Examples with ETagGenerationException org.wso2.carbon.apimgt.core.exception.ETagGenerationException used on opensource projects

Example 1 with ETagGenerationException

use of org.wso2.carbon.apimgt.core.exception.ETagGenerationException in project carbon-apimgt by wso2.

the class ETagUtils method getHash.

/**
 * If some other hashing algorithm is needed use this method.
 *
 * @param updatedTime, the updated/created time of the resource in UNIX time
 * @param algorithm            the algorithm used for hashing
 * @return String
 * @throws NoSuchAlgorithmException if the given algorithm is invalid or not found in {@link MessageDigest}
 * @throws ETagGenerationException if hash generation failed.
 */
private static String getHash(String updatedTime, String algorithm) throws ETagGenerationException, NoSuchAlgorithmException {
    MessageDigest messageDigest = MessageDigest.getInstance(algorithm);
    try {
        messageDigest.update(updatedTime.getBytes("UTF-8"));
        byte[] digest = messageDigest.digest();
        // conversion to hexadecimal
        StringBuilder sb = new StringBuilder();
        for (byte b : digest) {
            sb.append(String.format("%02x", b & 0xff));
        }
        String generatedHash = sb.toString();
        if (log.isDebugEnabled()) {
            log.debug("ETag generated in HEX '" + generatedHash + "' for '" + updatedTime + "'");
        }
        return sb.toString();
    } catch (UnsupportedEncodingException e) {
        String errorMessage = "Error while converting timestamp to String :" + updatedTime;
        log.error(errorMessage, e);
        throw new ETagGenerationException(errorMessage, e);
    }
}