Java tutorial
/* * ------------------------------------------------------------------------------ * Hermes FTP Server * Copyright (c) 2005-2014 Lars Behnke * ------------------------------------------------------------------------------ * * This file is part of Hermes FTP Server. * * Hermes FTP Server is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2 of the License, or * (at your option) any later version. * * Hermes FTP Server 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 General Public License for more details. * * You should have received a copy of the GNU General Public License * along with Hermes FTP Server; if not, write to the Free Software * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA * ------------------------------------------------------------------------------ */ package com.apporiented.hermesftp.utils; import java.io.BufferedReader; import java.io.IOException; import java.io.Reader; import org.apache.commons.logging.Log; import org.apache.commons.logging.LogFactory; /** * A writer that adds logging capability to a passed writer. This mechanism corresponds the * decorator pattern. * * @author Lars Behnke * */ public class LoggingReader extends BufferedReader { private static Log log = LogFactory.getLog(LoggingReader.class); private static final int LOG_LINE_LENGTH = 80; /** * Constructor. * * @param in A reader. */ public LoggingReader(Reader in) { super(in); } /** * Constructor. * * @param in A reader. * @param sz Input buffer size. */ public LoggingReader(Reader in, int sz) { super(in, sz); } /** * {@inheritDoc} */ public String readLine() throws IOException { String result = super.readLine(); if (log.isDebugEnabled()) { String x; if (result != null && result.length() >= LOG_LINE_LENGTH) { x = result.substring(0, LOG_LINE_LENGTH) + " [" + (result.length() - LOG_LINE_LENGTH) + " more chars]"; } else { x = result; } log.debug("<--: " + x); } return result; } }