@Override
			public B read(final XMLStreamReader xml)
				throws XMLStreamException {
				try {
					return mapper.apply(Reader.this.read(xml));
				} catch (RuntimeException e) {
					throw new XMLStreamException(e);
				}
			}
Create a new reader for the new mapped type {@code B}.

@param mapper the mapper function
@param <B> the target type of the new reader
@return a new reader
@throws NullPointerException if the given {@code mapper} function is
        {@code null}
jenetics.xml/src/main/java/io/jenetics/xml/stream/Reader.java