表單上傳是使用HTML表單形式上傳檔案到指定儲存空間中，檔案最大不能超過5GB。
表單上傳的適用場景介紹請參見開發指南中的表單上傳。PostObject更詳情資訊請參見Java模擬PostObject表單上傳OSS。
以下代碼用於表單上傳：
public class PostObjectSample {// 上傳檔案private String localFilePath = "<yourLocalFile>";// Endpoint以杭州為例，其它Region請按實際情況填寫。private String endpoint = "http://oss-cn-hangzhou.aliyuncs.com";// 阿里雲主帳號AccessKey擁有所有API的存取權限，風險很高。強烈建議您建立並使用RAM帳號進行API訪問或日常運維，請登入 https://ram.console.aliyun.com 建立RAM帳號。private String accessKeyId = "<yourAccessKeyId>";private String accessKeySecret = "<yourAccessKeySecret>";// 儲存空間名稱private String bucketName = "<yourBucketName>";// 檔案名稱private String objectName = "<yourObjectName>";/*** 表單上傳* @throws Exception*/private void PostObject() throws Exception {// 在URL中添加儲存空間名稱，添加後URL如下：http://yourBucketName.oss-cn-hangzhou.aliyuncs.comString urlStr = endpoint.replace("http://", "http://" + bucketName+ ".");// 表單Map。Map<String, String> formFields = new LinkedHashMap<String, String>();// 設定檔案名稱。formFields.put("key", this.objectName);// 設定Content-Disposition。formFields.put("Content-Disposition", "attachment;filename="+ localFilePath);// 設定回調參數。Callback callback = new Callback();// 設定回調伺服器位址，如http://oss-demo.aliyuncs.com:23450或http://127.0.0.1:9090。callback.setCallbackUrl("<yourCallbackServerUrl>");// 設定回調請求消息頭中Host的值，如oss-cn-hangzhou.aliyuncs.com。callback.setCallbackHost("<yourCallbackServerHost>");// 設定發起回調時請求body的值。callback.setCallbackBody("{\\\"mimeType\\\":${mimeType},\\\"size\\\":${size}}");// 設定發起回調請求的Content-Type。callback.setCalbackBodyType(CalbackBodyType.JSON);// 設定發起回調請求的自訂參數，由Key和Value組成，Key必須以x:開始。callback.addCallbackVar("x:var1", "value1");callback.addCallbackVar("x:var2", "value2");// 在表單Map中設定回調參數。setCallBack(formFields, callback);// 設定OSSAccessKeyId。formFields.put("OSSAccessKeyId", accessKeyId);String policy = "{\"expiration\": \"2120-01-01T12:00:00.000Z\",\"conditions\": [[\"content-length-range\", 0, 104857600]]}";String encodePolicy = new String(Base64.encodeBase64(policy.getBytes()));// 設定policy。formFields.put("policy", encodePolicy);// 生成簽名。String signaturecom = com.aliyun.oss.common.auth.ServiceSignature.create().computeSignature(accessKeySecret, encodePolicy);// 設定簽名。formFields.put("Signature", signaturecom);String ret = formUpload(urlStr, formFields, localFilePath);System.out.println("Post Object [" + this.objectName + "] to bucket [" + bucketName + "]");System.out.println("post reponse:" + ret);}private static String formUpload(String urlStr, Map<String, String> formFields, String localFile)throws Exception {String res = "";HttpURLConnection conn = null;String boundary = "9431149156168";try {URL url = new URL(urlStr);conn = (HttpURLConnection) url.openConnection();conn.setConnectTimeout(5000);conn.setReadTimeout(30000);conn.setDoOutput(true);conn.setDoInput(true);conn.setRequestMethod("POST");conn.setRequestProperty("User-Agent","Mozilla/5.0 (Windows; U; Windows NT 6.1; zh-CN; rv:1.9.2.6)");// 設定MD5值。MD5值是由整個body計算得出的。conn.setRequestProperty("Content-MD5", "<yourContentMD5>");conn.setRequestProperty("Content-Type","multipart/form-data; boundary=" + boundary);OutputStream out = new DataOutputStream(conn.getOutputStream());// 遍曆讀取表單Map中的資料，將資料寫入到輸出資料流中。if (formFields != null) {StringBuffer strBuf = new StringBuffer();Iterator<Entry<String, String>> iter = formFields.entrySet().iterator();int i = 0;while (iter.hasNext()) {Entry<String, String> entry = iter.next();String inputName = entry.getKey();String inputValue = entry.getValue();if (inputValue == null) {continue;}if (i == 0) {strBuf.append("--").append(boundary).append("\r\n");strBuf.append("Content-Disposition: form-data; name=\""+ inputName + "\"\r\n\r\n");strBuf.append(inputValue);} else {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);}i++;}out.write(strBuf.toString().getBytes());}// 讀取檔案資訊，將要上傳的檔案寫入到輸出資料流中。File file = new File(localFile);String filename = file.getName();String contentType = new MimetypesFileTypeMap().getContentType(file);if (contentType == null || contentType.equals("")) {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=\"file\"; "+ "filename=\"" + filename + "\"\r\n");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。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.err.println("Send post request exception: " + e);throw e;} finally {if (conn != null) {conn.disconnect();conn = null;}}return res;}private static void setCallBack(Map<String, String> formFields, Callback callback) {if (callback != null) {String jsonCb = OSSUtils.jsonizeCallback(callback);String base64Cb = BinaryUtil.toBase64String(jsonCb.getBytes());formFields.put("callback", base64Cb);if (callback.hasCallbackVar()) {Map<String, String> varMap = callback.getCallbackVar();for (Entry<String, String> entry : varMap.entrySet()) {formFields.put(entry.getKey(), entry.getValue());}}}}public static void main(String[] args) throws Exception {PostObjectSample ossPostObject = new PostObjectSample();ossPostObject.PostObject();}}