/**
	 * 測試上傳png圖片
	 * 
	 */
	public static void testUploadImage(){
		 String url = "http://localhost:8080/app/remindDetails/doRepair.xhtml";
	        String fileName = "E:\\工作\\專案\\奇瑞只能製造資訊化系統\\工作安排\\介面設計(20171113-)\\1.5.png";
		Map<String, String> textMap = new HashMap<String, String>();
		//普通引數：可以設定多個input的name，value
		textMap.put("name", "testname");
		textMap.put("type", "2");
		//檔案：設定file的name，路徑
		Map<String, String> fileMap = new HashMap<String, String>();
		fileMap.put("upfile", fileName);
		String contentType = "";//image/png
		 formUpload(url, textMap, fileMap,contentType);
	}


	/**
	 * 上傳圖片
	 * @param urlStr
	 * @param textMap
	 * @param fileMap
	 * @param contentType 沒有傳入檔案型別預設採用application/octet-stream
	 * contentType非空採用filename匹配預設的圖片型別
	 * @return 返回response資料
	 */
	@SuppressWarnings("rawtypes")
	public static String formUpload(String urlStr, Map<String, String> textMap,
			Map<String, String> fileMap,String contentType) {
		String res = "";
		HttpURLConnection conn = null;
		// boundary就是request頭和上傳檔案內容的分隔符
		String BOUNDARY = "---------------------------123821742118716"; 
		try {
			URL url = new URL(urlStr);
			conn = (HttpURLConnection) url.openConnection();
			conn.setConnectTimeout(5000);
			conn.setReadTimeout(30000);
			conn.setDoOutput(true);
			conn.setDoInput(true);
			conn.setUseCaches(false);
			conn.setRequestMethod("POST");
			conn.setRequestProperty("Connection", "Keep-Alive");
			conn.setRequestProperty("User-Agent",
					"Mozilla/5.0 (Windows; U; Windows NT 6.1; zh-CN; rv:1.9.2.6)");
			conn.setRequestProperty("Content-Type",
					"multipart/form-data; boundary=" + BOUNDARY);
			OutputStream out = new DataOutputStream(conn.getOutputStream());
			// text
			if (textMap != null) {
				StringBuffer strBuf = new StringBuffer();
				Iterator iter = textMap.entrySet().iterator();
				while (iter.hasNext()) {
					Map.Entry entry = (Map.Entry) iter.next();
					String inputName = (String) entry.getKey();
					String inputValue = (String) entry.getValue();
					if (inputValue == null) {
						continue;
					}
					strBuf.append("\r\n").append("--").append(BOUNDARY)
							.append("\r\n");
					strBuf.append("Content-Disposition: form-data; name=\""
							+ inputName + "\"\r\n\r\n");
					strBuf.append(inputValue);
					System.out.println(inputName+","+inputValue);
				}
				out.write(strBuf.toString().getBytes());
			}
			// file
			if (fileMap != null) {
				Iterator iter = fileMap.entrySet().iterator();
				while (iter.hasNext()) {
					Map.Entry entry = (Map.Entry) iter.next();
					String inputName = (String) entry.getKey();
					String inputValue = (String) entry.getValue();
					if (inputValue == null) {
						continue;
					}
					File file = new File(inputValue);
					String filename = file.getName();
					
					//沒有傳入檔案型別，同時根據檔案獲取不到型別，預設採用application/octet-stream
					contentType = new MimetypesFileTypeMap().getContentType(file);
					//contentType非空採用filename匹配預設的圖片型別
					if(!"".equals(contentType)){
						if (filename.endsWith(".png")) {
							contentType = "image/png"; 
						}else if (filename.endsWith(".jpg") || filename.endsWith(".jpeg") || filename.endsWith(".jpe")) {
							contentType = "image/jpeg";
						}else if (filename.endsWith(".gif")) {
							contentType = "image/gif";
						}else if (filename.endsWith(".ico")) {
							contentType = "image/image/x-icon";
						}
					}
					if (contentType == null || "".equals(contentType)) {
						contentType = "application/octet-stream";
					}
					StringBuffer strBuf = new StringBuffer();
					strBuf.append("\r\n").append("--").append(BOUNDARY)
							.append("\r\n");
					strBuf.append("Content-Disposition: form-data; name=\""
							+ inputName + "\"; filename=\"" + filename
							+ "\"\r\n");
					System.out.println(inputName+","+filename);
					
					strBuf.append("Content-Type:" + contentType + "\r\n\r\n");
					out.write(strBuf.toString().getBytes());
					DataInputStream in = new DataInputStream(
							new FileInputStream(file));
					int bytes = 0;
					byte[] bufferOut = new byte[1024];
					while ((bytes = in.read(bufferOut)) != -1) {
						out.write(bufferOut, 0, bytes);
					}
					in.close();
				}
			}
			byte[] endData = ("\r\n--" + BOUNDARY + "--\r\n").getBytes();
			out.write(endData);
			out.flush();
			out.close();
			// 讀取返回資料
			StringBuffer strBuf = new StringBuffer();
			BufferedReader reader = new BufferedReader(new InputStreamReader(
					conn.getInputStream()));
			String line = null;
			while ((line = reader.readLine()) != null) {
				strBuf.append(line).append("\n");
			}
			res = strBuf.toString();
			reader.close();
			reader = null;
		} catch (Exception e) {
			System.out.println("傳送POST請求出錯。" + urlStr);
			e.printStackTrace();
		} finally {
			if (conn != null) {
				conn.disconnect();
				conn = null;
			}
		}
		return res;
	}

 

採用Java自帶的HttpURLConnection實現的

轉自：http://blog.csdn.net/wangpeng047/article/details/38303865#reply

程式碼見http://download.csdn.net/download/jaedons/10123268