pageservlet.java

servlet的几个简单的例子

import java.io.IOException;
import java.io.PrintWriter;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;

import javax.servlet.ServletConfig;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;
 
public class PageServlet extends HttpServlet {
    Page page;
    private ResultSet rs = null;
    
    public PageServlet() {
        super();
    }
    public void init(ServletConfig config) throws ServletException{
        try {
            getRs();
        } catch (SQLException ex) {
            ex.printStackTrace();
        }
    }
    public void destroy() {
        super.destroy();
    }
    public void getRs() throws SQLException{
        Connection conn = null;
        Statement stat;
        String hostName = "localhost"; // 主机名或者IP地址
        String portNumber = "1433"; // 端口号，默认为1521
        String databaseSID = "student"; // SID名称
        String userName = "sa"; // 用户名
        String password = "sa"; // 用户密码
        String url = "jdbc:microsoft:sqlserver://" + hostName + ":" + portNumber + ";databaseName=" + databaseSID; // 连接字符串
        try {
            Class.forName("com.microsoft.jdbc.sqlserver.SQLServerDriver"); // 装载驱动程序
            conn = DriverManager.getConnection(url, userName, password); // 建立连接
        } catch (Exception e) {
            e.printStackTrace();
        }
        //stat = conn.createStatement();
        String actionStat = "select * from lesson ";
        stat   =   conn.createStatement(ResultSet.TYPE_SCROLL_INSENSITIVE, ResultSet.CONCUR_READ_ONLY);
        rs= stat.executeQuery(actionStat);
        page = new Page();
    }
    
    public void doGet(HttpServletRequest request, HttpServletResponse response)
    throws ServletException, IOException {
        try {
            getRs();
        } catch (SQLException ex) {
            ex.printStackTrace();
        } 
        HttpSession hsession = request.getSession();

        response.setContentType("text/html;charset=gbk");
        PrintWriter out = response.getWriter(); 
        if(hsession.getAttribute("userid")==null){
            out.println("<script language='javascript'>alert('未登陆')</script>");
            return;
        }
        int go ;
        if(request.getParameter("goto") == null){
            go = 1;
        } else {
            go = Integer.parseInt(request.getParameter("goto"));
        }
        try {
            page.setView(rs, "table",go,5);
            out.println(page.getView());
        } catch (Exception e) {
            e.printStackTrace();
            out.println(e.getMessage());
        }  
        out.flush();
        out.close();
    }
    
    public void doPost(HttpServletRequest request, HttpServletResponse response)
    throws ServletException, IOException {
        this.doGet(request, response);
    }
}