code: protected AbcNode getParseTree(Reader reader) throws IOException {
  		StringWriter writer = new StringWriter();
  		char[] buffer = new char[32 * 1024];
  		int n;
  		while ((n = reader.read(buffer)) != -1) {
  			writer.write(buffer, 0, n);
  		}
  		return getParseTree(writer.toString());
  	}
docs: Parse the {@link Reader} and get the parsing tree by its root
  {@link AbcNode}.
  
  @param reader
  @see #getParseTree(String) the whole content of the reader is read as
  String
  @throws IOException