java 调用 .net 发布 webservice 传递 byte[]

public static void MakeThumbnail(byte[] ImageCount, String thumbnailPath, int width, int height, String mode, String rename, String format) throws Exception {

    URL wsUrl = new URL(URL);

    HttpURLConnection conn = (HttpURLConnection) wsUrl.openConnection();
    conn.setDoInput(true);
    conn.setDoOutput(true);
    conn.setRequestMethod("POST");
    conn.setRequestProperty("Content-Type", "text/xml;charset=UTF-8");
    OutputStream os = conn.getOutputStream();

    // 请求体
    String soap = "<soap:Envelope xmlns:xsi=\"http://www.w3.org/2001/XMLSchema-instance\" xmlns:xsd=\"http://www.w3.org/2001/XMLSchema\" xmlns:soap=\"http://schemas.xmlsoap.org/soap/envelope/\">"
            + "<soap:Body>"
            + "<MakeThumbnail xmlns=\"http://www.520shq.com/\">"
            + "<ImageCount>"
            + ImageCount
            + "</ImageCount>"
            + "<thumbnailPath>"
            + thumbnailPath
            + "</thumbnailPath>"
            + "<width>"
            + width
            + "</width>"
            + "<height>"
            + height
            + "</height>"
            + "<mode>"
            + mode
            + "</mode>"
            + "<rename>"
            + rename
            + "</rename>"
            + "<format>"
            + format
            + "</format>"
            + "</MakeThumbnail>"
            + "</soap:Body></soap:Envelope>";

    os.write(soap.getBytes());
    InputStream is = conn.getInputStream();

    byte[] b = new byte[1024];
    int len = 0;
    String xml = "";
    while ((len = is.read(b)) != -1) {
        xml += new String(b, 0, len, "UTF-8");
    }

    is.close();
    os.close();
    conn.disconnect();

    我只要传递byte[] 就会报400 求大神帮帮忙！

http://www.cnblogs.com/cpcpc/archive/2011/06/27/2123010.html