Java 中HttpURLConnection附件上傳的實例詳解
更新時間:2017年09月17日 09:49:21 作者:xiaobojava
這篇文章主要介紹了Java 中HttpURLConnection附件上傳的實例詳解的相關資料,希望通過本文大家能掌握這樣的知識內(nèi)容,需要的朋友可以參考下
Java 中HttpURLConnection附件上傳的實例詳解
整合了一個自己寫的采用Http做附件上傳的工具,分享一下!
示例代碼:
/** * 以Http協(xié)議傳輸文件 * * @author mingxue.zhang@163.com * */ public class HttpPostUtil { private final static char[] MULTIPART_CHARS = "-_1234567890abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ" .toCharArray(); private URL url; private HttpURLConnection conn; private String boundary = null; private Map<String, String> textParams = new HashMap<String, String>(); private Map<String, File> fileparams = new HashMap<String, File>(); public HttpPostUtil(String url) throws Exception { this.url = new URL(url); } // 重新設置要請求的服務器地址,即上傳文件的地址。 public void setUrl(String url) throws Exception { this.url = new URL(url); } // 增加一個普通字符串數(shù)據(jù)到form表單數(shù)據(jù)中 public void addTextParameter(String name, String value) { textParams.put(name, value); } // 增加一個文件到form表單數(shù)據(jù)中 public void addFileParameter(String name, File value) { fileparams.put(name, value); } // 清空所有已添加的form表單數(shù)據(jù) public void clearAllParameters() { textParams.clear(); fileparams.clear(); } /** * 發(fā)送數(shù)據(jù)到服務器 * * @return 一個字節(jié)包含服務器的返回結果的數(shù)組 * @throws Exception */ public byte[] send() throws Exception { initConnection(); try { conn.connect(); } catch (SocketTimeoutException e) { throw new Exception(e); } OutputStream connOutStream = new DataOutputStream( conn.getOutputStream()); writeFileParams(connOutStream); writeStringParams(connOutStream); writesEnd(connOutStream); InputStream responseInStream = conn.getInputStream(); ByteArrayOutputStream responseOutStream = new ByteArrayOutputStream(); int len; byte[] bufferByte = new byte[1024]; while ((len = responseInStream.read(bufferByte)) != -1) { responseOutStream.write(bufferByte, 0, len); } responseInStream.close(); connOutStream.close(); conn.disconnect(); byte[] resultByte = responseOutStream.toByteArray(); responseOutStream.close(); return resultByte; } // 文件上傳的connection的一些必須設置 private void initConnection() throws Exception { StringBuffer buf = new StringBuffer("----"); Random rand = new Random(); for (int i = 0; i < 15; i++) { buf.append(MULTIPART_CHARS[rand.nextInt(MULTIPART_CHARS.length)]); } this.boundary = buf.toString(); conn = (HttpURLConnection) this.url.openConnection(); conn.setDoOutput(true); conn.setUseCaches(false); conn.setConnectTimeout(3 * 60 * 1000); // 連接超時為10秒 conn.setRequestMethod("POST"); conn.setRequestProperty("Content-Type", "multipart/form-data; boundary=" + boundary); } // 普通字符串數(shù)據(jù) private void writeStringParams(OutputStream out) throws Exception { Set<String> keySet = textParams.keySet(); for (Iterator<String> it = keySet.iterator(); it.hasNext();) { String name = it.next(); String value = textParams.get(name); out.write(("--" + boundary + "\r\n").getBytes()); out.write(("Content-Disposition: form-data; name=\"" + name + "\"\r\n") .getBytes()); out.write(("\r\n").getBytes()); out.write((encode(value) + "\r\n").getBytes()); } } // 文件數(shù)據(jù) private void writeFileParams(OutputStream out) throws Exception { Set<String> keySet = fileparams.keySet(); for (Iterator<String> it = keySet.iterator(); it.hasNext();) { String name = it.next(); File value = fileparams.get(name); out.write(("--" + boundary + "\r\n").getBytes()); out.write(("Content-Disposition: form-data; name=\"" + name + "\"; filename=\"" + encode(value.getName()) + "\"\r\n") .getBytes()); out.write(("Content-Type: " + getContentType(value) + "\r\n") .getBytes()); out.write(("Content-Transfer-Encoding: " + "binary" + "\r\n") .getBytes()); out.write(("\r\n").getBytes()); FileInputStream inStream = new FileInputStream(value); int bytes = 0; byte[] bufferByte = new byte[1024]; while ((bytes = inStream.read(bufferByte)) != -1) { out.write(bufferByte, 0, bytes); } inStream.close(); out.write(("\r\n").getBytes()); } } // 添加結尾數(shù)據(jù) private void writesEnd(OutputStream out) throws Exception { out.write(("--" + boundary + "--" + "\r\n").getBytes()); out.write(("\r\n").getBytes()); } // 獲取文件的上傳類型,圖片格式為image/png,image/jpg等。非圖片為application/octet-stream private String getContentType(File f) throws Exception { String fileName = f.getName(); if (fileName.endsWith(".jpg")) { return "image/jpeg"; } else if (fileName.endsWith(".png")) { return "image/png"; } return "application/octet-stream"; } // 對包含中文的字符串進行轉(zhuǎn)碼,此為UTF-8。服務器那邊要進行一次解碼 private String encode(String value) throws Exception { return URLEncoder.encode(value, "UTF-8"); } }
如有疑問請留言或者到本站社區(qū)交流討論,感謝閱讀,希望能幫助到大家,謝謝大家對本站的支持!
相關文章
Java中ConcurrentHashMap和Hashtable的區(qū)別
ConcurrentHashMap?和?Hashtable?都是用于在Java中實現(xiàn)線程安全的哈希表數(shù)據(jù)結構的類,但它們有很多區(qū)別,本文就來詳細的介紹一下,感興趣的可以了解一下2023-10-10淺談springmvc 通過異常增強返回給客戶端統(tǒng)一格式
這篇文章主要介紹了淺談springmvc 通過異常增強返回給客戶端統(tǒng)一格式。具有很好的參考價值,希望對大家有所幫助。一起跟隨小編過來看看吧2020-09-09Spring?Boot使用MyBatis進行兩個表的關聯(lián)
本文主要介紹了Spring?Boot使用MyBatis進行兩個表的關聯(lián),通過實例演示了如何使用MyBatis的XML映射文件和注解實現(xiàn)關聯(lián)操作,具有一定的參考價值,感興趣的可以了解一下2023-09-09java 中HashMap、HashSet、TreeMap、TreeSet判斷元素相同的幾種方法比較
這篇文章主要介紹了從源碼的角度淺析HashMap、TreeMap元素的存儲和獲取元素的邏輯;從Map與Set之間的關系淺析常用的Set中元素的存儲和判斷是否重復的邏輯,需要的朋友可以參考下2017-01-01