diff --git a/library/log4php/LoggerNDC.php b/library/log4php/LoggerNDC.php deleted file mode 100644 --- a/library/log4php/LoggerNDC.php +++ /dev/null @@ -1,203 +0,0 @@ -<?php -/** - * 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 log4php - */ - -/** - * The NDC class implements <i>nested diagnostic contexts</i>. - * - * NDC was defined by Neil Harrison in the article "Patterns for Logging - * Diagnostic Messages" part of the book <i>"Pattern Languages of - * Program Design 3"</i> edited by Martin et al. - * - * A Nested Diagnostic Context, or NDC in short, is an instrument - * to distinguish interleaved log output from different sources. Log - * output is typically interleaved when a server handles multiple - * clients near-simultaneously. - * - * This class is similar to the {@link LoggerMDC} class except that it is - * based on a stack instead of a map. - * - * Interleaved log output can still be meaningful if each log entry - * from different contexts had a distinctive stamp. This is where NDCs - * come into play. - * - * <b>Note that NDCs are managed on a per thread basis</b>. - * - * NDC operations such as {@link push()}, {@link pop()}, - * {@link clear()}, {@link getDepth()} and {@link setMaxDepth()} - * affect the NDC of the <i>current</i> thread only. NDCs of other - * threads remain unaffected. - * - * For example, a servlet can build a per client request NDC - * consisting the clients host name and other information contained in - * the the request. <i>Cookies</i> are another source of distinctive - * information. To build an NDC one uses the {@link push()} - * operation. - * - * Simply put, - * - * - Contexts can be nested. - * - When entering a context, call <kbd>LoggerNDC::push()</kbd> - * As a side effect, if there is no nested diagnostic context for the - * current thread, this method will create it. - * - When leaving a context, call <kbd>LoggerNDC::pop()</kbd> - * - <b>When exiting a thread make sure to call {@link remove()}</b> - * - * There is no penalty for forgetting to match each - * <kbd>push</kbd> operation with a corresponding <kbd>pop</kbd>, - * except the obvious mismatch between the real application context - * and the context set in the NDC. - * - * If configured to do so, {@link LoggerPatternLayout} and {@link LoggerLayoutTTCC} - * instances automatically retrieve the nested diagnostic - * context for the current thread without any user intervention. - * Hence, even if a servlet is serving multiple clients - * simultaneously, the logs emanating from the same code (belonging to - * the same category) can still be distinguished because each client - * request will have a different NDC tag. - * - * Example: - * - * {@example ../../examples/php/ndc.php 19}<br> - * - * With the properties file: - * - * {@example ../../examples/resources/ndc.properties 18}<br> - * - * Will result in the following (notice the conn and client ids): - * - * <pre> - * 2009-09-13 19:04:27 DEBUG root conn=1234: just received a new connection in src/examples/php/ndc.php at 23 - * 2009-09-13 19:04:27 DEBUG root conn=1234 client=ab23: some more messages that can in src/examples/php/ndc.php at 25 - * 2009-09-13 19:04:27 DEBUG root conn=1234 client=ab23: now related to a client in src/examples/php/ndc.php at 26 - * 2009-09-13 19:04:27 DEBUG root : back and waiting for new connections in src/examples/php/ndc.php at 29 - * </pre> - * - * @version $Revision: 1350602 $ - * @package log4php - * @since 0.3 - */ -class LoggerNDC { - - /** This is the repository of NDC stack */ - private static $stack = array(); - - /** - * Clear any nested diagnostic information if any. This method is - * useful in cases where the same thread can be potentially used - * over and over in different unrelated contexts. - * - * <p>This method is equivalent to calling the {@link setMaxDepth()} - * method with a zero <var>maxDepth</var> argument. - */ - public static function clear() { - self::$stack = array(); - } - - /** - * Never use this method directly, use the {@link LoggerLoggingEvent::getNDC()} method instead. - * @return array - */ - public static function get() { - return implode(' ', self::$stack); - } - - /** - * Get the current nesting depth of this diagnostic context. - * - * @see setMaxDepth() - * @return integer - */ - public static function getDepth() { - return count(self::$stack); - } - - /** - * Clients should call this method before leaving a diagnostic - * context. - * - * <p>The returned value is the value that was pushed last. If no - * context is available, then the empty string "" is returned.</p> - * - * @return string The innermost diagnostic context. - */ - public static function pop() { - if (count(self::$stack) > 0) { - return array_pop(self::$stack); - } else { - return ''; - } - } - - /** - * Looks at the last diagnostic context at the top of this NDC - * without removing it. - * - * <p>The returned value is the value that was pushed last. If no - * context is available, then the empty string "" is returned.</p> - * @return string The innermost diagnostic context. - */ - public static function peek() { - if (count(self::$stack) > 0) { - return end(self::$stack); - } else { - return ''; - } - } - - /** - * Push new diagnostic context information for the current thread. - * - * <p>The contents of the <var>message</var> parameter is - * determined solely by the client. - * - * @param string $message The new diagnostic context information. - */ - public static function push($message) { - array_push(self::$stack, (string)$message); - } - - /** - * Remove the diagnostic context for this thread. - */ - public static function remove() { - LoggerNDC::clear(); - } - - /** - * Set maximum depth of this diagnostic context. If the current - * depth is smaller or equal to <var>maxDepth</var>, then no - * action is taken. - * - * <p>This method is a convenient alternative to multiple - * {@link pop()} calls. Moreover, it is often the case that at - * the end of complex call sequences, the depth of the NDC is - * unpredictable. The {@link setMaxDepth()} method circumvents - * this problem. - * - * @param integer $maxDepth - * @see getDepth() - */ - public static function setMaxDepth($maxDepth) { - $maxDepth = (int)$maxDepth; - if (LoggerNDC::getDepth() > $maxDepth) { - self::$stack = array_slice(self::$stack, 0, $maxDepth); - } - } -}