awardsvlt.java

采用基于B/S结构进行开发学生管理信息系统,本系统采用Servlet+Jsp+JavaBean+MySQL 的设计方式

import java.io.*;
import java.sql.*;
import javax.servlet.*;
import javax.servlet.http.*;
import myBean.AwardPC;

public class AwardSvlt extends HttpServlet{
	
public void doGet(HttpServletRequest req, HttpServletResponse res)
    throws ServletException, IOException {
    String stu_id = req.getParameter("stu_id");
    int success = 0;
    String action = req.getParameter("action");
    AwardPC ad = null;
    String message="";
    String record_time = req.getParameter("record_time");
    String levels = req.getParameter("levels"); 
   	
   if("new".equalsIgnoreCase(action)){
  	  if(isTrue(req,res,stu_id,record_time,levels) && hasLogin(req,res,stu_id,record_time,levels)){
         ad = doNew(req,res,stu_id,record_time,levels);      
         sendBean(req, res, ad, "/getAward.jsp");
        }
    }  
    
    if ("update".equalsIgnoreCase(action)){
    	//levels = req.getParameter("description");      	 	
      if(isTrue(req,res,stu_id,record_time,levels)){
    	   try{		
     	       ad = doUpdate(req,res,stu_id,record_time,levels);
     	       sendBean(req,res,ad,"/getAward.jsp");
            }
     	   catch(SQLException e){} 
     	  }
    }
			   
    if ("delete".equalsIgnoreCase(action)) {
    	levels = req.getParameter("code");
    	try{			
      	success = doDelete(req,res,stu_id,record_time,levels);	
      	    }
      	    catch(SQLException e){}				
    	if (success == 0) {
    		doError(req, res, "无效操作，删除失败！ " );
    	} else {
    		res.sendRedirect("http://localhost:8080/0903/getAward.jsp");
    	}   
    }
    }
    

 public AwardPC doNew(HttpServletRequest req,HttpServletResponse res,String stu_id,String record_time,String levels)
                           throws ServletException,IOException{
                           
      AwardPC ad= new AwardPC();                 	
      String info = new String(req.getParameter("info").getBytes("ISO8859_1"));
      String validate = new String(req.getParameter("validate").getBytes("ISO8859_1"));
      
      ad.setStu_id(stu_id);
      ad.setLevels(levels);
      ad.setRecord_time(record_time);
      ad.setInfo(info);
      ad.setValidate(validate);     
      ad.addAwardPC(); 
   
      return ad;                	           	
 	}

 public AwardPC doUpdate(HttpServletRequest req,HttpServletResponse res ,String stu_id,String record_time,String levels)
                           throws ServletException,IOException,SQLException {                            	                     	
    AwardPC ad = new AwardPC();                
    String info = req.getParameter("info");
    String validate = new String(req.getParameter("validate").getBytes("ISO8859_1"));
    ad.setStu_id(stu_id);
    ad.setRecord_time(record_time);
    ad.setLevels(levels);
    ad.setInfo(info);
    ad.setValidate(validate);
    
    ad.updateAwardPC();
		return ad;
  }

  public int doDelete(HttpServletRequest req,HttpServletResponse res,String stu_id,String record_time,String levels) 
                   throws ServletException,SQLException,IOException {
  	int num=0;
    AwardPC ad=new AwardPC();
    num=ad.deleteAwardPC(stu_id,record_time,levels);
    return num;
  }
	
public void sendBean(HttpServletRequest req, HttpServletResponse res,
                       AwardPC ad, String target)
                       throws ServletException, IOException {
    req.setAttribute("ad", ad);
    RequestDispatcher rd = getServletContext().getRequestDispatcher(target);
    rd.forward(req, res);
  }
  
  
  public void doError(HttpServletRequest req,
                      HttpServletResponse res,
                      String str)
                      throws ServletException, IOException {


    req.setAttribute("problem", str);
    RequestDispatcher rd = getServletContext().getRequestDispatcher("/errorpage.jsp");
    rd.forward(req, res);
  }
  
  public boolean hasLogin(HttpServletRequest req, HttpServletResponse res,String stu_id,String record_time,String levels)
                   throws ServletException, IOException{
  	boolean f=true;
  	String message="对不起，该项已经存在了!";
  	AwardPC ad= new AwardPC();
  	f= ad.hasLogin(stu_id,record_time,levels);
  	if(f==false){
  	   doError(req,res,message);	
  		}
  		return f;
  	}
  
  public boolean isTrue(HttpServletRequest req, HttpServletResponse res,
                        String stu_id,String record_time,String levels)
                        throws ServletException, IOException {
   boolean f=true;                     	
   String message ="";
   if(stu_id==null || stu_id.trim().equals("")){
   	  f=false;
   	  message="错误，学号不能为空！";
   	 doError(req,res,message);	
   }else if(levels==null || levels.trim().equals("")){
   	 f=false;
   	 message="错误，奖励不能为空！";
   	 doError(req,res,message);
   }
   else if(record_time==null || record_time.trim().equals("")){
   	 f=false;
   	 message="错误，日期必须输入！";
   	 doError(req,res,message);
  }  
     return f;     
  }
  
  public void doPost(HttpServletRequest req, HttpServletResponse res)
    throws ServletException, IOException {

    doGet(req, res);

  }
	
	
}