commons-net.jar is the bytecode of Apache Commons Net library, which implements the client side of many basic Internet protocols.

Apache Commons Net Source Code files are provided in the binary packge (commons-net-3.8.0-bin.zip). You can download it at Apache Commons Net Website.

The source code of commons-net-3.8.0.jar is provided below:

⏎ org/apache/commons/net/nntp/Article.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.nntp;

import java.io.PrintStream;
import java.util.ArrayList;
import java.util.Collections;

import org.apache.commons.net.util.NetConstants;

/**
 * This is a class that contains the basic state needed for message retrieval and threading.
 * With thanks to Jamie  Zawinski (jwz@jwz.org)
 */
public class Article implements Threadable {
    private long articleNumber;
    private String subject;
    private String date;
    private String articleId;
    private String simplifiedSubject;
    private String from;
    private ArrayList<String> references;
    private boolean isReply;

    public Article kid, next;

    public Article() {
        articleNumber = -1; // isDummy
    }
    /**
     * Adds a message-id to the list of messages that this message references (i.e. replies to)
     * @param msgId the message id to add
     */
    public void addReference(final String msgId) {
        if (msgId == null || msgId.isEmpty()) {
            return;
        }
        if (references == null) {
            references = new ArrayList<>();
        }
        isReply = true;
        Collections.addAll(references, msgId.split(" "));
    }

    /**
     * Returns the MessageId references as an array of Strings
     * @return an array of message-ids
     */
    public String[] getReferences() {
        if (references == null) {
            return NetConstants.EMPTY_STRING_ARRAY;
        }
        return references.toArray(NetConstants.EMPTY_STRING_ARRAY);
    }

    /**
     * Attempts to parse the subject line for some typical reply signatures, and strip them out
     *
     */
    private void simplifySubject() {
            int start = 0;
            final String subject = getSubject();
            final int len = subject.length();

            boolean done = false;

            while (!done) {
                done = true;

                // skip whitespace
                // "Re: " breaks this
                while (start < len && subject.charAt(start) == ' ') {
                    start++;
                }

                if (start < (len - 2)
                    && (subject.charAt(start) == 'r' || subject.charAt(start) == 'R')
                    && (subject.charAt(start + 1) == 'e' || subject.charAt(start + 1) == 'E')) {

                    if (subject.charAt(start + 2) == ':') {
                        start += 3; // Skip "Re:"
                        done = false;
                    } else if (
                        start < (len - 2)
                        &&
                        (subject.charAt(start + 2) == '[' || subject.charAt(start + 2) == '(')) {

                        int i = start + 3;

                        while (i < len && subject.charAt(i) >= '0' && subject.charAt(i) <= '9') {
                            i++;
                        }

                        if (i < (len - 1)
                            && (subject.charAt(i) == ']' || subject.charAt(i) == ')')
                            && subject.charAt(i + 1) == ':')
                        {
                            start = i + 2;
                            done = false;
                        }
                    }
                }

                if ("(no subject)".equals(simplifiedSubject)) {
                    simplifiedSubject = "";
                }

                int end = len;

                while (end > start && subject.charAt(end - 1) < ' ') {
                    end--;
                }

                if (start == 0 && end == len) {
                    simplifiedSubject = subject;
                } else {
                    simplifiedSubject = subject.substring(start, end);
                }
            }
        }

    /**
     * Recursive method that traverses a pre-threaded graph (or tree)
     * of connected Article objects and prints them out.
     * @param article the root of the article 'tree'
     * @since 3.4
     */
    public static void printThread(final Article article) {
        printThread(article, 0, System.out);
    }

    /**
     * Recursive method that traverses a pre-threaded graph (or tree)
     * of connected Article objects and prints them out.
     * @param article the root of the article 'tree'
     * @param ps the PrintStream to use
     * @since 3.4
     */
    public static void printThread(final Article article, final PrintStream ps) {
        printThread(article, 0, ps);
    }

    /**
     * Recursive method that traverses a pre-threaded graph (or tree)
     * of connected Article objects and prints them out.
     * @param article the root of the article 'tree'
     * @param depth the current tree depth
     */
    public static void printThread(final Article article, final int depth) {
        printThread(article, depth, System.out);
    }

    /**
     * Recursive method that traverses a pre-threaded graph (or tree)
     * of connected Article objects and prints them out.
     * @param article the root of the article 'tree'
     * @param depth the current tree depth
     * @param ps the PrintStream to use
     * @since 3.4
     */
    public static void printThread(final Article article, final int depth, final PrintStream ps) {
            for (int i = 0; i < depth; ++i) {
                ps.print("==>");
            }
            ps.println(article.getSubject() + "\t" + article.getFrom()+"\t"+article.getArticleId());
            if (article.kid != null) {
                printThread(article.kid, depth + 1);
            }
            if (article.next != null) {
                printThread(article.next, depth);
            }
    }

    public String getArticleId() {
        return articleId;
    }

    public long getArticleNumberLong() {
        return articleNumber;
    }

    public String getDate() {
        return date;
    }

    public String getFrom() {
        return from;
    }

    public String getSubject() {
        return subject;
    }

    public void setArticleId(final String string) {
        articleId = string;
    }

    public void setArticleNumber(final long l) {
        articleNumber = l;
    }

    public void setDate(final String string) {
        date = string;
    }

    public void setFrom(final String string) {
        from = string;
    }

    public void setSubject(final String string) {
        subject = string;
    }


    @Override
    public boolean isDummy() {
        return (articleNumber == -1);
    }

    @Override
    public String messageThreadId() {
        return articleId;
    }

    @Override
    public String[] messageThreadReferences() {
        return getReferences();
    }

    @Override
    public String simplifiedSubject() {
        if(simplifiedSubject == null) {
            simplifySubject();
        }
        return simplifiedSubject;
    }


    @Override
    public boolean subjectIsReply() {
        return isReply;
    }


    @Override
    public void setChild(final Threadable child) {
        this.kid = (Article) child;
        flushSubjectCache();
    }

    private void flushSubjectCache() {
        simplifiedSubject = null;
    }


    @Override
    public void setNext(final Threadable next) {
        this.next = (Article)next;
        flushSubjectCache();
    }


    @Override
    public Threadable makeDummy() {
        return new Article();
    }

    @Override
    public String toString(){ // Useful for Eclipse debugging
        return articleNumber + " " +articleId + " " + subject;
    }

    // DEPRECATED METHODS - for API compatibility only - DO NOT USE

    @Deprecated
    public int getArticleNumber() {
        return (int) articleNumber;
    }

    @Deprecated
    public void setArticleNumber(final int a) {
        articleNumber = a;
    }
    @Deprecated

    public void addHeaderField(final String name, final String val) {
    }

}

⏎ org/apache/commons/net/nntp/Article.java

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File name: commons-net-3.8.0-sources.jar
File size: 437325 bytes
Release date: 2020-01-22
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