Upload up = new Upload();
up.init(request);
/**
此處可以調用setSaveDir(String saveDir);設置保存路徑
調用setMaxFileSize(long size)設置上傳文件的最大字節.
調用setTagFileName(String)設置上傳後文件的名字(只對第一個文件有效)
*/
up. uploadFile();
然後String[] names = up.getFileName();得到上傳的文件名,文件絕對路徑應該是
保存的目錄saveDir+"/"+names[i];
可以通過up.getParameter("field");得到上傳的文本或up.getParameterValues("filed")
得到同名字段如多個checkBox的值.
其它的自己試試.
源碼:____________________________________________________________
package com.inmsg.beans;
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,用於初始化
private HttpServletRequest request; //用於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) { //用於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) { //用於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); //爲了保證目錄存在,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數據爲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); //爲了不在同一ms中產生兩個相同的key
}
catch (Exception e) {}
key += "||||||||||" + System.currentTimeMillis();
ht.put(key, value);
}
}
/*
調用ServletInputstream.readLine(byte[] b,int offset,length)方法,該方法是從ServletInputstream流中讀一行
到指定的byte數組,爲了保證能夠容納一行,該byte[]b不應該小於256,重寫的readLine中,調用了一個成員變量len爲
實際讀到的字節數(有的行不滿256),則在文件內容寫入時應該從byte數組中寫入這個len長度的字節而不是整個byte[]
的長度,但重寫的這個方法返回的是String以便分析實際內容,不能返回len,所以把len設爲成員變量,在每次讀操作時
把實際長度賦給它.
也就是說在處理到文件的內容時數據既要以String形式返回以便分析開始和結束標記,又要同時以byte[]的形式寫到文件
輸出流中.
*/
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;
}
}