pageservlet.java

bs项目里分页,这里采用的是ajax滑动分页.

package book.slider;

import java.sql.*;
import java.util.Vector;
import javax.servlet.ServletException;
import javax.servlet.http.*;

public class pageServlet extends HttpServlet {
	
	public void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, java.io.IOException {
		
		//设置每页显示10条记录
		int PAGE_SIZE = 10;
		//获得请求中page的值
		String currPage = request.getParameter("page") != null ? request.getParameter("page") : "";
		System.out.println("aa=" + currPage + "=aa");
		if(!currPage.equals("")){
			int number = 1;
			try {
				number = Integer.parseInt(currPage);//将String转化为int型
			} catch (Exception e) {
				number = 1;
			}
			//查询所有记录的sql语句
			String sql = "select * from student";
			//执行查询返回记录集对象
			ResultSet rs = DbManager.getResultSet(sql);
			//定义保存数据的向量
			Vector vData = new Vector();
			System.out.println("bb=" + number + "=bb");
			try {
				//将游标移动到当前页的第一条记录上
				rs.absolute((number - 1) * PAGE_SIZE + 1);
				//定义Student实体类
				StudentEO student = null;
				int i = 0;
				//循环记录集,将记录集中的数据保存到实体类中
				while(i < PAGE_SIZE) {
					student = new StudentEO();
					student.setId(rs.getInt("STUDENT_ID"));
					student.setStudentName(rs.getString("STUDENT_NAME"));
					student.setStudentClass(rs.getString("STUDENT_CLASS"));
					//将保存数据后的student实体类保存到向量中
					vData.add(student);
					rs.next();
					i ++;
				}
				//最后释放Connection对象
				DbManager.releaseConnection();
			} catch (SQLException e) {
				e.printStackTrace();
			}
			//设置返回数据为xml格式
			response.setContentType("text/xml");
			java.io.PrintWriter out = response.getWriter();
			//调用parasToXML方法组织XML数据
			out.print(parasToXML(vData));
		}else{
			response.setContentType("text/html");
			java.io.PrintWriter out = response.getWriter();
			String sqlCount = "select count(*) as c from student";
			int count = DbManager.getCount(sqlCount);
			if(count % PAGE_SIZE != 0)
				count = count / PAGE_SIZE + 1;
			else
				count = count / PAGE_SIZE;
			out.print(count);
		}
	}

	public void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, java.io.IOException {

		doPost(request, response);
	}

	public String parasToXML(Vector v) {
		
		StringBuffer buf = new StringBuffer();
		//将向量中的数据组织成XML数据
		buf.append("<?xml version=\"1.0\" encoding=\"UTF-8\"?>");
		buf.append("<students>");
		for (int i = 0; i < v.size(); i ++) {
			StudentEO s = (StudentEO) v.get(i);
			buf.append("<student>");
			buf.append("<id>" + s.getId() + "</id>");
			buf.append("<name>" + s.getStudentName() + "</name>");
			buf.append("<class>" + s.getStudentClass() + "</class>");
			buf.append("</student>");
		}
		buf.append("</students>");
		return buf.toString();
	}
}