    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 *      http://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 */
    017package org.apache.commons.net.finger;
    018
    019import java.io.BufferedReader;
    020import java.io.IOException;
    021import java.io.InputStream;
    022import java.io.InputStreamReader;
    023import java.io.BufferedOutputStream;
    024import java.io.DataOutputStream;
    025
    026import org.apache.commons.net.SocketClient;
    027import org.apache.commons.net.util.Charsets;
    028
    029/***
    030 * The FingerClient class implements the client side of the Internet Finger
    031 * Protocol defined in RFC 1288.  To finger a host you create a
    032 * FingerClient instance, connect to the host, query the host, and finally
    033 * disconnect from the host.  If the finger service you want to query is on
    034 * a non-standard port, connect to the host at that port.
    035 * Here's a sample use:
    036 * <pre>
    037 *    FingerClient finger;
    038 *
    039 *    finger = new FingerClient();
    040 *
    041 *    try {
    042 *      finger.connect("foo.bar.com");
    043 *      System.out.println(finger.query("foobar", false));
    044 *      finger.disconnect();
    045 *    } catch(IOException e) {
    046 *      System.err.println("Error I/O exception: " + e.getMessage());
    047 *      return;
    048 *    }
    049 * </pre>
    050 *
    051 ***/
    052
    053public class FingerClient extends SocketClient
    054{
    055    /***
    056     * The default FINGER port.  Set to 79 according to RFC 1288.
    057     ***/
    058    public static final int DEFAULT_PORT = 79;
    059
    060    private static final String __LONG_FLAG = "/W ";
    061
    062    private transient char[] __buffer = new char[1024];
    063
    064    /***
    065     * The default FingerClient constructor.  Initializes the
    066     * default port to <code> DEFAULT_PORT </code>.
    067     ***/
    068    public FingerClient()
    069    {
    070        setDefaultPort(DEFAULT_PORT);
    071    }
    072
    073
    074    /***
    075     * Fingers a user at the connected host and returns the output
    076     * as a String.  You must first connect to a finger server before
    077     * calling this method, and you should disconnect afterward.
    078     *
    079     * @param longOutput Set to true if long output is requested, false if not.
    080     * @param username  The name of the user to finger.
    081     * @return The result of the finger query.
    082     * @throws IOException If an I/O error occurs while reading the socket.
    083     ***/
    084    public String query(boolean longOutput, String username) throws IOException
    085    {
    086        int read;
    087        StringBuilder result = new StringBuilder(__buffer.length);
    088        BufferedReader input;
    089
    090        input =
    091            new BufferedReader(new InputStreamReader(getInputStream(longOutput,
    092                               username), getCharset()));
    093
    094        try {
    095            while (true)
    096            {
    097                read = input.read(__buffer, 0, __buffer.length);
    098                if (read <= 0) {
    099                    break;
    100                }
    101                result.append(__buffer, 0, read);
    102            }
    103        } finally {
    104            input.close();
    105        }
    106
    107        return result.toString();
    108    }
    109
    110
    111    /***
    112     * Fingers the connected host and returns the output
    113     * as a String.  You must first connect to a finger server before
    114     * calling this method, and you should disconnect afterward.
    115     * This is equivalent to calling <code> query(longOutput, "") </code>.
    116     *
    117     * @param longOutput Set to true if long output is requested, false if not.
    118     * @return The result of the finger query.
    119     * @throws IOException If an I/O error occurs while reading the socket.
    120     ***/
    121    public String query(boolean longOutput) throws IOException
    122    {
    123        return query(longOutput, "");
    124    }
    125
    126
    127    /***
    128     * Fingers a user and returns the input stream from the network connection
    129     * of the finger query.  You must first connect to a finger server before
    130     * calling this method, and you should disconnect after finishing reading
    131     * the stream.
    132     *
    133     * @param longOutput Set to true if long output is requested, false if not.
    134     * @param username  The name of the user to finger.
    135     * @return The InputStream of the network connection of the finger query.
    136     *         Can be read to obtain finger results.
    137     * @throws IOException If an I/O error during the operation.
    138     ***/
    139    public InputStream getInputStream(boolean longOutput, String username)
    140    throws IOException
    141    {
    142        return getInputStream(longOutput, username, null);
    143    }
    144
    145    /***
    146     * Fingers a user and returns the input stream from the network connection
    147     * of the finger query.  You must first connect to a finger server before
    148     * calling this method, and you should disconnect after finishing reading
    149     * the stream.
    150     *
    151     * @param longOutput Set to true if long output is requested, false if not.
    152     * @param username  The name of the user to finger.
    153     * @param encoding the character encoding that should be used for the query,
    154     *        null for the platform's default encoding
    155     * @return The InputStream of the network connection of the finger query.
    156     *         Can be read to obtain finger results.
    157     * @throws IOException If an I/O error during the operation.
    158     ***/
    159    public InputStream getInputStream(boolean longOutput, String username, String encoding)
    160    throws IOException
    161    {
    162        DataOutputStream output;
    163        StringBuilder buffer = new StringBuilder(64);
    164        if (longOutput) {
    165            buffer.append(__LONG_FLAG);
    166        }
    167        buffer.append(username);
    168        buffer.append(SocketClient.NETASCII_EOL);
    169
    170        // Note: Charsets.toCharset() returns the platform default for null input
    171        byte[] encodedQuery = buffer.toString().getBytes(Charsets.toCharset(encoding).name()); // Java 1.6 can use charset directly
    172
    173        output = new DataOutputStream(new BufferedOutputStream(_output_, 1024));
    174        output.write(encodedQuery, 0, encodedQuery.length);
    175        output.flush();
    176
    177        return _input_;
    178    }
    179
    180
    181    /***
    182     * Fingers the connected host and returns the input stream from
    183     * the network connection of the finger query.  This is equivalent to
    184     * calling getInputStream(longOutput, "").  You must first connect to a
    185     * finger server before calling this method, and you should disconnect
    186     * after finishing reading the stream.
    187     *
    188     * @param longOutput Set to true if long output is requested, false if not.
    189     * @return The InputStream of the network connection of the finger query.
    190     *         Can be read to obtain finger results.
    191     * @throws IOException If an I/O error during the operation.
    192     ***/
    193    public InputStream getInputStream(boolean longOutput) throws IOException
    194    {
    195        return getInputStream(longOutput, "");
    196    }
    197
    198}