src/main/java/org/imsglobal/lti/BasicLTIUtil.java
public static Properties signProperties(Properties postProp, String url,
            String method, String oauth_consumer_key, String oauth_consumer_secret,
            String org_id, String org_desc, String org_url) {
        final Map<String, String> signedMap = signProperties(
                convertToMap(postProp), url, method, oauth_consumer_key,
                oauth_consumer_secret, org_id, org_desc, org_url, null, null);
        return convertToProperties(signedMap);
    }
public static Properties signProperties(Properties postProp, String url,
            String method, String oauth_consumer_key, String oauth_consumer_secret,
            String org_id, String org_desc, String org_url) {
        final Map<String, String> signedMap = signProperties(
                convertToMap(postProp), url, method, oauth_consumer_key,
                oauth_consumer_secret, org_id, org_desc, org_url, null, null);
        return convertToProperties(signedMap);
    }
Add the necessary fields and sign.

@deprecated See:
{@link BasicLTIUtil#signProperties(Map, String, String, String, String, String, String, String, String, String)}

@param postProp
@param url
@param method
@param oauth_consumer_key
@param oauth_consumer_secret
@param org_id See: {@link BasicLTIConstants#TOOL_CONSUMER_INSTANCE_GUID}
@param org_desc See:
{@link BasicLTIConstants#TOOL_CONSUMER_INSTANCE_DESCRIPTION}
@param org_url See: {@link BasicLTIConstants#TOOL_CONSUMER_INSTANCE_URL}
@return