The method of realizing fast uploading files by JSP _jsp programming

This article describes the JSP implementation of fast upload file method. Share to everyone for your reference. Specifically as follows:

This demo JSP does not use the Third-party library, the realization of fast upload file function

1. Fileupload.java:

Package fileupload;
Import Java.io.BufferedOutputStream;
Import Java.io.File;
Import Java.io.FileOutputStream;
Import Javax.servlet.ServletInputStream;
  /** * *//** * @author qch * */public class FileUpload {ServletInputStream in=null;
  String fpath= "c://";
    Public FileUpload () {fpath= "c://";
  In=null;
  } public void Setinputstream (ServletInputStream in) {this.in=in;
  public void Setfpath (String p) {this.fpath=p;
  Public String Getfpath () {return fpath;
    public string GetParameter () {string r=null;
    try {r=getparameter (in);
    catch (Exception e) {e.printstacktrace ();
  } return R;
    Public long Getfileupload () {long r=-1;
    try {r=getfileupload (In,fpath);
    catch (Exception e) {e.printstacktrace ();
  } return R;
    The public String getparameter (ServletInputStream in)//can only be extracted in order throws Exception {int L = 0; Byte[] b = new byte[1024];
    L = in.readline (b, 0, b.length);/sequentially read the start of the property, the name, the type of the property value, the value of the property string si = new string (b); if (Si.startswith ("----------------------------")) {//means to start reading from the start character, or it should be a property after the file has just been read, you should read it less once L = In.readline (b, 0,
    B.length);
    L = in.readline (b, 0, b.length);
    L = in.readline (b, 0, b.length);
    String value = new String (b, 0, L);
  return value; Public long Getfileupload (ServletInputStream in, String Fpath)//need to provide input stream and storage path throws Exception {//OUT.PR
    INTLN ("File Information:<br>");
    Long begin = System.currenttimemillis ();//Transfer time timed start int l = 0;
    Byte[] B = new byte[1024];
    L = in.readline (b, 0, b.length);
    String sign = new String (b, 0, L);//eg.-----------------------------7d9dd29630a34 L = in.readline (b, 0, b.length); String info = new String (b, 0, L);//EG.
    Content-disposition:form-data;
    Name= "File";
    L = in.readline (b, 0, b.length); String type=new//String (b,0,l);//eg. Content-type:Application/octet-stream (program file) L = in.readline (b, 0, b.length);
    String Nulll=new string (b,0,l);//This value should be an empty int nindex = Info.tolowercase (). IndexOf ("filename=\");
    int nlastindex = Info.tolowercase (). IndexOf ("\", nindex + 10);
    String filepath = info.substring (nindex +, nlastindex);
    int na = Filepath.lastindexof ("\");
    String filename = filepath.substring (Na + 1);
    Out.println ("File absolute path:" +filepath+ "<br>");
    OUT.PRINTLN ("FileName:" +filename+ "<br><br>");
    String Path=fpath + filename;
    File Fi = Object file if (!fi.exists () &&!fi.createnewfile ()) return-2;
    Bufferedoutputstream f = new Bufferedoutputstream (new FileOutputStream (FI)); while ((L = in.readline (b, 0, b.length)) > 0) {if (L = = Sign.length ()) {String sign1 = new St
        Ring (b, 0, sign.length ());
        Out.println (sign1+ "<br>"); if (Sign1.startswith (sign))//compare to whether the file has passed the break;
      F.write (b, 0, L);
    F.flush ();
    } f.flush ();
    F.close ();
    Long end = System.currenttimemillis ()//delivery time timed over//out.println ("Upload file:" + (End-begin) + "millisecond <br>");
  return end-begin;

 }
}

2. submitfile.jsp:

<%@ page language= "java" import= "java.util.*" pageencoding= "GB18030"%> <% String Path = Request.getcontextpat
  H ();  String basepath = request.getscheme () + "://" + request.getservername () + ":" + request.getserverport () + path
+ "/"; %> <! DOCTYPE HTML PUBLIC "-//w3c//dtd HTML 4.01 transitional//en" >  

3. Answerfile.jsp:



<%@ page language= "java" import= "java.util.*,java.io.*" pageencoding= "GB18030"%> <% String Path = request.ge
  Tcontextpath ();  String basepath = request.getscheme () + "://" + request.getservername () + ":" + request.getserverport () + path
+ "/"; %> <! DOCTYPE HTML PUBLIC "-//w3c//dtd HTML 4.01 transitional//en" >  

I hope this article will help you with your JSP programming.