Create oauth_signture in flickr for getting access token - oauth

Question

I am new to flickr API.Some where i get the code to create the signature for getting request token.but i cant able to create it for the access token.Always says that the signature is invalid.
i am using the code for creating signature is
private static String getreqSignature(String url, String params)
throws UnsupportedEncodingException, NoSuchAlgorithmException,
InvalidKeyException {
StringBuilder base = new StringBuilder();
base.append("GET&");
base.append(url);
base.append("&");
base.append(params);
System.out.println("Stirng for oauth_signature generation:" + base);
// yea, don't ask me why, it is needed to append a "&" to the end of
// secret key.
byte[] keyBytes = (ApplicationContext.getFLICKR_API_SECRET() + "&")
.getBytes(ENC);
SecretKey key = new SecretKeySpec(keyBytes, HMAC_SHA1);
Mac mac = Mac.getInstance(HMAC_SHA1);
mac.init(key);
System.out.println(new String(base64.encode(mac.doFinal(base.toString()
.getBytes(ENC))), ENC));
// encode it, base64 it, change it to string and return.
return new String(base64.encode(mac.doFinal(base.toString().getBytes(
ENC))), ENC).trim();
}
My query parameters are
qparams.add(new BasicNameValuePair("oauth_consumer_key","******"));
qparams.add(new BasicNameValuePair("oauth_nonce", ""+ (int) (Math.random() * 100000000)));
qparams.add(new BasicNameValuePair("oauth_signature_method","HMAC-SHA1"));
qparams.add(new BasicNameValuePair("oauth_timestamp", ""+ (System.currentTimeMillis() / 1000)));
qparams.add(new BasicNameValuePair("oauth_version", "1.0"));
// generate the oauth_signature
String signature = getreqSignature(URLEncoder.encode(
"http://www.flickr.com/services/oauth/request_token", ENC),
URLEncoder.encode(URLEncodedUtils.format(qparams, ENC), ENC));
// qparams.add(new BasicNameValuePair("oauth_verifier", verifier));
qparams.add(new BasicNameValuePair("oauth_signature", signature));
URI uri = URIUtils.createURI("http", "www.flickr.com", -1,
"/services/oauth/request_token",
URLEncodedUtils.format(qparams, ENC), null);
How to create signature to get access token.What to change in the above code.

Answer 1

finally i used Scribe library to get my details.Its working fine.