library/log4php/renderers/LoggerRendererMap.php
changeset 46 f11c31f7fa3e
parent 45 a56e7f9a0463
child 47 03388ec805b4
equal deleted inserted replaced
45:a56e7f9a0463 46:f11c31f7fa3e
     1 <?php
       
     2 /**
       
     3  * Licensed to the Apache Software Foundation (ASF) under one or more
       
     4  * contributor license agreements. See the NOTICE file distributed with
       
     5  * this work for additional information regarding copyright ownership.
       
     6  * The ASF licenses this file to You under the Apache License, Version 2.0
       
     7  * (the "License"); you may not use this file except in compliance with
       
     8  * the License. You may obtain a copy of the License at
       
     9  *
       
    10  *       http://www.apache.org/licenses/LICENSE-2.0
       
    11  *
       
    12  * Unless required by applicable law or agreed to in writing, software
       
    13  * distributed under the License is distributed on an "AS IS" BASIS,
       
    14  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
       
    15  * See the License for the specific language governing permissions and
       
    16  * limitations under the License.
       
    17  *
       
    18  * @package log4php
       
    19  */
       
    20 
       
    21 /**
       
    22  * Manages defined renderers and determines which renderer to use for a given
       
    23  * input.
       
    24  *
       
    25  * @version $Revision: 1394956 $
       
    26  * @package log4php
       
    27  * @subpackage renderers
       
    28  * @since 0.3
       
    29  */
       
    30 class LoggerRendererMap {
       
    31 
       
    32     /**
       
    33      * Maps class names to appropriate renderers.
       
    34      * @var array
       
    35      */
       
    36     private $map = array();
       
    37 
       
    38     /**
       
    39      * The default renderer to use if no specific renderer is found.
       
    40      * @var LoggerRenderer
       
    41      */
       
    42     private $defaultRenderer;
       
    43 
       
    44     public function __construct() {
       
    45 
       
    46         // Set default config
       
    47         $this->reset();
       
    48     }
       
    49 
       
    50     /**
       
    51      * Adds a renderer to the map.
       
    52      *
       
    53      * If a renderer already exists for the given <var>$renderedClass</var> it
       
    54      * will be overwritten without warning.
       
    55      *
       
    56      * @param string $renderedClass The name of the class which will be
       
    57      *        rendered by the renderer.
       
    58      * @param string $renderingClass The name of the class which will
       
    59      *        perform the rendering.
       
    60      */
       
    61     public function addRenderer($renderedClass, $renderingClass) {
       
    62         // Check the rendering class exists
       
    63         if (!class_exists($renderingClass)) {
       
    64             trigger_error("log4php: Failed adding renderer. Rendering class [$renderingClass] not found.");
       
    65             return;
       
    66         }
       
    67 
       
    68         // Create the instance
       
    69         $renderer = new $renderingClass();
       
    70 
       
    71         // Check the class implements the right interface
       
    72         if (!($renderer instanceof LoggerRenderer)) {
       
    73             trigger_error("log4php: Failed adding renderer. Rendering class [$renderingClass] does not implement the LoggerRenderer interface.");
       
    74             return;
       
    75         }
       
    76 
       
    77         // Convert to lowercase since class names in PHP are not case sensitive
       
    78         $renderedClass = strtolower($renderedClass);
       
    79 
       
    80         $this->map[$renderedClass] = $renderer;
       
    81     }
       
    82 
       
    83     /**
       
    84      * Sets a custom default renderer class.
       
    85      *
       
    86      * TODO: there's code duplication here. This method is almost identical to
       
    87      * addRenderer(). However, it has custom error messages so let it sit for
       
    88      * now.
       
    89      *
       
    90      * @param string $renderingClass The name of the class which will
       
    91      *        perform the rendering.
       
    92      */
       
    93     public function setDefaultRenderer($renderingClass) {
       
    94         // Check the class exists
       
    95         if (!class_exists($renderingClass)) {
       
    96             trigger_error("log4php: Failed setting default renderer. Rendering class [$renderingClass] not found.");
       
    97             return;
       
    98         }
       
    99 
       
   100         // Create the instance
       
   101         $renderer = new $renderingClass();
       
   102 
       
   103         // Check the class implements the right interface
       
   104         if (!($renderer instanceof LoggerRenderer)) {
       
   105             trigger_error("log4php: Failed setting default renderer. Rendering class [$renderingClass] does not implement the LoggerRenderer interface.");
       
   106             return;
       
   107         }
       
   108 
       
   109         $this->defaultRenderer = $renderer;
       
   110     }
       
   111 
       
   112     /**
       
   113      * Returns the default renderer.
       
   114      * @var LoggerRenderer
       
   115      */
       
   116     public function getDefaultRenderer() {
       
   117         return $this->defaultRenderer;
       
   118     }
       
   119 
       
   120     /**
       
   121      * Finds the appropriate renderer for the given <var>input</var>, and
       
   122      * renders it (i.e. converts it to a string).
       
   123      *
       
   124      * @param mixed $input Input to render.
       
   125      * @return string The rendered contents.
       
   126      */
       
   127     public function findAndRender($input) {
       
   128         if ($input === null) {
       
   129             return null;
       
   130         }
       
   131 
       
   132         // For objects, try to find a renderer in the map
       
   133         if (is_object($input)) {
       
   134             $renderer = $this->getByClassName(get_class($input));
       
   135             if (isset($renderer)) {
       
   136                 return $renderer->render($input);
       
   137             }
       
   138         }
       
   139 
       
   140         // Fall back to the default renderer
       
   141         return $this->defaultRenderer->render($input);
       
   142     }
       
   143 
       
   144     /**
       
   145      * Returns the appropriate renderer for a given object.
       
   146      *
       
   147      * @param mixed $object
       
   148      * @return LoggerRenderer Or null if none found.
       
   149      */
       
   150     public function getByObject($object) {
       
   151         if (!is_object($object)) {
       
   152             return null;
       
   153         }
       
   154         return $this->getByClassName(get_class($object));
       
   155     }
       
   156 
       
   157     /**
       
   158      * Returns the appropriate renderer for a given class name.
       
   159      *
       
   160      * If no renderer could be found, returns NULL.
       
   161      *
       
   162      * @param string $class
       
   163      * @return LoggerRendererObject Or null if not found.
       
   164      */
       
   165     public function getByClassName($class) {
       
   166         for (; !empty($class); $class = get_parent_class($class)) {
       
   167             $class = strtolower($class);
       
   168             if (isset($this->map[$class])) {
       
   169                 return $this->map[$class];
       
   170             }
       
   171         }
       
   172         return null;
       
   173     }
       
   174 
       
   175     /** Empties the renderer map. */
       
   176     public function clear() {
       
   177         $this->map = array();
       
   178     }
       
   179 
       
   180     /** Resets the renderer map to it's default configuration. */
       
   181     public function reset() {
       
   182         $this->defaultRenderer = new LoggerRendererDefault();
       
   183         $this->clear();
       
   184         $this->addRenderer('Exception', 'LoggerRendererException');
       
   185     }
       
   186 }