/*
 * Copyright 2001-2004 The Apache Software Foundation
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package org.apache.commons.net;
import java.io.IOException;
import java.io.InputStream;

/***
 * The WhoisClient class implements the client side of the Internet Whois
 * Protocol defined in RFC 954.   To query a host you create a
 * WhoisClient instance, connect to the host, query the host, and finally
 * disconnect from the host.  If the whois service you want to query is on
 * a non-standard port, connect to the host at that port.
 * Here's a sample use:
 * <pre>
 *    WhoisClient whois;
 *
 *    whois = new WhoisClient();
 *
 *    try {
 *      whois.connect(WhoisClient.DEFAULT_HOST);
 *      System.out.println(whois.query("foobar"));
 *      whois.disconnect();
 *    } catch(IOException e) {
 *      System.err.println("Error I/O exception: " + e.getMessage());
 *      return;
 *    }
 * </pre>
 *
 * <p>
 * <p>
 * @author Daniel F. Savarese
 ***/

public final class WhoisClient extends FingerClient
{
    /***
     * The default whois host to query.  It is set to whois.internic.net.
     ***/
    public static final String DEFAULT_HOST = "whois.internic.net";

    /***
     * The default whois port.  It is set to 43 according to RFC 954.
     ***/
    public static final int DEFAULT_PORT = 43;


    /***
     * The default whois constructor.    Initializes the
     * default port to <code> DEFAULT_PORT </code>.
     ***/
    public WhoisClient()
    {
        setDefaultPort(DEFAULT_PORT);
    }

    /***
     * Queries the connected whois server for information regarding
     * the given handle.  It is up to the programmer to be familiar with the
     * handle syntax of the whois server.  You must first connect to a whois
     * server before calling this method, and you should disconnect afterward.
     * <p>
     * @param handle  The handle to lookup.
     * @return The result of the whois query.
     * @exception IOException  If an I/O error occurs during the operation.
     ***/
    public String query(String handle) throws IOException
    {
        return query(false, handle);
    }


    /***
     * Queries the connected whois server for information regarding
     * the given handle and returns the InputStream of the network connection.
     * It is up to the programmer to be familiar with the handle syntax
     * of the whois server.  You must first connect to a finger server before
     * calling this method, and you should disconnect after finishing reading
     * the stream.
     * <p>
     * @param handle  The handle to lookup.
     * @return The InputStream of the network connection of the whois query.
     *         Can be read to obtain whois results.
     * @exception IOException  If an I/O error occurs during the operation.
     ***/
    public InputStream getInputStream(String handle) throws IOException
    {
        return getInputStream(false, handle);
    }

}