diff options
Diffstat (limited to 'lib/SqlFormatter.php')
| -rw-r--r-- | lib/SqlFormatter.php | 63 |
1 files changed, 56 insertions, 7 deletions
diff --git a/lib/SqlFormatter.php b/lib/SqlFormatter.php index bc59498..e66b23b 100644 --- a/lib/SqlFormatter.php +++ b/lib/SqlFormatter.php @@ -8,7 +8,7 @@ * @copyright 2012 Jeremy Dorn * @license http://www.opensource.org/licenses/lgpl-license.php LGPL * @link http://github.com/jdorn/sql-formatter - * @version 1.1.0 + * @version 1.2.0 */ class SqlFormatter { @@ -76,6 +76,26 @@ class SqlFormatter // This is a combination of all the boundary characters and all the whitespace characters protected static $all_boundaries; + //cache variables + //Only tokens shorter than this size will be cached. Somewhere between 10 and 20 seems to work well for most cases. + public static $max_cachekey_size = 15; + protected static $token_cache = array(); + protected static $cache_hits = 0; + protected static $cache_misses = 0; + + /** + * Get stats about the token cache + * @return Array An array containing the keys 'hits', 'misses', 'entries', and 'size' in bytes + */ + public static function getCacheStats() { + return array( + 'hits'=>self::$cache_hits, + 'misses'=>self::$cache_misses, + 'entries'=>count(self::$token_cache), + 'size'=>strlen(serialize(self::$token_cache)) + ); + } + /** * Return the next token and token type in a SQL string. * Quoted strings, comments, reserved words, whitespace, and punctuation are all their own tokens. @@ -284,21 +304,50 @@ class SqlFormatter $old_string_len = strlen($string) + 1; $token = null; + + $current_length = strlen($string); // Keep processing the string until it is empty - while (strlen($string)) { + while ($current_length) { // If the string stopped shrinking, there was a problem - if ($old_string_len <= strlen($string)) { + if ($old_string_len <= $current_length) { throw new Exception("SQL Parse Error - Unable to tokenize string at character ".($original_length - $old_string_len)); } - $old_string_len = strlen($string); + $old_string_len = $current_length; - // Get the next token and the token type - $token = self::getNextToken($string, $token); + // Determine if we can use caching + if($current_length >= self::$max_cachekey_size) { + $cacheKey = substr($string,0,self::$max_cachekey_size); + } + else { + $cacheKey = false; + } + + // See if the token is already cached + if($cacheKey && isset(self::$token_cache[$cacheKey])) { + //retrieve from cache + $token = self::$token_cache[$cacheKey]; + $token_length = strlen($token['token']); + self::$cache_hits++; + } + else { + // Get the next token and the token type + $token = self::getNextToken($string, $token); + $token_length = strlen($token['token']); + self::$cache_misses++; + + // If the token is shorter than the max length, store it in cache + if($cacheKey && $token_length < self::$max_cachekey_size) { + self::$token_cache[$cacheKey] = $token; + } + } + $tokens[] = $token; //advance the string - $string = substr($string, strlen($token['token'])); + $string = substr($string, $token_length); + + $current_length -= $token_length; } return $tokens; |