loadfile.java

一个jsp上传文件的servlet程序

import java.io.*;
import java.net.*;
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 LoadFile extends HttpServlet {
	  public void doPost( HttpServletRequest request, HttpServletResponse response )
	  throws ServletException, IOException
	  {
		  HttpSession session = request.getSession();
		  String tempName=(String)session.getId();
		  
		  File dir=new File("E:/work/UpLoadAndDownd","File");
		  if(!dir.exists())
		  {
		     dir.mkdir();
		  }
		  
		  File fp=null;
		  int n;
		  FileOutputStream out=null;
		  InputStream in=request.getInputStream();
		  if(dir.exists())
		  {
		  fp=new File("E:/work/UpLoadAndDownd/File",tempName);
		  out=new FileOutputStream(fp);
		  byte b[]=new byte[1000];
		  while((n=in.read(b))!=-1)
		  {
			  out.write(b,0,n);
		  }
		  }
		  else
		  {
			  response.sendRedirect("error.jsp");
		  }
		  
		in.close();
		out.close();

		
		RandomAccessFile ranFile=new RandomAccessFile(fp,"r");
		int getSecondLine=1;
		String secondLine="";
		String fileName="";
		while(getSecondLine<=2)
		{
			secondLine=ranFile.readLine();
			getSecondLine++;
			System.out.println(secondLine);
		}
		
		int position=secondLine.lastIndexOf('\\');
		fileName=secondLine.substring(position+1,secondLine.length()-1);
		//System.out.println(fileName);
		
		ranFile.seek(0);
		long forthEndPosition=0;
		int forth=1;
		int nn=0;
		while((nn=ranFile.readByte())!=-1&&(forth<=4))
		{
			if(nn=='\n')
			{
				forthEndPosition=ranFile.getFilePointer();
				forth++;
			}
		}
		
		byte cc[]=fileName.getBytes("ISO-8859-1");
		fileName=new String(cc);
		File f2=new File("E:/work/UpLoadAndDownd/File",fileName);
		RandomAccessFile ranFile2=new RandomAccessFile(f2,"rw");
		
		ranFile.seek(ranFile.length());
		long endPosition=ranFile.getFilePointer();
		//System.out.println("The Position 1 is:"+endPosition);
		long temp=endPosition;
		int j=1;
		while(temp>=0&&j<=6)
		{
			temp--;
			ranFile.seek(temp);
			nn=ranFile.readByte();
			if(nn=='\n')
			{
				endPosition=ranFile.getFilePointer();
				j++;
			}
			
		}
		//System.out.println("The Position 2 is:"+endPosition);
		//System.out.println("The File End Position is:"+ranFile.length());
		ranFile.seek(forthEndPosition);
		long startPosition=ranFile.getFilePointer();
		
		//System.out.println();
		while(startPosition<endPosition)
		{
			//System.out.println("The Position 3 is:"+endPosition);
			nn=ranFile.readByte();
			ranFile2.write(nn);
			startPosition=ranFile.getFilePointer();
		}
		ranFile.close();
		ranFile2.close();
		fp.delete();
	  }

}