listcommand.java

java 开发的邮件服务器平台。支持以下协议。 协议可以修改为自己的专门标识

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 * Copyright (c) 2000-2004 The Apache Software Foundation.             *
 * All rights reserved.                                                *
 * ------------------------------------------------------------------- *
 * 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.                      *
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package org.apache.james.imapserver.commands;

import org.apache.james.imapserver.store.ImapMailbox;
import org.apache.james.imapserver.ImapRequestLineReader;
import org.apache.james.imapserver.ImapResponse;
import org.apache.james.imapserver.ImapSession;
import org.apache.james.imapserver.store.MailboxException;
import org.apache.james.imapserver.ProtocolException;
import org.apache.james.util.Assert;

import java.util.ArrayList;
import java.util.Collection;
import java.util.Iterator;

/**
 * Handles processeing for the LIST imap command.
 *
 *
 * @version $Revision: 1.3.2.3 $
 */
class ListCommand extends AuthenticatedStateCommand
{
    public static final String NAME = "LIST";
    public static final String ARGS = "<reference-name> <mailbox-name-with-wildcards>";

    private ListCommandParser parser = new ListCommandParser();

    /** @see CommandTemplate#doProcess */
    protected void doProcess( ImapRequestLineReader request,
                              ImapResponse response,
                              ImapSession session )
            throws ProtocolException, MailboxException
    {
        String referenceName = parser.mailbox( request );
        String mailboxPattern = parser.listMailbox( request );
        parser.endLine( request );

        // Should the #user.userName section be removed from names returned?
        boolean removeUserPrefix;

        Collection mailboxes;
        if ( mailboxPattern.length() == 0 ) {
            // An empty mailboxPattern signifies a request for the hierarchy delimiter
            // and root name of the referenceName argument

            String referenceRoot;
            if ( referenceName.startsWith( NAMESPACE_PREFIX ) )
            {
                // A qualified reference name - get the first element,
                // and don't remove the user prefix
                removeUserPrefix = false;
                int firstDelimiter = referenceName.indexOf( HIERARCHY_DELIMITER_CHAR );
                if ( firstDelimiter == -1 ) {
                    referenceRoot = referenceName;
                }
                else {
                    referenceRoot = referenceName.substring(0, firstDelimiter );
                }
            }
            else {
                // A relative reference name - need to remove user prefix from results.
                referenceRoot = "";
                removeUserPrefix = true;
            }

            // Get the mailbox for the reference name.
            ImapMailbox referenceMailbox = getMailbox( referenceRoot, session, false );

            // If it doesn't exist, act as though "" was passed for reference name.
            if ( referenceMailbox == null )
            {
                referenceMailbox = getMailbox( "", session, true );
                removeUserPrefix = true;
            }

            mailboxes = new ArrayList( 1 );
            mailboxes.add( referenceMailbox );
        }
        else {
            String searchPattern;

            // If the mailboxPattern is fully qualified, ignore the
            // reference name.
            if ( mailboxPattern.charAt( 0 ) == NAMESPACE_PREFIX_CHAR ) {
                searchPattern = mailboxPattern;
            }
            else {
                searchPattern = combineSearchTerms( referenceName, mailboxPattern );
            }

            // If the search pattern is relative, need to remove user prefix from results.
            removeUserPrefix = ( searchPattern.charAt(0) != NAMESPACE_PREFIX_CHAR );

            mailboxes = doList( session, searchPattern );
        }

        String personalNamespace = USER_NAMESPACE + HIERARCHY_DELIMITER_CHAR +
                session.getUser().getUserName();
        int prefixLength = personalNamespace.length();

        Iterator iterator = mailboxes.iterator();
        while ( iterator.hasNext() ) {
            ImapMailbox mailbox = ( ImapMailbox ) iterator.next();
            StringBuffer message = new StringBuffer( "(" );
            if ( !mailbox.isSelectable() ) {
                message.append( "\\Noselect" );
            }
            message.append( ") \"" );
            message.append( HIERARCHY_DELIMITER_CHAR );
            message.append( "\" " );

            String mailboxName = mailbox.getFullName();
            if ( removeUserPrefix ) {
                if ( mailboxName.length() <= prefixLength ) {
                    mailboxName = "";
                }
                else {
                    mailboxName = mailboxName.substring( prefixLength + 1 );
                }
            }

            // TODO: need to check if the mailbox name needs quoting.
            if ( mailboxName.length() == 0 ) {
                message.append("\"\"");
            }
            else {
                message.append( mailboxName );
            }

            response.commandResponse( this, message.toString() );
        }

        session.unsolicitedResponses( response );
        response.commandComplete( this );
    }

    protected Collection doList( ImapSession session, String searchPattern ) throws MailboxException
    {
        return session.getHost().listMailboxes( session.getUser(), searchPattern );
    }

    private String combineSearchTerms( String referenceName, String mailboxMatch )
    {
        Assert.isTrue( mailboxMatch.length() > 0 );

        // Otherwise, combine the referenceName and mailbox name.
        StringBuffer buffer = new StringBuffer( mailboxMatch );

        // Make sure the 2 strings are joined by only one HIERARCHY_DELIMITER_CHAR
        if ( referenceName.endsWith( HIERARCHY_DELIMITER ) ) {
            if ( buffer.charAt(0) == HIERARCHY_DELIMITER_CHAR ) {
                buffer.deleteCharAt( 0 );
            }
        }
        else {
            if ( buffer.charAt(0) != HIERARCHY_DELIMITER_CHAR ) {
                buffer.insert( 0, HIERARCHY_DELIMITER_CHAR );
            }
        }

        buffer.insert( 0, referenceName );
        return buffer.toString();
    }

    /** @see ImapCommand#getName */
    public String getName()
    {
        return NAME;
    }

    /** @see CommandTemplate#getArgSyntax */
    public String getArgSyntax()
    {
        return ARGS;
    }