jsp页面显示分页
pagebean.java
public class PageBean {
private int page = 1;// 页码
private int rows = 10;// 页大小
private int total = 0;// 总记录数
private boolean pagination = true;// 是否分页
private Map<String,String[]> paMap=new HashMap<>();
private String url;
public void setRequest(HttpServletRequest req) {
//保存上一次请求所携带得参数
this.setPaMap(req.getParameterMap());
this.setUrl(req.getRequestURI().toString());
//在jsp页面来控制是否分页
this.setPagination(req.getParameter("pagination"));
//在jsp页面控制一页展示多少条数据
this.setRows(req.getParameter("rows"));
this.setPage(req.getParameter("page"));
}
public void setPage(String page) {
this.page=StringUtils.isNotBlank(page)?Integer.valueOf(page):this.page;
}
public void setPagination(String pagination) {
this.pagination=StringUtils.isNotBlank(pagination)?!"false".equals(pagination):this.pagination;
}
public void setRows(String rows) {
this.rows=StringUtils.isNotBlank(rows)?Integer.valueOf(rows):this.rows;
}
public Map<String, String[]> getPaMap() {
return paMap;
}
public void setPaMap(Map<String, String[]> paMap) {
this.paMap = paMap;
}
public String getUrl() {
return url;
}
public void setUrl(String url) {
this.url = url;
}
public PageBean() {
super();
}
public int getPage() {
return page;
}
public void setPage(int page) {
this.page = page;
}
public int getRows() {
return rows;
}
public void setRows(int rows) {
this.rows = rows;
}
public int getTotal() {
return total;
}
public void setTotal(int 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;
}
/**
* 获得起始记录的下标
*
* @return
*/
public int getStartIndex() {
return (this.page - 1) * this.rows;
}
@Override
public String toString() {
return "PageBean [page=" + page + ", rows=" + rows + ", total=" + total + ", pagination=" + pagination + "]";
}
/**
* 获取最大的页码数
* @return
*/
public int getMaxPage() {
return this.total%this.rows==0 ? this.total/this.rows : this.total/this.rows+1;
}
/**
* 获取下一页
* @return
*/
public int getNextPage() {
return this.page < this.getMaxPage() ? this.page+1:this.page;
}
/**
* 获取上一页
* @return
*/
public int getpreviousPage() {
return this.page>1 ? this.page-1:this.page;
}
}
bookServlet.java
package com.web;
import java.io.IOException;
import java.sql.SQLException;
import java.util.List;
import java.util.Map;
import javax.jws.WebService;
import javax.servlet.ServletException;
import javax.servlet.annotation.WebFilter;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import com.entity.Book;
import com.jt.dao.BookDao;
import com.util.PageBean;
@WebServlet("/bookServlet ")
public class BookServlet extends HttpServlet {
private static final long serialVersionUID = 6304839939800249916L;
private BookDao bookDao=new BookDao();
@Override
protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
// TODO Auto-generated method stub
doPost(req, resp);
}
@Override
protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
// TODO Auto-generated method stub
String bname=req.getParameter("bname");
Book book=new Book();
book.setBname(bname);
// Map<String,String[]> parameterMap=req.getParameterMap();
// StringBuffer url= req.getRequestURL();
PageBean pageBean=new PageBean();
try {
pageBean.setRequest(req);
List<Book> list= this.bookDao.list(book, pageBean);
req.setAttribute("bookList", list);
req.setAttribute("pageBean",pageBean);
req.getRequestDispatcher("/BookList.jsp").forward(req, resp);
} catch (InstantiationException | IllegalAccessException | SQLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
}
过滤器：EncodingFiter.java
package com.util;
import java.io.IOException;
import java.util.Iterator;
import java.util.Map;
import java.util.Set;
import javax.servlet.Filter;
import javax.servlet.FilterChain;
import javax.servlet.FilterConfig;
import javax.servlet.ServletException;
import javax.servlet.ServletRequest;
import javax.servlet.ServletResponse;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
/**
* 中文乱码处理
*
*/
public class EncodingFiter implements Filter {
private String encoding = "UTF-8";// 默认字符集
public EncodingFiter() {
super();
}
public void destroy() {
}
public void doFilter(ServletRequest request, ServletResponse response,
FilterChain chain) throws IOException, ServletException {
HttpServletRequest req = (HttpServletRequest) request;
HttpServletResponse res = (HttpServletResponse) response;
// 中文处理必须放到 chain.doFilter(request, response)方法前面
res.setContentType("text/html;charset=" + this.encoding);
if (req.getMethod().equalsIgnoreCase("post")) {
req.setCharacterEncoding(this.encoding);
} else {
Map map = req.getParameterMap();// 保存所有参数名=参数值(数组)的Map集合
Set set = map.keySet();// 取出所有参数名
Iterator it = set.iterator();
while (it.hasNext()) {
String name = (String) it.next();
String[] values = (String[]) map.get(name);// 取出参数值[注：参数值为一个数组]
for (int i = 0; i < values.length; i++) {
values[i] = new String(values[i].getBytes("ISO-8859-1"),
this.encoding);
}
}
}
chain.doFilter(request, response);
}
public void init(FilterConfig filterConfig) throws ServletException {
String s = filterConfig.getInitParameter("encoding");// 读取web.xml文件中配置的字符集
if (null != s && !s.trim().equals("")) {
this.encoding = s.trim();
}
}
}
自定义标签类：PageTag.java
package com.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.util.PageBean;
public class PageTag extends BodyTagSupport {
private static final long serialVersionUID = -553969530960334073L;
private PageBean pageBean;
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.print(toHTML());
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
return super.doStartTag();
}
private String toHTML() {
// TODO Auto-generated method stub
StringBuilder sb=new StringBuilder();
//拼接下一次发送请求所要提交得隐藏得form表单
sb.append("<form id='pageBeanForm' action='"+pageBean.getUrl()+"' method='post'>");
sb.append(" <input type='hidden' name='page'>");
Map<String, String[]> paMap = pageBean.getPaMap();
if(paMap!=null&&paMap.size()>0) {
Set<Entry<String, String[]>> entrySet = paMap.entrySet();
for (Entry<String, String[]> entry : entrySet) {
//上一次请求可能携带页码naempage得参数，但是改参数在前面以及单独赋值
//为什么要单独赋值？因为上一次请求时第一页得数据，下一次可能时第二页，以后这前后请求page对应得值不一样，需要单独赋值
if(!"page".equals(entry.getKey())) {
// <input type='hidden' name='hobby' value='1'>
// <input type='hidden' name='hobby' value='2'>
//[1,2]
for(String val:entry.getValue()) {
sb.append("<input type='hidden' name='"+entry.getKey()+"' value='"+val+"'>");
}
}
}
}
sb.append("</form>");
//拼接分页条
sb.append("<div style='text-align: right; font-size: 12px;'>");
sb.append("每页"+pageBean.getRows()+"条，共"+pageBean.getTotal()+"条，第"+pageBean.getPage()+"页，共"+pageBean.getMaxPage()+"页 <a ");
sb.append(" href='javascript:gotoPage(1)'>首页</a> <a");
sb.append(" href='javascript:gotoPage("+pageBean.getpreviousPage()+")'>上一页</a> <a");
sb.append(" href='javascript:gotoPage("+pageBean.getNextPage()+")'>下一页</a> <a");
sb.append(" href='javascript:gotoPage("+pageBean.getMaxPage()+")'>尾页</a> <input type='text'");
sb.append(" id='skipPage'");
sb.append(" style='text-align: center; font-size: 12px; width: 50px;'> <a");
sb.append(" href='javascript:skipPage()'>Go</a>");
sb.append("</div>");
//拼接分页所需要得js代码
sb.append("<script type='text/javascript'> ");
sb.append("function gotoPage(page) {");
sb.append("document.getElementById('pageBeanForm').page.value = page;");
sb.append("document.getElementById('pageBeanForm').submit();");
sb.append("}");
sb.append("function skipPage() {");
sb.append("var page = document.getElementById('skipPage').value;");
sb.append("if(!page || isNaN(page) || parseInt(page)<1 || parseInt(page)>"+pageBean.getMaxPage()+"){");
sb.append("alert('请输入1~N的数字');");
sb.append("return;");
sb.append("}");
sb.append("gotoPage(page);");
sb.append("}");
sb.append("</script>");
return sb.toString();
}
}
jsp页面：bookList.jsp
<%@ 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="/jt" %>
<!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>Insert title here</title>
</head>
<body>
<h2>小说目录</h2>
<br>
<form action="${pageContext.request.contextPath}/bookServlet"
method="post">
书名：<input type="text" name="bname"> <input type="submit"
value="确定">
</form>
<table border="1" width="100%">
<tr>
<td>编号</td>
<td>名称</td>
<td>价格</td>
</tr>
<c:forEach items="${bookList }" var="b">
<tr>
<td>${b.bid }</td>
<td>${b.bname }</td>
<td>${b.price }</td>
</tr>
</c:forEach>
</table>
<z:page pageBean="${pageBean }"></z:page>
</body>
</html>
接下来就是运行结果：
（在这里我们可以跳转，首页尾页下一页上一页）
再接下来就是通用分页带给我们的好处演示啦
新建一个servlet跟jsp页面
servlet
package com.web;
import java.io.IOException;
import java.sql.SQLException;
import java.util.List;
import javax.servlet.ServletException;
import javax.servlet.annotation.WebFilter;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import com.entity.Blog;
import com.jt.dao.BlogDao;
import com.util.PageBean;
@WebServlet("/blogServlet")
public class BlogServlet extends HttpServlet {
private BlogDao blogDao=new BlogDao();
@Override
protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
// TODO Auto-generated method stub
doPost(req, resp);
}
@Override
protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
// TODO Auto-generated method stub
Blog blog=new Blog();
blog.setBookname(req.getParameter("bookname"));
PageBean pageBean=new PageBean();
try {
List<Blog> list = this.blogDao.list(blog, pageBean);
req.setAttribute("blogList",list);
req.setAttribute("pageBean",pageBean);
req.getRequestDispatcher("/BlogList.jsp").forward(req, resp);
} catch (InstantiationException | IllegalAccessException | SQLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
}
jsp页面
<%@ 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="/jt" %>
<!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>Insert title here</title>
</head>
<body>
<h2>小说目录</h2>
<br>
<form action="${pageContext.request.contextPath}/blogServlet"
method="post">
书名：<input type="text" name="bname"> <input type="submit"
value="确定">
</form>
<table border="1" width="100%">
<tr>
<td>编号</td>
<td>名称</td>
</tr>
<c:forEach items="${blogList }" var="b">
<tr>
<td>${b.id }</td>
<td>${b.bookname }</td>
</tr>
</c:forEach>
</table>
<z:page pageBean="${pageBean }"></z:page>
</body>
</html>
演示到这里就结束啦！！！
浙公网安备 33010602011771号