Commons Net example source code file (NewGroupsOrNewsQuery.java)

This example Commons Net source code file (NewGroupsOrNewsQuery.java) is included in the DevDaily.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" ^TM.

Java - Commons Net tags/keywords

newgroupsornewsquery, newgroupsornewsquery, string, string, stringbuffer, stringbuffer, stringbuilder, stringbuilder, util

The Commons Net NewGroupsOrNewsQuery.java source code

/*
 * 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.nntp;

import java.util.Calendar;

/***
 * The NewGroupsOrNewsQuery class.  This is used to issue NNTP NEWGROUPS and
 * NEWNEWS queries, implemented by
 * {@link org.apache.commons.net.nntp.NNTPClient#listNewNewsgroups listNewNewsGroups }
 *  and
 * {@link org.apache.commons.net.nntp.NNTPClient#listNewNews listNewNews }
 *  respectively.  It prevents you from having to format
 * date, time, distribution, and newgroup arguments.
 * <p>
 * You might use the class as follows:
 * <pre>
 * query = new NewsGroupsOrNewsQuery(new GregorianCalendar(97, 11, 15), false);
 * query.addDistribution("comp");
 * NewsgroupInfo[] newsgroups = client.listNewgroups(query);
 * </pre>
 * This will retrieve the list of newsgroups starting with the comp.
 * distribution prefix created since midnight 11/15/97.
 * <p>
 * <p>
 * @see NNTPClient
 ***/

public final class NewGroupsOrNewsQuery
{
    private String __date, __time;
    private StringBuffer __distributions;
    private StringBuffer __newsgroups;
    private boolean __isGMT;


    /***
     * Creates a new query using the given time as a reference point.
     * <p>
     * @param date  The date since which new groups or news have arrived.
     * @param gmt   True if the date should be considered as GMT, false if not.
     ***/
    public NewGroupsOrNewsQuery(Calendar date, boolean gmt)
    {
        int num;
        String str;
        StringBuilder buffer;

        __distributions = null;
        __newsgroups = null;
        __isGMT = gmt;

        buffer = new StringBuilder();

        // Get year
        num = date.get(Calendar.YEAR);
        str = Integer.toString(num);
        num = str.length();

        if (num >= 2)
            buffer.append(str.substring(num - 2));
        else
            buffer.append("00");

        // Get month
        num = date.get(Calendar.MONTH) + 1;
        str = Integer.toString(num);
        num = str.length();

        if (num == 1)
        {
            buffer.append('0');
            buffer.append(str);
        }
        else if (num == 2)
            buffer.append(str);
        else
            buffer.append("01");

        // Get day
        num = date.get(Calendar.DAY_OF_MONTH);
        str = Integer.toString(num);
        num = str.length();

        if (num == 1)
        {
            buffer.append('0');
            buffer.append(str);
        }
        else if (num == 2)
            buffer.append(str);
        else
            buffer.append("01");

        __date = buffer.toString();

        buffer.setLength(0);

        // Get hour
        num = date.get(Calendar.HOUR_OF_DAY);
        str = Integer.toString(num);
        num = str.length();

        if (num == 1)
        {
            buffer.append('0');
            buffer.append(str);
        }
        else if (num == 2)
            buffer.append(str);
        else
            buffer.append("00");

        // Get minutes
        num = date.get(Calendar.MINUTE);
        str = Integer.toString(num);
        num = str.length();

        if (num == 1)
        {
            buffer.append('0');
            buffer.append(str);
        }
        else if (num == 2)
            buffer.append(str);
        else
            buffer.append("00");


        // Get seconds
        num = date.get(Calendar.SECOND);
        str = Integer.toString(num);
        num = str.length();

        if (num == 1)
        {
            buffer.append('0');
            buffer.append(str);
        }
        else if (num == 2)
            buffer.append(str);
        else
            buffer.append("00");

        __time = buffer.toString();
    }


    /***
     * Add a newsgroup to the list of newsgroups being queried.  Newsgroups
     * added this way are only meaningful to the NEWNEWS command.  Newsgroup
     * names may include the <code> *  wildcard, as in
     * <code>comp.lang.*  or  comp.lang.java.* .  Adding
     * at least one newsgroup is mandatory for the NEWNEWS command.
     * <p>
     * @param newsgroup  The newsgroup to add to the list of groups to be
     *                   checked for new news.
     ***/
    public void addNewsgroup(String newsgroup)
    {
        if (__newsgroups != null)
            __newsgroups.append(',');
        else
            __newsgroups = new StringBuffer();
        __newsgroups.append(newsgroup);
    }


    /***
     * Add a newsgroup to the list of newsgroups being queried, but indicate
     * that group should not be checked for new news.  Newsgroups
     * added this way are only meaningful to the NEWNEWS command.
     * Newsgroup names may include the <code> *  wildcard, as in
     * <code>comp.lang.*  or  comp.lang.java.* .
     * <p>
     * The following would create a query that searched for new news in
     * all comp.lang.java newsgroups except for comp.lang.java.advocacy.
     * <pre>
     * query.addNewsgroup("comp.lang.java.*");
     * query.omitNewsgroup("comp.lang.java.advocacy");
     * </pre>
     * <p>
     * @param newsgroup  The newsgroup to add to the list of groups to be
     *                   checked for new news, but which should be omitted from
     *                   the search for new news..
     ***/
    public void omitNewsgroup(String newsgroup)
    {
        addNewsgroup("!" + newsgroup);
    }


    /***
     * Add a distribution group to the query.  The distribution part of a
     * newsgroup is the segment of the name preceding the first dot (e.g.,
     * comp, alt, rec).  Only those newsgroups matching one of the
     * distributions or, in the case of NEWNEWS, an article in a newsgroup
     * matching one of the distributions, will be reported as a query result.
     * Adding distributions is purely optional.
     * <p>
     * @param distribution A distribution to add to the query.
     ***/
    public void addDistribution(String distribution)
    {
        if (__distributions != null)
            __distributions.append(',');
        else
            __distributions = new StringBuffer();
        __distributions.append(distribution);
    }

    /***
     * Return the NNTP query formatted date (year, month, day in the form
     * YYMMDD.
     * <p>
     * @return The NNTP query formatted date.
     ***/
    public String getDate()
    {
        return __date;
    }

    /***
     * Return the NNTP query formatted time (hour, minutes, seconds in the form
     * HHMMSS.
     * <p>
     * @return The NNTP query formatted time.
     ***/
    public String getTime()
    {
        return __time;
    }

    /***
     * Return whether or not the query date should be treated as GMT.
     * <p>
     * @return True if the query date is to be treated as GMT, false if not.
     ***/
    public boolean isGMT()
    {
        return __isGMT;
    }

    /***
     * Return the comma separated list of distributions.  This may be null
     * if there are no distributions.
     * <p>
     * @return The list of distributions, which may be null if no distributions
     *         have been specified.
     ***/
    public String getDistributions()
    {
        return (__distributions == null ? null : __distributions.toString());
    }

    /***
     * Return the comma separated list of newsgroups.  This may be null
     * if there are no newsgroups
     * <p>
     * @return The list of newsgroups, which may be null if no newsgroups
     *         have been specified.
     ***/
    public String getNewsgroups()
    {
        return (__newsgroups == null ? null : __newsgroups.toString());
    }
}