controllerservlet.java

包含了很多JAVA的例子,适合初学者用来参考一下,谢谢支持.

package myServlet;

import javax.servlet.*;
import javax.servlet.http.*;
import java.io.*;
import java.util.*;
import java.sql.*;
import myBean.PersonBean;

public class ControllerServlet extends HttpServlet {
    private static final String CONTENT_TYPE = "text/html; charset=GB2312";
    //public synchronized void service(ServletRequest request,ServletResponse response)
    //            throws java.io.IOException, ServletException{
    public void doGet(HttpServletRequest request, HttpServletResponse response) throws
            ServletException, IOException {
        response.setContentType(CONTENT_TYPE) ;
        request.setCharacterEncoding("GB2312");
        int minimumAge = 0;
        int maximumAge = 0;
        //获取请求参数minAge和maxAge
        String minimumAgeStr = request.getParameter("minAge");
        String maximumAgeStr = request.getParameter("maxAge");
        System.out.println("属性minimumAgeStr:"+minimumAgeStr);
        // 解析出错,转向错误处理页面BadAge.jsp
        try{
            minimumAge = Integer.parseInt(minimumAgeStr);
        }
        catch (Exception exc){
            gotoPage("/BadAge.jsp?reason=Invalid+minimum+age",
                request, response);
        }
        try{
            maximumAge = Integer.parseInt(maximumAgeStr);
        }
        catch (Exception exc){
            gotoPage("/BadAge.jsp?reason=Invalid+maximum+age",
                request, response);
            return;
        }
        //获取所有符合条件的人员
        PersonBean pb=new PersonBean();
        ResultSet rs = pb.query("SELECT * FROM persons where age >'"+minimumAge+
                       "' and age <='"+maximumAge+"'" + " order by age");
        int index=0;
        int rows=0;
        PersonBean pbs[]=null;
        try{
            if (rs.last())
                rows = rs.getRow();
            if (rows == 0)return;
            pbs = new PersonBean[rows];
            rs.first();
            do{
                pbs[index] = new PersonBean();
                pbs[index].setName(rs.getString("name"));
                pbs[index].setSex(rs.getString("sex"));
                pbs[index].setAge(rs.getInt("age"));
                pbs[index].setTel(rs.getString("tel"));
                System.out.println(""+pbs[index].getName());
                index++;
        	}while (rs.next());
        }catch(SQLException e){
            gotoPage("/BadAge.jsp?reason=Database+error",
                request, response);
            return;
        }

        System.out.println("将结果保存到属性people中,便于JSP访问:"+rows);

        // 将结果保存到属性people中,便于JSP访问
        request.setAttribute("people",pbs);
        //调用JSP视图页面输出结果
        gotoPage("/ShowPeople.jsp",request, response);
        return;
    }

    //gotoPage()方法处理页面转向的调度
    public void gotoPage(String pageName,ServletRequest request, ServletResponse response)
                throws IOException, ServletException {
        RequestDispatcher d = getServletContext().getRequestDispatcher(pageName);
        d.forward(request, response);
    }
}