ArticleReader.java

/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You 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.examples.nntp;

import java.io.BufferedReader;
import java.io.IOException;
import java.net.SocketException;

import org.apache.commons.net.PrintCommandListener;
import org.apache.commons.net.io.Util;
import org.apache.commons.net.nntp.NNTPClient;
import org.apache.commons.net.nntp.NewsgroupInfo;

/**
 * Sample program demonstrating the use of article header and body retrieval
 */
public class ArticleReader {

    public static void main(final String[] args) throws SocketException, IOException {

        if (args.length != 2 && args.length != 3 && args.length != 5) {
            System.out.println("Usage: MessageThreading <hostname> <groupname> [<article specifier> [<user> <password>]]");
            return;
        }

        final String hostname = args[0];
        final String newsgroup = args[1];
        // Article specifier can be numeric or Id in form <m.n.o.x@host>
        final String articleSpec = args.length >= 3 ? args[2] : null;

        final NNTPClient client = new NNTPClient();
        client.addProtocolCommandListener(new PrintCommandListener(Util.newPrintWriter(System.out), true));
        client.connect(hostname);

        if (args.length == 5) { // Optional auth
            final String user = args[3];
            final String password = args[4];
            if (!client.authenticate(user, password)) {
                System.out.println("Authentication failed for user " + user + "!");
                System.exit(1);
            }
        }

        final NewsgroupInfo group = new NewsgroupInfo();
        client.selectNewsgroup(newsgroup, group);

        final BufferedReader brHdr;
        String line;
        if (articleSpec != null) {
            brHdr = (BufferedReader) client.retrieveArticleHeader(articleSpec);
        } else {
            final long articleNum = group.getLastArticleLong();
            brHdr = client.retrieveArticleHeader(articleNum);
        }
        if (brHdr != null) {
            while ((line = brHdr.readLine()) != null) {
                System.out.println(line);
            }
            brHdr.close();
        }
        final BufferedReader brBody;
        if (articleSpec != null) {
            brBody = (BufferedReader) client.retrieveArticleBody(articleSpec);
        } else {
            final long articleNum = group.getLastArticleLong();
            brBody = client.retrieveArticleBody(articleNum);
        }
        if (brBody != null) {
            while ((line = brBody.readLine()) != null) {
                System.out.println(line);
            }
            brBody.close();
        }
    }

}