001/*
002 * Licensed to the Apache Software Foundation (ASF) under one or more
003 * contributor license agreements.  See the NOTICE file distributed with
004 * this work for additional information regarding copyright ownership.
005 * The ASF licenses this file to You under the Apache License, Version 2.0
006 * (the "License"); you may not use this file except in compliance with
007 * the License.  You may obtain a copy of the License at
008 *
009 *      https://www.apache.org/licenses/LICENSE-2.0
010 *
011 * Unless required by applicable law or agreed to in writing, software
012 * distributed under the License is distributed on an "AS IS" BASIS,
013 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
014 * See the License for the specific language governing permissions and
015 * limitations under the License.
016 */
017
018package org.apache.commons.net.daytime;
019
020import java.io.IOException;
021
022import org.apache.commons.io.IOUtils;
023import org.apache.commons.net.SocketClient;
024
025/**
026 * The DaytimeTCPClient class is a TCP implementation of a client for the Daytime protocol described in RFC 867. To use the class, merely establish a connection
027 * with {@link org.apache.commons.net.SocketClient#connect connect} and call {@link #getTime getTime()} to retrieve the daytime string, then call
028 * {@link org.apache.commons.net.SocketClient#disconnect disconnect} to close the connection properly.
029 *
030 * @see DaytimeUDPClient
031 */
032public final class DaytimeTCPClient extends SocketClient {
033
034    /**
035     * The default daytime port {@value} per RFC 867.
036     */
037    public static final int DEFAULT_PORT = 13;
038
039    /**
040     * The default DaytimeTCPClient constructor. It merely sets the default port to <code>DEFAULT_PORT</code>.
041     */
042    public DaytimeTCPClient() {
043        setDefaultPort(DEFAULT_PORT);
044    }
045
046    /**
047     * Gets the time string from the server and returns it. The server will have closed the connection at this point, so you should call
048     * {@link org.apache.commons.net.SocketClient#disconnect disconnect} after calling this method. To retrieve another time, you must initiate another
049     * connection with {@link org.apache.commons.net.SocketClient#connect connect} before calling {@code getTime()} again.
050     *
051     * @return The time string retrieved from the server.
052     * @throws IOException If an error occurs while fetching the time string.
053     */
054    public String getTime() throws IOException {
055        return IOUtils.toString(_input_, getCharset());
056    }
057
058}