code: @Pure
  	public static int compareAttrs(Attribute arg0, Attribute arg1) {
  		if (arg0 == arg1) {
  			return 0;
  		}
  		if (arg0 == null) {
  			return 1;
  		}
  		if (arg1 == null) {
  			return -1;
  		}
  
  		final String n0 = arg0.getName();
  		final String n1 = arg1.getName();
  		final int cmp = compareAttrNames(n0, n1);
  
  		if (cmp == 0) {
  			return compareValues(arg0, arg1);
  		}
  
  		return cmp;
  	}
docs: Compare the two specified attributes.
  
  @param arg0 first attribute
  @param arg1 second attribute.
  @return replies a negative value if {@code arg0} is lesser than
  {@code arg1}, a positive value if {@code arg0} is greater than
  {@code arg1}, or <code>0</code> if they are equal.
  @see AttributeComparator