code: private static void checkPreconditions(final int maxSize, final String suffix) {
  		if( maxSize <= 0 ) {
  			throw new IllegalArgumentException(String.format("maxSize should be > 0 but was %d", maxSize));
  		}
  		if( suffix == null ) {
  			throw new NullPointerException("suffix should not be null");
  		}
  	}
docs: Checks the preconditions for creating a new Truncate processor.
  
  @param maxSize
  the maximum size of the String
  @param suffix
  the String to append if the input is truncated (e.g. "...")
  @throws IllegalArgumentException
  if {@code maxSize <= 0}
  @throws NullPointerException
  if suffix is null