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+<?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
+ */
+
+/**
+ * This class is specialized in retrieving loggers by name and also maintaining
+ * the logger hierarchy. The logger hierarchy is dealing with the several Log-Levels
+ * Logger can have. From log4j website:
+ *
+ * "A logger is said to be an ancestor of another logger if its name followed
+ * by a dot is a prefix of the descendant logger name. A logger is said to be
+ * a parent of a child logger if there are no ancestors between itself and the
+ * descendant logger."
+ *
+ * Child Loggers do inherit their Log-Levels from their Ancestors. They can
+ * increase their Log-Level compared to their Ancestors, but they cannot decrease it.
+ *
+ * <p>The casual user does not have to deal with this class directly.</p>
+ *
+ * <p>The structure of the logger hierarchy is maintained by the
+ * getLogger method. The hierarchy is such that children link
+ * to their parent but parents do not have any pointers to their
+ * children. Moreover, loggers can be instantiated in any order, in
+ * particular descendant before ancestor.</p>
+ *
+ * <p>In case a descendant is created before a particular ancestor,
+ * then it creates a provision node for the ancestor and adds itself
+ * to the provision node. Other descendants of the same ancestor add
+ * themselves to the previously created provision node.</p>
+ *
+ * @version $Revision: 1394956 $
+ * @package log4php
+ */
+class LoggerHierarchy {
+
+ /** Array holding all Logger instances. */
+ protected $loggers = array();
+
+ /**
+ * The root logger.
+ * @var RootLogger
+ */
+ protected $root;
+
+ /**
+ * The logger renderer map.
+ * @var LoggerRendererMap
+ */
+ protected $rendererMap;
+
+ /**
+ * Main level threshold. Events with lower level will not be logged by any
+ * logger, regardless of it's configuration.
+ * @var LoggerLevel
+ */
+ protected $threshold;
+
+ /**
+ * Creates a new logger hierarchy.
+ * @param LoggerRoot $root The root logger.
+ */
+ public function __construct(LoggerRoot $root) {
+ $this->root = $root;
+ $this->setThreshold(LoggerLevel::getLevelAll());
+ $this->rendererMap = new LoggerRendererMap();
+ }
+
+ /**
+ * Clears all loggers.
+ */
+ public function clear() {
+ $this->loggers = array();
+ }
+
+ /**
+ * Check if the named logger exists in the hierarchy.
+ * @param string $name
+ * @return boolean
+ */
+ public function exists($name) {
+ return isset($this->loggers[$name]);
+ }
+
+ /**
+ * Returns all the currently defined loggers in this hierarchy as an array.
+ * @return array
+ */
+ public function getCurrentLoggers() {
+ return array_values($this->loggers);
+ }
+
+ /**
+ * Returns a named logger instance logger. If it doesn't exist, one is created.
+ *
+ * @param string $name Logger name
+ * @return Logger Logger instance.
+ */
+ public function getLogger($name) {
+ if (!isset($this->loggers[$name])) {
+ $logger = new Logger($name);
+
+ $nodes = explode('.', $name);
+ $firstNode = array_shift($nodes);
+
+ // if name is not a first node but another first node is their
+ if ($firstNode != $name and isset($this->loggers[$firstNode])) {
+ $logger->setParent($this->loggers[$firstNode]);
+ } else {
+ // if there is no father, set root logger as father
+ $logger->setParent($this->root);
+ }
+
+ // if there are more nodes than one
+ if (count($nodes) > 0) {
+ // find parent node
+ foreach ($nodes as $node) {
+ $parentNode = "$firstNode.$node";
+ if (isset($this->loggers[$parentNode]) and $parentNode != $name) {
+ $logger->setParent($this->loggers[$parentNode]);
+ }
+ $firstNode .= ".$node";
+ }
+ }
+
+ $this->loggers[$name] = $logger;
+ }
+
+ return $this->loggers[$name];
+ }
+
+ /**
+ * Returns the logger renderer map.
+ * @return LoggerRendererMap
+ */
+ public function getRendererMap() {
+ return $this->rendererMap;
+ }
+
+ /**
+ * Returns the root logger.
+ * @return LoggerRoot
+ */
+ public function getRootLogger() {
+ return $this->root;
+ }
+
+ /**
+ * Returns the main threshold level.
+ * @return LoggerLevel
+ */
+ public function getThreshold() {
+ return $this->threshold;
+ }
+
+ /**
+ * Returns true if the hierarchy is disabled for given log level and false
+ * otherwise.
+ * @return boolean
+ */
+ public function isDisabled(LoggerLevel $level) {
+ return ($this->threshold->toInt() > $level->toInt());
+ }
+
+ /**
+ * Reset all values contained in this hierarchy instance to their
+ * default.
+ *
+ * This removes all appenders from all loggers, sets
+ * the level of all non-root loggers to <i>null</i>,
+ * sets their additivity flag to <i>true</i> and sets the level
+ * of the root logger to {@link LOGGER_LEVEL_DEBUG}.
+ *
+ * <p>Existing loggers are not removed. They are just reset.
+ *
+ * <p>This method should be used sparingly and with care as it will
+ * block all logging until it is completed.</p>
+ */
+ public function resetConfiguration() {
+ $root = $this->getRootLogger();
+
+ $root->setLevel(LoggerLevel::getLevelDebug());
+ $this->setThreshold(LoggerLevel::getLevelAll());
+ $this->shutDown();
+
+ foreach ($this->loggers as $logger) {
+ $logger->setLevel(null);
+ $logger->setAdditivity(true);
+ $logger->removeAllAppenders();
+ }
+
+ $this->rendererMap->reset();
+ LoggerAppenderPool::clear();
+ }
+
+ /**
+ * Sets the main threshold level.
+ * @param LoggerLevel $l
+ */
+ public function setThreshold(LoggerLevel $threshold) {
+ $this->threshold = $threshold;
+ }
+
+ /**
+ * Shutting down a hierarchy will <i>safely</i> close and remove
+ * all appenders in all loggers including the root logger.
+ *
+ * The shutdown method is careful to close nested
+ * appenders before closing regular appenders. This is allows
+ * configurations where a regular appender is attached to a logger
+ * and again to a nested appender.
+ *
+ * @todo Check if the last paragraph is correct.
+ */
+ public function shutdown() {
+ $this->root->removeAllAppenders();
+
+ foreach ($this->loggers as $logger) {
+ $logger->removeAllAppenders();
+ }
+ }
+
+ /**
+ * Prints the current Logger hierarchy tree. Useful for debugging.
+ */
+ public function printHierarchy() {
+ $this->printHierarchyInner($this->getRootLogger(), 0);
+ }
+
+ private function printHierarchyInner(Logger $current, $level) {
+ for ($i = 0; $i < $level; $i++) {
+ echo ($i == $level - 1) ? "|--" : "| ";
+ }
+ echo $current->getName() . "\n";
+
+ foreach ($this->loggers as $logger) {
+ if ($logger->getParent() == $current) {
+ $this->printHierarchyInner($logger, $level + 1);
+ }
+ }
+ }
+}