code: @Override
  	public synchronized boolean checkPermission(Principal aPrincipal, String aPermission)
  	{
  		if (aPermission == null)
  			return false;
  
  		SecurityPermission securityPermission = new SecurityPermission(aPermission);
  
  		return this.checkPermission(aPrincipal, securityPermission);
  	}
docs: /*
  (non-Javadoc)
  
  @see nyla.solutions.core.security.data.Acl#checkPermission(java.security.
  Principal, java.lang.String)