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The DSI utilities are a mishmash of classes accumulated during the last twenty years in projects developed at the DSI (Dipartimento di Scienze dell'Informazione, i.e., Information Sciences Department), now DI (Dipartimento di Informatica, i.e., Informatics Department), of the Universita` degli Studi di Milano.

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package it.unimi.dsi.io;

/*
 * DSI utilities
 *
 * Copyright (C) 2006-2019 Sebastiano Vigna
 *
 *  This library is free software; you can redistribute it and/or modify it
 *  under the terms of the GNU Lesser General Public License as published by the Free
 *  Software Foundation; either version 3 of the License, or (at your option)
 *  any later version.
 *
 *  This library is distributed in the hope that it will be useful, but
 *  WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
 *  or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public License
 *  for more details.
 *
 *  You should have received a copy of the GNU Lesser General Public License
 *  along with this program; if not, see .
 *
 */

import it.unimi.dsi.lang.MutableString;

import java.io.IOException;
import java.io.Reader;
import java.io.Serializable;

/** A trivial {@link it.unimi.dsi.io.WordReader} that considers each line
 * of a document a single word.
 *
 * The intended usage of this class is that of indexing stuff like lists of document
 * identifiers: if the identifiers contain nonalphabetical characters, the default
 * {@link it.unimi.dsi.io.FastBufferedReader} might do a poor job.
 *
 * Note that the non-word returned by {@link #next(MutableString, MutableString)} is
 * always empty.
 */

public class LineWordReader implements WordReader, Serializable {
	private static final long serialVersionUID = 1L;
	/** An fast buffered reader wrapping the underlying reader. */
	private FastBufferedReader fastBufferedReader = new FastBufferedReader();

	@Override
	public boolean next(final MutableString word, final MutableString nonWord) throws IOException {
		nonWord.length(0);
		return fastBufferedReader.readLine(word) != null;
	}

	@Override
	public LineWordReader setReader(final Reader reader) {
		fastBufferedReader.setReader(reader);
		return this;
	}

	@Override
	public LineWordReader copy() {
		return new LineWordReader();
	}
}