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You can browse JavaMail Source Code files below:

⏎ com/sun/mail/imap/DefaultFolder.java

/*
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER.
 *
 * Copyright (c) 1997-2018 Oracle and/or its affiliates. All rights reserved.
 *
 * The contents of this file are subject to the terms of either the GNU
 * General Public License Version 2 only ("GPL") or the Common Development
 * and Distribution License("CDDL") (collectively, the "License").  You
 * may not use this file except in compliance with the License.  You can
 * obtain a copy of the License at
 * https://oss.oracle.com/licenses/CDDL+GPL-1.1
 * or LICENSE.txt.  See the License for the specific
 * language governing permissions and limitations under the License.
 *
 * When distributing the software, include this License Header Notice in each
 * file and include the License file at LICENSE.txt.
 *
 * GPL Classpath Exception:
 * Oracle designates this particular file as subject to the "Classpath"
 * exception as provided by Oracle in the GPL Version 2 section of the License
 * file that accompanied this code.
 *
 * Modifications:
 * If applicable, add the following below the License Header, with the fields
 * enclosed by brackets [] replaced by your own identifying information:
 * "Portions Copyright [year] [name of copyright owner]"
 *
 * Contributor(s):
 * If you wish your version of this file to be governed by only the CDDL or
 * only the GPL Version 2, indicate your decision by adding "[Contributor]
 * elects to include this software in this distribution under the [CDDL or GPL
 * Version 2] license."  If you don't indicate a single choice of license, a
 * recipient has the option to distribute your version of this file under
 * either the CDDL, the GPL Version 2 or to extend the choice of license to
 * its licensees as provided above.  However, if you add GPL Version 2 code
 * and therefore, elected the GPL Version 2 license, then the option applies
 * only if the new code is made subject to such option by the copyright
 * holder.
 */

package com.sun.mail.imap;

import javax.mail.Folder;
import javax.mail.Message;
import javax.mail.MessagingException;
import javax.mail.MethodNotSupportedException;
import com.sun.mail.iap.ProtocolException;
import com.sun.mail.imap.protocol.IMAPProtocol;
import com.sun.mail.imap.protocol.ListInfo;

/**
 * The default IMAP folder (root of the naming hierarchy).
 *
 * @author  John Mani
 */

public class DefaultFolder extends IMAPFolder {
    
    protected DefaultFolder(IMAPStore store) {
	super("", UNKNOWN_SEPARATOR, store, null);
	exists = true; // of course
	type = HOLDS_FOLDERS; // obviously
    }

    @Override
    public synchronized String getName() {
	return fullName;
    }

    @Override
    public Folder getParent() {
	return null;
    }

    @Override
    public synchronized Folder[] list(final String pattern)
				throws MessagingException {
	ListInfo[] li = null;

	li = (ListInfo[])doCommand(new ProtocolCommand() {
	    @Override
	    public Object doCommand(IMAPProtocol p) throws ProtocolException {
		return p.list("", pattern);
	    }
	});

	if (li == null)
	    return new Folder[0];

	IMAPFolder[] folders = new IMAPFolder[li.length];
	for (int i = 0; i < folders.length; i++)
	    folders[i] = ((IMAPStore)store).newIMAPFolder(li[i]);
	return folders;
    }

    @Override
    public synchronized Folder[] listSubscribed(final String pattern)
				throws MessagingException {
	ListInfo[] li = null;

	li = (ListInfo[])doCommand(new ProtocolCommand() {
	    @Override
	    public Object doCommand(IMAPProtocol p) throws ProtocolException {
		return p.lsub("", pattern);
	    }
	});

	if (li == null)
	    return new Folder[0];

	IMAPFolder[] folders = new IMAPFolder[li.length];
	for (int i = 0; i < folders.length; i++)
	    folders[i] = ((IMAPStore)store).newIMAPFolder(li[i]);
	return folders;
    }

    @Override
    public boolean hasNewMessages() throws MessagingException {
	// Not applicable on DefaultFolder
	return false;
    }

    @Override
    public Folder getFolder(String name) throws MessagingException {
	return ((IMAPStore)store).newIMAPFolder(name, UNKNOWN_SEPARATOR);
    }

    @Override
    public boolean delete(boolean recurse) throws MessagingException {  
	// Not applicable on DefaultFolder
	throw new MethodNotSupportedException("Cannot delete Default Folder");
    }

    @Override
    public boolean renameTo(Folder f) throws MessagingException {
	// Not applicable on DefaultFolder
	throw new MethodNotSupportedException("Cannot rename Default Folder");
    }

    @Override
    public void appendMessages(Message[] msgs) throws MessagingException {
	// Not applicable on DefaultFolder
	throw new MethodNotSupportedException("Cannot append to Default Folder");
    }

    @Override
    public Message[] expunge() throws MessagingException {
	// Not applicable on DefaultFolder
	throw new MethodNotSupportedException("Cannot expunge Default Folder");
    }
}

⏎ com/sun/mail/imap/DefaultFolder.java

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File size: 851487 bytes
Release date: 2018-08-29
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