diff --git a/library/log4php/helpers/LoggerPatternParser.php b/library/log4php/helpers/LoggerPatternParser.php
new file mode 100644
--- /dev/null
+++ b/library/log4php/helpers/LoggerPatternParser.php
@@ -0,0 +1,237 @@
+<?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
+ */
+
+/**
+ * Most of the work of the {@link LoggerPatternLayout} class
+ * is delegated to the {@link LoggerPatternParser} class.
+ *
+ * <p>It is this class that parses conversion patterns and creates
+ * a chained list of {@link LoggerPatternConverter} converters.</p>
+ *
+ * @version $Revision: 1395467 $
+ * @package log4php
+ * @subpackage helpers
+ *
+ * @since 0.3
+ */
+class LoggerPatternParser {
+
+    /** Escape character for conversion words in the conversion pattern. */
+    const ESCAPE_CHAR = '%';
+
+    /** Maps conversion words to relevant converters. */
+    private $converterMap;
+
+    /** Conversion pattern used in layout. */
+    private $pattern;
+
+    /** Regex pattern used for parsing the conversion pattern. */
+    private $regex;
+
+    /**
+     * First converter in the chain.
+     * @var LoggerPatternConverter
+     */
+    private $head;
+
+    /** Last converter in the chain. */
+    private $tail;
+
+    public function __construct($pattern, $converterMap) {
+        $this->pattern = $pattern;
+        $this->converterMap = $converterMap;
+
+        // Construct the regex pattern
+        $this->regex =
+            '/' .                       // Starting regex pattern delimiter
+            self::ESCAPE_CHAR .         // Character which marks the start of the conversion pattern
+            '(?P<modifiers>[0-9.-]*)' . // Format modifiers (optional)
+            '(?P<word>[a-zA-Z]+)' .     // The conversion word
+            '(?P<option>{[^}]*})?' .    // Conversion option in braces (optional)
+            '/';                        // Ending regex pattern delimiter
+    }
+
+    /**
+     * Parses the conversion pattern string, converts it to a chain of pattern
+     * converters and returns the first converter in the chain.
+     *
+     * @return LoggerPatternConverter
+     */
+    public function parse() {
+
+        // Skip parsing if the pattern is empty
+        if (empty($this->pattern)) {
+            $this->addLiteral('');
+            return $this->head;
+        }
+
+        // Find all conversion words in the conversion pattern
+        $count = preg_match_all($this->regex, $this->pattern, $matches, PREG_OFFSET_CAPTURE);
+        if ($count === false) {
+            $error = error_get_last();
+            throw new LoggerException("Failed parsing layotut pattern: {$error['message']}");
+        }
+
+        $prevEnd = 0;
+
+        foreach ($matches[0] as $key => $item) {
+
+            // Locate where the conversion command starts and ends
+            $length = strlen($item[0]);
+            $start = $item[1];
+            $end = $item[1] + $length;
+
+            // Find any literal expressions between matched commands
+            if ($start > $prevEnd) {
+                $literal = substr($this->pattern, $prevEnd, $start - $prevEnd);
+                $this->addLiteral($literal);
+            }
+
+            // Extract the data from the matched command
+            $word = !empty($matches['word'][$key]) ? $matches['word'][$key][0] : null;
+            $modifiers = !empty($matches['modifiers'][$key]) ? $matches['modifiers'][$key][0] : null;
+            $option = !empty($matches['option'][$key]) ? $matches['option'][$key][0] : null;
+
+            // Create a converter and add it to the chain
+            $this->addConverter($word, $modifiers, $option);
+
+            $prevEnd = $end;
+        }
+
+        // Add any trailing literals
+        if ($end < strlen($this->pattern)) {
+            $literal = substr($this->pattern, $end);
+            $this->addLiteral($literal);
+        }
+
+        return $this->head;
+    }
+
+    /**
+     * Adds a literal converter to the converter chain.
+     * @param string $string The string for the literal converter.
+     */
+    private function addLiteral($string) {
+        $converter = new LoggerPatternConverterLiteral($string);
+        $this->addToChain($converter);
+    }
+
+    /**
+     * Adds a non-literal converter to the converter chain.
+     *
+     * @param string $word The conversion word, used to determine which
+     *  converter will be used.
+     * @param string $modifiers Formatting modifiers.
+     * @param string $option Option to pass to the converter.
+     */
+    private function addConverter($word, $modifiers, $option) {
+        $formattingInfo = $this->parseModifiers($modifiers);
+        $option = trim($option, "{} ");
+
+        if (isset($this->converterMap[$word])) {
+            $converter = $this->getConverter($word, $formattingInfo, $option);
+            $this->addToChain($converter);
+        } else {
+            trigger_error("log4php: Invalid keyword '%$word' in converison pattern. Ignoring keyword.", E_USER_WARNING);
+        }
+    }
+
+    /**
+     * Determines which converter to use based on the conversion word. Creates
+     * an instance of the converter using the provided formatting info and
+     * option and returns it.
+     *
+     * @param string $word The conversion word.
+     * @param LoggerFormattingInfo $info Formatting info.
+     * @param string $option Converter option.
+     *
+     * @throws LoggerException
+     *
+     * @return LoggerPatternConverter
+     */
+    private function getConverter($word, $info, $option) {
+        if (!isset($this->converterMap[$word])) {
+            throw new LoggerException("Invalid keyword '%$word' in converison pattern. Ignoring keyword.");
+        }
+
+        $converterClass = $this->converterMap[$word];
+        if (!class_exists($converterClass)) {
+            throw new LoggerException("Class '$converterClass' does not exist.");
+        }
+
+        $converter = new $converterClass($info, $option);
+        if (!($converter instanceof LoggerPatternConverter)) {
+            throw new LoggerException("Class '$converterClass' is not an instance of LoggerPatternConverter.");
+        }
+
+        return $converter;
+    }
+
+    /** Adds a converter to the chain and updates $head and $tail pointers. */
+    private function addToChain(LoggerPatternConverter $converter) {
+        if (!isset($this->head)) {
+            $this->head = $converter;
+            $this->tail = $this->head;
+        } else {
+            $this->tail->next = $converter;
+            $this->tail = $this->tail->next;
+        }
+    }
+
+    /**
+     * Parses the formatting modifiers and produces the corresponding
+     * LoggerFormattingInfo object.
+     *
+     * @param string $modifier
+     * @return LoggerFormattingInfo
+     * @throws LoggerException
+     */
+    private function parseModifiers($modifiers) {
+        $info = new LoggerFormattingInfo();
+
+        // If no modifiers are given, return default values
+        if (empty($modifiers)) {
+            return $info;
+        }
+
+        // Validate
+        $pattern = '/^(-?[0-9]+)?\.?-?[0-9]+$/';
+        if (!preg_match($pattern, $modifiers)) {
+            trigger_error("log4php: Invalid modifier in conversion pattern: [$modifiers]. Ignoring modifier.", E_USER_WARNING);
+            return $info;
+        }
+
+        $parts = explode('.', $modifiers);
+
+        if (!empty($parts[0])) {
+            $minPart = (integer)$parts[0];
+            $info->min = abs($minPart);
+            $info->padLeft = ($minPart > 0);
+        }
+
+        if (!empty($parts[1])) {
+            $maxPart = (integer)$parts[1];
+            $info->max = abs($maxPart);
+            $info->trimLeft = ($maxPart < 0);
+        }
+
+        return $info;
+    }
+}