import java.io.*;

import java.util.*;

import javax.servlet.*;

import javax.servlet.http.*;

public class Upload {

private String saveDir = "."; // 要保存文件的路徑

private String contentType = ""; // 文檔類型

private String charset = ""; // 字符集

private ArrayList tmpFileName = new

ArrayList(); // 臨時存放文件名的數據結構

private Hashtable parameter = new Hashtable();

// 存放參數名和值的數據結構

private ServletContext context; //

程序上下文,用于初始化

private HttpServletRequest request; //

用于傳入請求對象的實例

private String boundary = ""; // 內存數據的分隔符

private int len = 0; // 每次從內在中實際讀到的字節長度

private String queryString;

private int count; // 上載的文件總數

private String[] fileName; // 上載的文件名數組

private long maxFileSize = 1024 * 1024 * 10;

// 最大文件上載字節;

private String tagFileName = "";

public final void init(HttpServletRequest

request) throws ServletException {

this.request = request;

boundary =

request.getContentType().substring(30); // 得到內存中數據分界符

queryString =

request.getQueryString();

}

public String getParameter(String s) { //

用于得到指定字段的參數值,重寫request.getParameter(String

// s)

if (parameter.isEmpty())

{

return

null;

}

return (String)

parameter.get(s);

}

public String[] getParameterValues(String s) {

// 用于得到指定同名字段的參數數組,重寫request.getParameterValues(String

// s)

ArrayList al = new

ArrayList();

if (parameter.isEmpty())

{

return

null;

}

Enumeration e =

parameter.keys();

while (e.hasMoreElements())

{

String key =

(String) e.nextElement();

if (-1 !=

key.indexOf(s + "||||||||||") || key.equals(s)) {

al.add(parameter.get(key));

}

}

if (al.size() == 0) {

return

null;

}

String[] value = new

String[al.size()];

for (int i = 0; i

< value.length; i++) {

value[i] =

(String) al.get(i);

}

return value;

}

public String getQueryString() {

return queryString;

}

public int getCount() {

return count;

}

public String[] getFileName() {

return fileName;

}

public void setMaxFileSize(long size) {

maxFileSize = size;

}

public void setTagFileName(String filename)

{

tagFileName = filename;

}

public void setSaveDir(String saveDir) { //

設置上載文件要保存的路徑

this.saveDir = saveDir;

File testdir = new

File(saveDir); // 為了保證目錄存在,如果沒有則新建該目錄

if (!testdir.exists()) {

testdir.mkdirs();

}

}

public void setCharset(String charset) { //

設置字符集

this.charset = charset;

}

public boolean uploadFile() throws

ServletException, IOException { // 用戶調用的上載方法

setCharset(request.getCharacterEncoding());

return

uploadFile(request.getInputStream());

}

private boolean uploadFile(ServletInputStream

servletinputstream) throws // 取得央存數據的主方法

ServletException,

IOException {

String line = null;

byte[] buffer = new

byte[256];

while ((line = readLine(buffer,

servletinputstream, charset)) != null) {

if

(line.startsWith("Content-Disposition: form-data;")) {

int

i = line.indexOf("filename=");

if

(i >= 0) { //

如果一段分界符內的描述中有filename=,說明是文件的編碼內容

String

fName = getFileName(line);

if

(fName.equals("")) {

continue;

}

if

(count == 0 && tagFileName.length()

!= 0) {

String

ext = fName

.substring((fName.lastIndexOf(".")

+ 1));

fName

= tagFileName + "." + ext;

}

tmpFileName.add(fName);

count++;

while

((line = readLine(buffer, servletinputstream, charset)) != null)

{

if

(line.length() <= 2) {

break;

}

}

File

f = new File(saveDir, fName);

FileOutputStream

dos = new FileOutputStream(f);

long

size = 0l;

while

((line = readLine(buffer, servletinputstream, null)) != null)

{

if

(line.indexOf(boundary) != -1) {

break;

}

size

+= len;

if

(size > maxFileSize) {

throw

new IOException("文件超過" + maxFileSize + "字節!");

}

dos.write(buffer,

0, len);

}

dos.close();

}

else { // 否則是字段編碼的內容

String

key = getKey(line);

String

value = "";

while

((line = readLine(buffer, servletinputstream, charset)) != null)

{

if

(line.length() <= 2) {

break;

}

}

while

((line = readLine(buffer, servletinputstream, charset)) != null)

{

if

(line.indexOf(boundary) != -1) {

break;

}

value

+= line;

}

put(key,

value.trim(), parameter);

}

}

}

if (queryString != null)

{

String[] each

= split(queryString, "&");

for (int k =

0; k < each.length; k++) {

String[]

nv = split(each[k], "=");

if

(nv.length == 2) {

put(nv[0],

nv[1], parameter);

}

}

}

fileName = new

String[tmpFileName.size()];

for (int k = 0; k

< fileName.length; k++) {

fileName[k] =

(String) tmpFileName.get(k); // 把ArrayList中臨時文件名倒入數據中供用戶調用

}

if (fileName.length == 0)

{

return false;

// 如果fileName數據為空說明沒有上載任何文件

}

return true;

}

private void put(String key, String value,

Hashtable ht) {

if (!ht.containsKey(key))

{

ht.put(key,

value);

} else { //

如果已經有了同名的KEY,就要把當前的key更名,同時要注意不能構成和KEY同名

try {

Thread.currentThread().sleep(1);

// 為了不在同一ms中產生兩個相同的key

} catch

(Exception e) {

}

key +=

"||||||||||" + System.currentTimeMillis();

ht.put(key,

value);

}

}

private String readLine(byte[] Linebyte,

ServletInputStream

servletinputstream, String charset) {

try {

len =

servletinputstream.readLine(Linebyte, 0, Linebyte.length);

if (len ==

-1) {

return

null;

}

if (charset

== null) {

return

new String(Linebyte, 0, len);

} else

{

return

new String(Linebyte, 0, len, charset);

}

} catch (Exception _ex)

{

return

null;

}

}

private String getFileName(String line) { //

從描述字符串中分離出文件名

if (line == null) {

return

"";

}

int i =

line.indexOf("filename=");

line = line.substring(i +

9).trim();

i = line.lastIndexOf("");

if (i < 0 || i

>= line.length() - 1) {

i =

line.lastIndexOf("\\");

if

(line.equals("\"\"")) {

return

"";

}

if (i

< 0 || i >= line.length() - 1)

{

return

line;

}

}

return line.substring(i + 1,

line.length() - 1);

}

private String getKey(String line) {

//從描述字符串中分離出字段名

if (line == null) {

return

"";

}

int i =

line.indexOf("name=");

line = line.substring(i +

5).trim();

return line.substring(1,

line.length() - 1);

}

public static String[] split(String strOb,

String mark) {

if (strOb == null) {

return

null;

}

StringTokenizer st = new

StringTokenizer(strOb, mark);

ArrayList tmp = new

ArrayList();

while (st.hasMoreTokens())

{

tmp.add(st.nextToken());

}

String[] strArr = new

String[tmp.size()];

for (int i = 0; i

< tmp.size(); i++) {

strArr[i] =

(String) tmp.get(i);

}

return strArr;

}

}