io.IOException;
import java.util.Map;
import java.util.Map.Entry;
import java.util.Set;
import javax.servlet.jsp.JspException;
import javax.servlet.jsp.JspWriter;
import javax.servlet.jsp.tagext.BodyTagSupport;
import com.tang.util.PageBean;
public class PageTag extends BodyTagSupport {
private PageBean pageBean;
public PageTag() {
super();
}
public PageBean getPageBean() {
return pageBean;
}
public void setPageBean(PageBean pageBean) {
this.pageBean = pageBean;
}
@Override
public int doStartTag() throws JspException {
JspWriter out = pageContext.getOut();
try {
out.println(toHtml());
} catch (Exception e) {
throw new RuntimeException(e);
}
return super.doStartTag();
}
private String toHtml() {
//pageBean为空或者 不分页
if(null==pageBean || !pageBean.isPagination()) {
return "";
}
StringBuilder sb = new StringBuilder();
//拼接form表单
/**/
sb.append("");
//拼接div部分
/**/
sb.append("");
sb.append("第"+pageBean.getPage()+"页/总共"+pageBean.getMaxPage()+"页,共"+pageBean.getTotal()+"条记录 ");
//首页 上一页
if(pageBean.getPage()!=1) {
sb.append("首页 \r\n" +
" 上一页 ");
}else {
sb.append("首页 上一页 ");
}
//末页 下一页
if(pageBean.getPage()!=pageBean.getMaxPage()) {
sb.append("下一页 \r\n" +
" 末页 ");
}else {
sb.append("下一页 末页 ");
}
//跳转页
sb.append(" ");
sb.append("GO");
sb.append("");
//拼接js
/**/
sb.append("");
return sb.toString();
}
}
在写一个自定义标签，把pageTag配置到z.tld中
1.0
1.2
l
/zking
page
com.tang.tag.PageTag
empty
pageBean
true
true
jsp界面
<%@ page language="java" contentType="text/html; charset=UTF-8"
pageEncoding="UTF-8"%>
<%@taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core" %>
<%@taglib prefix="z" uri="/zking" %>
公司信息
公司信息
序号
职位
公司
工作地址
薪资
学历要求
爬取时间
常有详情
${s.count }
${c.job }
${c.company }
${c.address }
${c.salary }
${c.limit }
${c.time }
常有详情
<%--
--%>
界面
查询所有：
模糊查询，查询工程，查出有两页，13条记录：
第一页：
第二页：
