public static boolean isValidValue(String value) {
    return ((value != null) && value.startsWith(VALUE_PREFIX));
  }
Renders a new PrincipalKeyCredential from its value representation

@param value a String containing the value representation of this PrincipalKeyCredential
@return a new PrincipalKeyCredential or null if a new PrincipalKeyCredential cannot be created
ambari-server/src/main/java/org/apache/ambari/server/security/credential/PrincipalKeyCredential.java