    001/*
    002 * Licensed to the Apache Software Foundation (ASF) under one or more
    003 * contributor license agreements.  See the NOTICE file distributed with
    004 * this work for additional information regarding copyright ownership.
    005 * The ASF licenses this file to You under the Apache License, Version 2.0
    006 * (the "License"); you may not use this file except in compliance with
    007 * the License.  You may obtain a copy of the License at
    008 *
    009 *      http://www.apache.org/licenses/LICENSE-2.0
    010 *
    011 * Unless required by applicable law or agreed to in writing, software
    012 * distributed under the License is distributed on an "AS IS" BASIS,
    013 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    014 * See the License for the specific language governing permissions and
    015 * limitations under the License.
    016 */
    017
    018package org.apache.commons.net.imap;
    019
    020import java.io.IOException;
    021import java.util.regex.Matcher;
    022import java.util.regex.Pattern;
    023
    024import org.apache.commons.net.MalformedServerReplyException;
    025
    026/**
    027 * IMAPReply stores IMAP reply code constants.
    028 */
    029
    030public final class IMAPReply {
    031    /** The reply code indicating success of an operation. */
    032    public static final int OK = 0;
    033
    034    /** The reply code indicating failure of an operation. */
    035    public static final int NO = 1;
    036
    037    /** The reply code indicating command rejection. */
    038    public static final int BAD = 2;
    039
    040    /** The reply code indicating command continuation. */
    041    public static final int CONT = 3;
    042
    043    /**
    044     * The reply code indicating a partial response. This is used when a chunk listener is registered and the listener requests that the reply lines are cleared
    045     * on return.
    046     *
    047     * @since 3.4
    048     */
    049    public static final int PARTIAL = 3;
    050
    051    /** The IMAP reply String indicating success of an operation. */
    052    private static final String IMAP_OK = "OK";
    053
    054    /** The IMAP reply String indicating failure of an operation. */
    055    private static final String IMAP_NO = "NO";
    056
    057    /** The IMAP reply String indicating command rejection. */
    058    private static final String IMAP_BAD = "BAD";
    059
    060    // Start of line for untagged replies
    061    private static final String IMAP_UNTAGGED_PREFIX = "* ";
    062
    063    // Start of line for continuation replies
    064    private static final String IMAP_CONTINUATION_PREFIX = "+";
    065
    066    private static final String TAGGED_RESPONSE = "^\\w+ (\\S+).*"; // TODO perhaps be less strict on tag match?
    067
    068    // tag cannot contain: + ( ) { SP CTL % * " \ ]
    069    private static final Pattern TAGGED_PATTERN = Pattern.compile(TAGGED_RESPONSE);
    070
    071    private static final String UNTAGGED_RESPONSE = "^\\* (\\S+).*";
    072
    073    private static final Pattern UNTAGGED_PATTERN = Pattern.compile(UNTAGGED_RESPONSE);
    074    private static final Pattern LITERAL_PATTERN = Pattern.compile("\\{(\\d+)\\}$"); // {dd}
    075
    076    /**
    077     * Intepret the String reply code - OK, NO, BAD - in a tagged response as a integer.
    078     *
    079     * @param line the tagged line to be checked
    080     * @return {@link #OK} or {@link #NO} or {@link #BAD} or {@link #CONT}
    081     * @throws IOException if the input has an unexpected format
    082     */
    083    public static int getReplyCode(final String line) throws IOException {
    084        return getReplyCode(line, TAGGED_PATTERN);
    085    }
    086
    087    // Helper method to process both tagged and untagged replies.
    088    private static int getReplyCode(final String line, final Pattern pattern) throws IOException {
    089        if (isContinuation(line)) {
    090            return CONT;
    091        }
    092        final Matcher m = pattern.matcher(line);
    093        if (m.matches()) { // TODO would lookingAt() be more efficient? If so, then drop trailing .* from patterns
    094            final String code = m.group(1);
    095            if (code.equals(IMAP_OK)) {
    096                return OK;
    097            }
    098            if (code.equals(IMAP_BAD)) {
    099                return BAD;
    100            }
    101            if (code.equals(IMAP_NO)) {
    102                return NO;
    103            }
    104        }
    105        throw new MalformedServerReplyException("Received unexpected IMAP protocol response from server: '" + line + "'.");
    106    }
    107
    108    /**
    109     * Intepret the String reply code - OK, NO, BAD - in an untagged response as a integer.
    110     *
    111     * @param line the untagged line to be checked
    112     * @return {@link #OK} or {@link #NO} or {@link #BAD} or {@link #CONT}
    113     * @throws IOException if the input has an unexpected format
    114     */
    115    public static int getUntaggedReplyCode(final String line) throws IOException {
    116        return getReplyCode(line, UNTAGGED_PATTERN);
    117    }
    118
    119    /**
    120     * Checks if the reply line is a continuation, i.e. starts with "+"
    121     *
    122     * @param replyCode the code to be checked
    123     * @return {@code true} if the response was a continuation
    124     */
    125    public static boolean isContinuation(final int replyCode) {
    126        return replyCode == CONT;
    127    }
    128
    129    /**
    130     * Checks if the reply line is a continuation, i.e. starts with "+"
    131     *
    132     * @param line the line to be checked
    133     * @return {@code true} if the line is untagged
    134     */
    135    public static boolean isContinuation(final String line) {
    136        return line.startsWith(IMAP_CONTINUATION_PREFIX);
    137    }
    138
    139    /**
    140     * Checks whether the reply code indicates success or not
    141     *
    142     * @param replyCode the code to check
    143     * @return {@code true} if the code equals {@link #OK}
    144     */
    145    public static boolean isSuccess(final int replyCode) {
    146        return replyCode == OK;
    147    }
    148
    149    /**
    150     * Checks if the reply line is untagged - e.g. "* OK ..."
    151     *
    152     * @param line to be checked
    153     * @return {@code true} if the line is untagged
    154     */
    155    public static boolean isUntagged(final String line) {
    156        return line.startsWith(IMAP_UNTAGGED_PREFIX);
    157    }
    158
    159    /**
    160     * Checks if the line introduces a literal, i.e. ends with {dd}
    161     *
    162     * @param line the line to check
    163     *
    164     * @return the literal count, or -1 if there was no literal.
    165     */
    166    public static int literalCount(final String line) {
    167        final Matcher m = LITERAL_PATTERN.matcher(line);
    168        if (m.find()) {
    169            return Integer.parseInt(m.group(1)); // Should always parse because we matched \d+
    170        }
    171        return -1;
    172    }
    173
    174    // Cannot be instantiated.
    175    private IMAPReply() {
    176    }
    177
    178}
    179
    180/* kate: indent-width 4; replace-tabs on; */