IMAPReply.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.imap;
import java.io.IOException;
import java.util.regex.Matcher;
import java.util.regex.Pattern;
import org.apache.commons.net.MalformedServerReplyException;
/**
* Stores IMAP reply code constants.
*/
public final class IMAPReply {
/** The reply code indicating success of an operation. */
public static final int OK = 0;
/** The reply code indicating failure of an operation. */
public static final int NO = 1;
/** The reply code indicating command rejection. */
public static final int BAD = 2;
/** The reply code indicating command continuation. */
public static final int CONT = 3;
/**
* 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
* on return.
*
* @since 3.4
*/
public static final int PARTIAL = 3;
/** The IMAP reply String indicating success of an operation. */
private static final String IMAP_OK = "OK";
/** The IMAP reply String indicating failure of an operation. */
private static final String IMAP_NO = "NO";
/** The IMAP reply String indicating command rejection. */
private static final String IMAP_BAD = "BAD";
// Start of line for untagged replies
private static final String IMAP_UNTAGGED_PREFIX = "* ";
// Start of line for continuation replies
private static final String IMAP_CONTINUATION_PREFIX = "+";
/**
* Guard against Polynomial regular expression used on uncontrolled data.
*
* Don't look for more than 80 letters.
* Don't look for more than 80 non-whitespace.
* Don't look for more than 80 character.
*/
private static final String TAGGED_RESPONSE = "^\\w{1,80} (\\S{1,80}).{0,80}";
/**
* Tag cannot contain: + ( ) { SP CTL % * " \ ]
*/
private static final Pattern TAGGED_PATTERN = Pattern.compile(TAGGED_RESPONSE);
/**
* Guard against Polynomial regular expression used on uncontrolled data.
*
* Don't look for more than 80 backslashes.
* Don't look for more than 80 character.
*/
private static final String UNTAGGED_RESPONSE = "^\\* (\\S{1,80}).{0,160}";
private static final Pattern UNTAGGED_PATTERN = Pattern.compile(UNTAGGED_RESPONSE);
private static final Pattern LITERAL_PATTERN = Pattern.compile("\\{(\\d+)\\}$"); // {dd}
/**
* Interpret the String reply code - OK, NO, BAD - in a tagged response as an integer.
*
* @param line the tagged line to be checked
* @return {@link #OK} or {@link #NO} or {@link #BAD} or {@link #CONT}
* @throws IOException if the input has an unexpected format
*/
public static int getReplyCode(final String line) throws IOException {
return getReplyCode(line, TAGGED_PATTERN);
}
// Helper method to process both tagged and untagged replies.
private static int getReplyCode(final String line, final Pattern pattern) throws IOException {
if (isContinuation(line)) {
return CONT;
}
final Matcher m = pattern.matcher(line);
if (m.matches()) { // TODO would lookingAt() be more efficient? If so, then drop trailing .* from patterns
final String code = m.group(1);
if (code.equals(IMAP_OK)) {
return OK;
}
if (code.equals(IMAP_BAD)) {
return BAD;
}
if (code.equals(IMAP_NO)) {
return NO;
}
}
throw new MalformedServerReplyException("Received unexpected IMAP protocol response from server: '" + line + "'.");
}
/**
* Interpret the String reply code - OK, NO, BAD - in an untagged response as an integer.
*
* @param line the untagged line to be checked
* @return {@link #OK} or {@link #NO} or {@link #BAD} or {@link #CONT}
* @throws IOException if the input has an unexpected format
*/
public static int getUntaggedReplyCode(final String line) throws IOException {
return getReplyCode(line, UNTAGGED_PATTERN);
}
/**
* Tests whether the reply line is a continuation, i.e. starts with "+"
*
* @param replyCode the code to be checked
* @return {@code true} if the response was a continuation
*/
public static boolean isContinuation(final int replyCode) {
return replyCode == CONT;
}
/**
* Tests whether if the reply line is a continuation, i.e. starts with "+"
*
* @param line the line to be checked
* @return {@code true} if the line is a continuation
*/
public static boolean isContinuation(final String line) {
return line.startsWith(IMAP_CONTINUATION_PREFIX);
}
/**
* Tests whether whether the reply code indicates success or not
*
* @param replyCode the code to check
* @return {@code true} if the code equals {@link #OK}
*/
public static boolean isSuccess(final int replyCode) {
return replyCode == OK;
}
/**
* Tests whether if the reply line is untagged - e.g. "* OK ..."
*
* @param line to be checked
* @return {@code true} if the line is untagged
*/
public static boolean isUntagged(final String line) {
return line.startsWith(IMAP_UNTAGGED_PREFIX);
}
/**
* Checks if the line introduces a literal, i.e. ends with {dd}
*
* @param line the line to check
* @return the literal count, or -1 if there was no literal.
*/
public static int literalCount(final String line) {
final Matcher m = LITERAL_PATTERN.matcher(line);
if (m.find()) {
return Integer.parseInt(m.group(1)); // Should always parse because we matched \d+
}
return -1;
}
/** Cannot be instantiated. */
private IMAPReply() {
}
}