Java代码实现

/**

* 模拟文件post上传

* @param urlStr(接口地址)

* @param formName(接口file接收名)

* @param fileName(需要上传文件的本地路径)

* @return文件上传到接口返回的结果

*/

public static String uploadFile(String urlStr, String formName, String fileName) {

String baseResult = null;

try {

final String newLine = "\r\n";

final String boundaryPrefix = "--";

String BOUNDARY = "========7d4a6d158c9";// 模拟数据分隔线

URL url = new URL(urlStr);

HttpURLConnection conn = (HttpURLConnection) url.openConnection();

conn.setRequestMethod("POST");// 设置为POST请求

conn.setDoOutput(true);

conn.setDoInput(true);

conn.setRequestProperty("connection", "Keep-Alive");// 设置请求头参数

conn.setRequestProperty("Charsert", "UTF-8");

conn.setRequestProperty("Content-Type","multipart/form-data; boundary=" + BOUNDARY);

OutputStream out = conn.getOutputStream();

File file = new File(fileName);

StringBuilder sb = new StringBuilder();

sb.append(boundaryPrefix);

sb.append(BOUNDARY);

sb.append(newLine);

sb.append("Content-Disposition: form-data;name=\""+formName+"\";filename=\""+ fileName + "\"" + newLine);

sb.append("Content-Type:application/octet-stream");

sb.append(newLine);

sb.append(newLine);

out.write(sb.toString().getBytes());// 将参数头的数据写入到输出流中

DataInputStream in = new DataInputStream(new FileInputStream(file));// 数据输入流,用于读取文件数据

byte[] bufferOut = new byte[1024];

int bytes = 0;

while ((bytes = in.read(bufferOut)) != -1) {// 每次读1KB数据,并且将文件数据写入到输出流中

out.write(bufferOut, 0, bytes);

}

out.write(newLine.getBytes());

in.close();

byte[] end_data = (newLine + boundaryPrefix + BOUNDARY

+ boundaryPrefix + newLine).getBytes();

out.write(end_data);

out.flush();

out.close();

BufferedReader reader = new BufferedReader(new InputStreamReader(

conn.getInputStream()));

String line = null;

StringBuffer strs = new StringBuffer("");

while ((line = reader.readLine()) != null) {

strs.append(line);

}

baseResult = strs;

} catch (Exception e) {

baseResult = e.getMessage();

}

return baseResult;

}