微信公众平台上传多媒体文件-JAVA

/**
* 模拟表单进行多媒体传输
* 
* @param requestUrl （请求地址）
* @param requestMethod  (默认方法)
* @param fileName  （文件名字）
* @param contentType (文件类型)
* @param file (文件内容)
* @return
* @throws Exception
*/
public static JSONObject uploadMultimedia(String requestUrl,
String requestMethod, String fileName, String contentType,String filePath)
throws Exception {
String result = null;
JSONObject jsonObject = null;
File file = new File(filePath);  
   if (!file.exists() || !file.isFile()) {  
   throw new IOException("文件不存在");  
   }  
try {
URL url = new URL(requestUrl);
HttpURLConnection con = (HttpURLConnection) url.openConnection();


con.setRequestMethod(requestMethod); // 以Post方式提交表单，默认get方式
con.setDoInput(true);
con.setDoOutput(true);
con.setUseCaches(false); // post方式不能使用缓存


// 设置请求头信息
con.setRequestProperty("Connection", "Keep-Alive");
con.setRequestProperty("Charset", "UTF-8");
// 设置边界
String BOUNDARY = "----------" + System.currentTimeMillis();
con.setRequestProperty("Content-Type",
"multipart/form-data; boundary=" + BOUNDARY);
StringBuilder sb = new StringBuilder();
sb.append("--"); // 必须多两道线
sb.append(BOUNDARY);
sb.append("\r\n");
sb.append("Content-Disposition: form-data;name=\"file\";filename=\""
+ fileName + "\"\r\n");
sb.append("Content-Type:application/octet-stream\r\n\r\n");


byte[] head = sb.toString().getBytes("utf-8");
OutputStream out = new DataOutputStream(con.getOutputStream());
out.write(head);


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[] foot = ("\r\n--" + BOUNDARY + "--\r\n").getBytes("utf-8");// 定义最后数据分隔线
out.write(foot);


out.flush();
out.close();


StringBuffer buffer = new StringBuffer();
BufferedReader reader = null;
try {
reader = new BufferedReader(new InputStreamReader(
con.getInputStream()));
String line = null;
while ((line = reader.readLine()) != null) {
buffer.append(line);
}
if (result == null) {
result = buffer.toString();
}
} catch (IOException e) {
System.out.println("发送POST请求出现异常！" + e);
e.printStackTrace();
throw new IOException("数据读取异常");
} finally {
if (reader != null) {
reader.close();
}

}
String str = buffer.toString();
System.out.println("结果："+str);
jsonObject = JSONObject.parseObject(buffer.toString());
} catch (Exception e) {
// logger.debug("抓取HTTPS请求出错: " + e.getMessage());
throw new Exception(e.getMessage());
}
return jsonObject;

}

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