/**

* 上传文件

*/

public static String sendFile(String urlPath, String filePath,

String newName) throws Exception {

String end = "\r\n";

String twoHyphens = "--";

String boundary = "*****";

URL url = new URL(urlPath);

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

/* 允许Input、Output，不使用Cache */

con.setDoInput(true);

con.setDoOutput(true);

con.setUseCaches(false);

/* 设置传送的method=POST */

con.setRequestMethod("POST");

/* setRequestProperty */

con.setRequestProperty("Connection", "Keep-Alive");

con.setRequestProperty("Charset", "UTF-8");

con.setRequestProperty("Content-Type", "multipart/form-data;boundary="

+ boundary);

/* 设置DataOutputStream */

DataOutputStream ds = new DataOutputStream(con.getOutputStream());

ds.writeBytes(twoHyphens + boundary + end);

ds.writeBytes("Content-Disposition: form-data; "

+ "name=\"file1\";filename=\"" + newName + "\"" + end);

ds.writeBytes(end);

/* 取得文件的FileInputStream */

FileInputStream fStream = new FileInputStream(filePath);

/* 设置每次写入1024bytes */

int bufferSize = 1024;

byte[] buffer = new byte[bufferSize];

int length = -1;

/* 从文件读取数据至缓冲区 */

while ((length = fStream.read(buffer)) != -1) {

/* 将资料写入DataOutputStream中 */

ds.write(buffer, 0, length);

}

ds.writeBytes(end);

ds.writeBytes(twoHyphens + boundary + twoHyphens + end);

/* close streams */

fStream.close();

ds.flush();

/* 取得Response内容 */

InputStream is = con.getInputStream();

int ch;

StringBuffer b = new StringBuffer();

while ((ch = is.read()) != -1) {

b.append((char) ch);

}

/* 关闭DataOutputStream */

ds.close();

return b.toString();

}

原帖地址：http://blog.csdn.net/lk_blog/article/details/7706348