Improved documentation and coding style.

27 files changed, 127 insertions, 118 deletions

diff --git a/src/Context.php b/src/Context.php
index 2b43e56..4c73af2 100644
--- a/src/Context.php
+++ b/src/Context.php
@@ -372,12 +372,14 @@ abstract class Context
         $len = strlen($str);
         if ($str[0] === '#') {
             return Token::FLAG_COMMENT_BASH;
-        } elseif (($len > 1) && ((($str[0] === '/') && ($str[1] === '*')) ||
-                                  (($str[0] === '*') && ($str[1] === '/')))) {
+        } elseif (($len > 1) && ((($str[0] === '/') && ($str[1] === '*'))
+            || (($str[0] === '*') && ($str[1] === '/')))
+        ) {
             return Token::FLAG_COMMENT_C;
-        } elseif (($len > 2) && ($str[0] === '-') &&
-            ($str[1] === '-') && ($str[2] !== "\n") &&
-            (static::isWhitespace($str[2]))) {
+        } elseif (($len > 2) && ($str[0] === '-')
+            && ($str[1] === '-') && ($str[2] !== "\n")
+            && (static::isWhitespace($str[2]))
+        ) {
             return Token::FLAG_COMMENT_SQL;
         }
         return null;
@@ -413,8 +415,8 @@ abstract class Context
      */
     public static function isNumber($ch)
     {
-        return (($ch >= '0') && ($ch <= '9')) || ($ch === '.') ||
-            ($ch === '-') || ($ch === '+') || ($ch === 'e') || ($ch === 'E');
+        return (($ch >= '0') && ($ch <= '9')) || ($ch === '.')
+            || ($ch === '-') || ($ch === '+') || ($ch === 'e') || ($ch === 'E');
     }
 
     // -------------------------------------------------------------------------
diff --git a/src/Exceptions/LexerException.php b/src/Exceptions/LexerException.php
index f346d83..306c8b9 100644
--- a/src/Exceptions/LexerException.php
+++ b/src/Exceptions/LexerException.php
@@ -27,14 +27,14 @@ class LexerException extends \Exception
     /**
      * Constructor.
      *
-     * @param string $message
-     * @param string $ch
-     * @param int $positiion
-     * @param int $code
+     * @param string $msg The message of this exception.
+     * @param string $ch The character that produced this exception.
+     * @param int $pos The position of the character.
+     * @param int $code The code of this error.
      */
-    public function __construct($message = '', $ch = '', $pos = 0, $code = 0)
+    public function __construct($msg = '', $ch = '', $pos = 0, $code = 0)
     {
-        parent::__construct($message, $code);
+        parent::__construct($msg, $code);
         $this->ch = $ch;
         $this->pos = $pos;
     }
diff --git a/src/Exceptions/ParserException.php b/src/Exceptions/ParserException.php
index e23d03d..7332674 100644
--- a/src/Exceptions/ParserException.php
+++ b/src/Exceptions/ParserException.php
@@ -20,13 +20,13 @@ class ParserException extends \Exception
     /**
      * Constructor.
      *
-     * @param string $message
-     * @param Token $token
-     * @param int $code
+     * @param string $msg The message of this exception.
+     * @param Token $token The token that produced this exception.
+     * @param int $code The code of this error.
      */
-    public function __construct($message = '', Token $token = null, $code = 0)
+    public function __construct($msg = '', Token $token = null, $code = 0)
     {
-        parent::__construct($message, $code);
+        parent::__construct($msg, $code);
         $this->token = $token;
     }
 }
diff --git a/src/Fragment.php b/src/Fragment.php
index e9a4620..86f9d36 100644
--- a/src/Fragment.php
+++ b/src/Fragment.php
@@ -20,9 +20,9 @@ abstract class Fragment
     /**
      * Parses the tokens given by the lexer in the context of the given parser.
      *
-     * @param Parser $parser
-     * @param TokensList $list
-     * @param array $options
+     * @param Parser $parser The parser that serves as context.
+     * @param TokensList $list The list of tokens that are being parsed.
+     * @param array $options Parameters for parsing.
      *
      * @return array
      */
diff --git a/src/Fragments/ArrayFragment.php b/src/Fragments/ArrayFragment.php
index 9ff8649..3b796b7 100644
--- a/src/Fragments/ArrayFragment.php
+++ b/src/Fragments/ArrayFragment.php
@@ -22,9 +22,9 @@ class ArrayFragment extends Fragment
     public $array = array();
 
     /**
-     * @param Parser $parser
-     * @param TokensList $list
-     * @param array $options
+     * @param Parser $parser The parser that serves as context.
+     * @param TokensList $list The list of tokens that are being parsed.
+     * @param array $options Parameters for parsing.
      *
      * @return ArrayFragment
      */
diff --git a/src/Fragments/CallKeyword.php b/src/Fragments/CallKeyword.php
index 00b7838..58ee89b 100644
--- a/src/Fragments/CallKeyword.php
+++ b/src/Fragments/CallKeyword.php
@@ -29,9 +29,9 @@ class CallKeyword extends Fragment
     public $parameters = array();
 
     /**
-     * @param Parser $parser
-     * @param TokensList $list
-     * @param array $options
+     * @param Parser $parser The parser that serves as context.
+     * @param TokensList $list The list of tokens that are being parsed.
+     * @param array $options Parameters for parsing.
      *
      * @return CallKeyword
      */
diff --git a/src/Fragments/CreateDefFragment.php b/src/Fragments/CreateDefFragment.php
index 708ce11..fefb43d 100644
--- a/src/Fragments/CreateDefFragment.php
+++ b/src/Fragments/CreateDefFragment.php
@@ -70,9 +70,9 @@ class CreateDefFragment extends Fragment
     public $name;
 
     /**
-     * @param Parser $parser
-     * @param TokensList $list
-     * @param array $options
+     * @param Parser $parser The parser that serves as context.
+     * @param TokensList $list The list of tokens that are being parsed.
+     * @param array $options Parameters for parsing.
      *
      * @return CreateDefFragment
      */
diff --git a/src/Fragments/DataTypeFragment.php b/src/Fragments/DataTypeFragment.php
index c0a4f61..ad98d0a 100644
--- a/src/Fragments/DataTypeFragment.php
+++ b/src/Fragments/DataTypeFragment.php
@@ -18,10 +18,10 @@ class DataTypeFragment extends Fragment
     public static $OPTIONS = array(
         'BINARY'                        => 1,
         'CHARACTER SET'                 => array(2, 'var'),
-        'CHARSET'                       => array(3, 'var'),
-        'COLLATE'                       => 4,
-        'UNSIGNED'                      => 5,
-        'ZEROFILL'                      => 6,
+        'CHARSET'                       => array(2, 'var'),
+        'COLLATE'                       => 3,
+        'UNSIGNED'                      => 4,
+        'ZEROFILL'                      => 5,
     );
 
     /**
@@ -46,9 +46,9 @@ class DataTypeFragment extends Fragment
     public $options = array();
 
     /**
-     * @param Parser $parser
-     * @param TokensList $list
-     * @param array $options
+     * @param Parser $parser The parser that serves as context.
+     * @param TokensList $list The list of tokens that are being parsed.
+     * @param array $options Parameters for parsing.
      *
      * @return DataTypeFragment[]
      */
diff --git a/src/Fragments/FieldDefFragment.php b/src/Fragments/FieldDefFragment.php
index fe94184..6cbe58e 100644
--- a/src/Fragments/FieldDefFragment.php
+++ b/src/Fragments/FieldDefFragment.php
@@ -52,9 +52,9 @@ class FieldDefFragment extends Fragment
     /**
      * The array of indexes.
      *
-     * @var array
+     * @var ArrayFragment
      */
-    public $indexes = array();
+    public $indexes;
 
     /**
      * The options of the new field fragment.
@@ -64,9 +64,9 @@ class FieldDefFragment extends Fragment
     public $options;
 
     /**
-     * @param Parser $parser
-     * @param TokensList $list
-     * @param array $options
+     * @param Parser $parser The parser that serves as context.
+     * @param TokensList $list The list of tokens that are being parsed.
+     * @param array $options Parameters for parsing.
      *
      * @return FieldDefFragment[]
      */
diff --git a/src/Fragments/FieldFragment.php b/src/Fragments/FieldFragment.php
index 71e1066..0402b3f 100644
--- a/src/Fragments/FieldFragment.php
+++ b/src/Fragments/FieldFragment.php
@@ -50,9 +50,9 @@ class FieldFragment extends Fragment
     public $alias;
 
     /**
-     * @param Parser $parser
-     * @param TokensList $list
-     * @param array $options
+     * @param Parser $parser The parser that serves as context.
+     * @param TokensList $list The list of tokens that are being parsed.
+     * @param array $options Parameters for parsing.
      *
      * @return FieldFragment
      */
@@ -121,9 +121,9 @@ class FieldFragment extends Fragment
                 }
             }
 
-            if (($token->type === Token::TYPE_NUMBER) || ($token->type === Token::TYPE_BOOL) ||
-                (($token->type === Token::TYPE_SYMBOL) && ($token->flags & Token::FLAG_SYMBOL_VARIABLE)) ||
-                (($token->type === Token::TYPE_OPERATOR)) && ($token->value !== '.')) {
+            if (($token->type === Token::TYPE_NUMBER) || ($token->type === Token::TYPE_BOOL)
+                || (($token->type === Token::TYPE_SYMBOL) && ($token->flags & Token::FLAG_SYMBOL_VARIABLE))
+                || (($token->type === Token::TYPE_OPERATOR)) && ($token->value !== '.')) {
                 // Numbers, booleans and operators are usually part of expressions.
                 $isExpr = true;
             }
@@ -147,8 +147,9 @@ class FieldFragment extends Fragment
                     }
                 } else {
                     if ($brackets === 0) {
-                        if (($token->type === Token::TYPE_NONE) || ($token->type === Token::TYPE_STRING) ||
-                            (($token->type === Token::TYPE_SYMBOL) && ($token->flags & Token::FLAG_SYMBOL_BACKTICK))) {
+                        if (($token->type === Token::TYPE_NONE) || ($token->type === Token::TYPE_STRING)
+                            || (($token->type === Token::TYPE_SYMBOL) && ($token->flags & Token::FLAG_SYMBOL_BACKTICK))
+                        ) {
                             $ret->alias = $token->value;
                         }
                     }
diff --git a/src/Fragments/FromKeyword.php b/src/Fragments/FromKeyword.php
index fd11eea..dd1f263 100644
--- a/src/Fragments/FromKeyword.php
+++ b/src/Fragments/FromKeyword.php
@@ -15,9 +15,9 @@ class FromKeyword extends Fragment
 {
 
     /**
-     * @param Parser $parser
-     * @param TokensList $list
-     * @param array $options
+     * @param Parser $parser The parser that serves as context.
+     * @param TokensList $list The list of tokens that are being parsed.
+     * @param array $options Parameters for parsing.
      *
      * @return FieldFragment[]
      */
diff --git a/src/Fragments/IntoKeyword.php b/src/Fragments/IntoKeyword.php
index 9f6a116..888a55e 100644
--- a/src/Fragments/IntoKeyword.php
+++ b/src/Fragments/IntoKeyword.php
@@ -29,9 +29,9 @@ class IntoKeyword extends Fragment
     public $fields;
 
     /**
-     * @param Parser $parser
-     * @param TokensList $list
-     * @param array $options
+     * @param Parser $parser The parser that serves as context.
+     * @param TokensList $list The list of tokens that are being parsed.
+     * @param array $options Parameters for parsing.
      *
      * @return IntoKeyword
      */
diff --git a/src/Fragments/JoinKeyword.php b/src/Fragments/JoinKeyword.php
index 62f9ecd..411d227 100644
--- a/src/Fragments/JoinKeyword.php
+++ b/src/Fragments/JoinKeyword.php
@@ -29,9 +29,9 @@ class JoinKeyword extends Fragment
     public $on;
 
     /**
-     * @param Parser $parser
-     * @param TokensList $list
-     * @param array $options
+     * @param Parser $parser The parser that serves as context.
+     * @param TokensList $list The list of tokens that are being parsed.
+     * @param array $options Parameters for parsing.
      *
      * @return JoinKeyword
      */
diff --git a/src/Fragments/LimitKeyword.php b/src/Fragments/LimitKeyword.php
index 08fb3a4..4b59137 100644
--- a/src/Fragments/LimitKeyword.php
+++ b/src/Fragments/LimitKeyword.php
@@ -29,9 +29,9 @@ class LimitKeyword extends Fragment
     public $row_count;
 
     /**
-     * @param Parser $parser
-     * @param TokensList $list
-     * @param array $options
+     * @param Parser $parser The parser that serves as context.
+     * @param TokensList $list The list of tokens that are being parsed.
+     * @param array $options Parameters for parsing.
      *
      * @return LimitKeyword
      */
diff --git a/src/Fragments/OptionsFragment.php b/src/Fragments/OptionsFragment.php
index 22661eb..1a39c6c 100644
--- a/src/Fragments/OptionsFragment.php
+++ b/src/Fragments/OptionsFragment.php
@@ -22,9 +22,9 @@ class OptionsFragment extends Fragment
     public $options = array();
 
     /**
-     * @param Parser $parser
-     * @param TokensList $list
-     * @param array $options
+     * @param Parser $parser The parser that serves as context.
+     * @param TokensList $list The list of tokens that are being parsed.
+     * @param array $options Parameters for parsing.
      *
      * @return OptionsFragment
      */
diff --git a/src/Fragments/OrderKeyword.php b/src/Fragments/OrderKeyword.php
index 5ddc8ef..1bc6b8f 100644
--- a/src/Fragments/OrderKeyword.php
+++ b/src/Fragments/OrderKeyword.php
@@ -29,9 +29,9 @@ class OrderKeyword extends Fragment
     public $type = 'ASC';
 
     /**
-     * @param Parser $parser
-     * @param TokensList $list
-     * @param array $options
+     * @param Parser $parser The parser that serves as context.
+     * @param TokensList $list The list of tokens that are being parsed.
+     * @param array $options Parameters for parsing.
      *
      * @return OrderKeyword[]
      */
diff --git a/src/Fragments/ParamDefFragment.php b/src/Fragments/ParamDefFragment.php
index b7d414d..c2582ef 100644
--- a/src/Fragments/ParamDefFragment.php
+++ b/src/Fragments/ParamDefFragment.php
@@ -37,9 +37,9 @@ class ParamDefFragment extends Fragment
     public $type;
 
     /**
-     * @param Parser $parser
-     * @param TokensList $list
-     * @param array $options
+     * @param Parser $parser The parser that serves as context.
+     * @param TokensList $list The list of tokens that are being parsed.
+     * @param array $options Parameters for parsing.
      *
      * @return ParamDefFragment[]
      */
diff --git a/src/Fragments/RenameKeyword.php b/src/Fragments/RenameKeyword.php
index 7841b2a..dd8b2f9 100644
--- a/src/Fragments/RenameKeyword.php
+++ b/src/Fragments/RenameKeyword.php
@@ -29,9 +29,9 @@ class RenameKeyword extends Fragment
     public $new;
 
     /**
-     * @param Parser $parser
-     * @param TokensList $list
-     * @param array $options
+     * @param Parser $parser The parser that serves as context.
+     * @param TokensList $list The list of tokens that are being parsed.
+     * @param array $options Parameters for parsing.
      *
      * @return RenameKeyword
      */
diff --git a/src/Fragments/SelectKeyword.php b/src/Fragments/SelectKeyword.php
index dc8db95..9b28812 100644
--- a/src/Fragments/SelectKeyword.php
+++ b/src/Fragments/SelectKeyword.php
@@ -15,9 +15,9 @@ class SelectKeyword extends Fragment
 {
 
     /**
-     * @param Parser $parser
-     * @param TokensList $list
-     * @param array $options
+     * @param Parser $parser The parser that serves as context.
+     * @param TokensList $list The list of tokens that are being parsed.
+     * @param array $options Parameters for parsing.
      *
      * @return FieldFragment[]
      */
diff --git a/src/Fragments/SetKeyword.php b/src/Fragments/SetKeyword.php
index 1e70f27..170b076 100644
--- a/src/Fragments/SetKeyword.php
+++ b/src/Fragments/SetKeyword.php
@@ -29,9 +29,9 @@ class SetKeyword extends Fragment
     public $value;
 
     /**
-     * @param Parser $parser
-     * @param TokensList $list
-     * @param array $options
+     * @param Parser $parser The parser that serves as context.
+     * @param TokensList $list The list of tokens that are being parsed.
+     * @param array $options Parameters for parsing.
      *
      * @return SetKeyword[]
      */
diff --git a/src/Fragments/ValuesKeyword.php b/src/Fragments/ValuesKeyword.php
index c6bd551..8fce245 100644
--- a/src/Fragments/ValuesKeyword.php
+++ b/src/Fragments/ValuesKeyword.php
@@ -22,9 +22,9 @@ class ValuesKeyword extends Fragment
     public $values;
 
     /**
-     * @param Parser $parser
-     * @param TokensList $list
-     * @param array $options
+     * @param Parser $parser The parser that serves as context.
+     * @param TokensList $list The list of tokens that are being parsed.
+     * @param array $options Parameters for parsing.
      *
      * @return ValuesKeyword
      */
diff --git a/src/Fragments/WhereKeyword.php b/src/Fragments/WhereKeyword.php
index 786efbf..9c30513 100644
--- a/src/Fragments/WhereKeyword.php
+++ b/src/Fragments/WhereKeyword.php
@@ -36,9 +36,9 @@ class WhereKeyword extends Fragment
     public $condition;
 
     /**
-     * @param Parser $parser
-     * @param TokensList $list
-     * @param array $options
+     * @param Parser $parser The parser that serves as context.
+     * @param TokensList $list The list of tokens that are being parsed.
+     * @param array $options Parameters for parsing.
      *
      * @return WhereKeyword[]
      */
diff --git a/src/Lexer.php b/src/Lexer.php
index 2b980ab..be92301 100644
--- a/src/Lexer.php
+++ b/src/Lexer.php
@@ -106,8 +106,8 @@ class Lexer
     /**
      * Constructor.
      *
-     * @param string|UtfString $str
-     * @param bool $strict
+     * @param string|UtfString $str The query to be lexed.
+     * @param bool $strict Whether strict mode should be enabled or not.
      */
     public function __construct($str, $strict = false)
     {
@@ -120,8 +120,6 @@ class Lexer
 
     /**
      * Parses the string and extracts lexems.
-     *
-     * @param string|UtfString $str
      */
     public function lex()
     {
@@ -153,11 +151,15 @@ class Lexer
                 if ($this->delimiter !== $this->str[$this->last]) {
                     $this->error('Unexpected character.', $this->str[$this->last], $this->last);
                 }
-            } elseif (($token->type === Token::TYPE_SYMBOL) && ($token->flags & Token::FLAG_SYMBOL_VARIABLE) &&
-                    ($lastToken !== null)) {
+            } elseif (($token->type === Token::TYPE_SYMBOL)
+                && ($token->flags & Token::FLAG_SYMBOL_VARIABLE)
+                && ($lastToken !== null)
+            ) {
                 // Handles ```... FROM 'user'@'%' ...```.
-                if ((($lastToken->type === Token::TYPE_SYMBOL) && ($lastToken->flags & Token::FLAG_SYMBOL_BACKTICK)) ||
-                       ($lastToken->type === Token::TYPE_STRING)) {
+                if ((($lastToken->type === Token::TYPE_SYMBOL)
+                    && ($lastToken->flags & Token::FLAG_SYMBOL_BACKTICK))
+                    || ($lastToken->type === Token::TYPE_STRING)
+                ) {
                     $lastToken->token .= $token->token;
                     $lastToken->type = Token::TYPE_SYMBOL;
                     $lastToken->flags = Token::FLAG_SYMBOL_USER;
@@ -199,9 +201,10 @@ class Lexer
     /**
      * Creates a new error log.
      *
-     * @param string $msg
-     * @param string $str
-     * @param int $code
+     * @param string $msg The error message.
+     * @param string $ch The character that produced the error.
+     * @param int $pos The position of the character.
+     * @param int $code The code of the error.
      */
     public function error($msg = '', $str = '', $pos = 0, $code = 0)
     {
@@ -427,8 +430,9 @@ class Lexer
                 } elseif ($this->str[$this->last] === '-') {
                     $flags |= Token::FLAG_NUMBER_NEGATIVE;
                     // Do nothing.
-                } elseif (($this->str[$this->last] === '0') && ($this->last + 1 < $this->len) &&
-                        (($this->str[$this->last + 1] === 'x') || ($this->str[$this->last + 1] === 'X'))) {
+                } elseif (($this->str[$this->last] === '0') && ($this->last + 1 < $this->len)
+                    && (($this->str[$this->last + 1] === 'x') || ($this->str[$this->last + 1] === 'X'))
+                ) {
                     $token .= $this->str[$this->last++];
                     $state = 2;
                 } elseif (($this->str[$this->last] >= '0') && ($this->str[$this->last] <= '9')) {
@@ -440,9 +444,10 @@ class Lexer
                 }
             } elseif ($state === 2) {
                 $flags |= Token::FLAG_NUMBER_HEX;
-                if ((($this->str[$this->last] >= '0') && ($this->str[$this->last] <= '9')) ||
-                    (($this->str[$this->last] >= 'A') && ($this->str[$this->last] <= 'F')) ||
-                    (($this->str[$this->last] >= 'a') && ($this->str[$this->last] <= 'f'))) {
+                if ((($this->str[$this->last] >= '0') && ($this->str[$this->last] <= '9'))
+                    || (($this->str[$this->last] >= 'A') && ($this->str[$this->last] <= 'F'))
+                    || (($this->str[$this->last] >= 'a') && ($this->str[$this->last] <= 'f'))
+                ) {
                     // Do nothing.
                 } else {
                     break;
@@ -494,7 +499,7 @@ class Lexer
     /**
      * Parses a string.
      *
-     * @param string $quote Additional start symbol.
+     * @param string $quote Additional starting symbol.
      *
      * @return Token
      */
@@ -507,9 +512,10 @@ class Lexer
         $quote = $token;
 
         while (++$this->last < $this->len) {
-            if (($this->last + 1 < $this->len) &&
-                ((($this->str[$this->last] === $quote) && ($this->str[$this->last + 1] === $quote)) ||
-                (($this->str[$this->last] === '\\') && ($quote !== '`')))) {
+            if (($this->last + 1 < $this->len)
+                && ((($this->str[$this->last] === $quote) && ($this->str[$this->last + 1] === $quote))
+                || (($this->str[$this->last] === '\\') && ($quote !== '`')))
+            ) {
                 $token .= $this->str[$this->last] . $this->str[++$this->last];
             } else {
                 if ($this->str[$this->last] === $quote) {
diff --git a/src/Parser.php b/src/Parser.php
index 167e912..059faa5 100644
--- a/src/Parser.php
+++ b/src/Parser.php
@@ -119,8 +119,8 @@ class Parser
     /**
      * Constructor.
      *
-     * @param mixed $list
-     * @param bool $strict
+     * @param mixed $list The list of tokens to be parsed.
+     * @param bool $strict Whether strict mode should be enabled or not.
      */
     public function __construct($list = null, $strict = false)
     {
@@ -181,9 +181,9 @@ class Parser
     /**
      * Creates a new error log.
      *
-     * @param string $str
-     * @param Token $token
-     * @param int $code
+     * @param string $msg The error message.
+     * @param Token $token The token that produced the error.
+     * @param int $code The code of the error.
      */
     public function error($str = '', Token $token = null, $code = 0)
     {
diff --git a/src/UtfString.php b/src/UtfString.php
index 8815e58..0f68cfe 100644
--- a/src/UtfString.php
+++ b/src/UtfString.php
@@ -154,7 +154,7 @@ class UtfString implements \ArrayAccess
      *
      * @return int
      */
-    private static function getCharLength($byte)
+    public static function getCharLength($byte)
     {
         $byte = ord($byte);
         if ($byte < 128) {
diff --git a/src/Utils/Misc.php b/src/Utils/Misc.php
index dc8b438..473bf9b 100644
--- a/src/Utils/Misc.php
+++ b/src/Utils/Misc.php
@@ -2,7 +2,7 @@
 
 namespace SqlParser\Utils;
 
-use SqlParser\Statement;
+use SqlParser\Statements\SelectStatement;
 
 class Misc
 {
@@ -10,12 +10,12 @@ class Misc
     /**
      * Gets a list of all aliases and their original names.
      *
-     * @param Statement $tree
+     * @param SelectStatement $tree The tree that was generated after parsing.
      * @param string $db
      *
      * @return array
      */
-    public static function getAliases($tree, $db)
+    public static function getAliases(SelectStatement $tree, $db)
     {
         $retval = array();
 
diff --git a/src/Utils/Routine.php b/src/Utils/Routine.php
index 126ed53..36511ca 100644
--- a/src/Utils/Routine.php
+++ b/src/Utils/Routine.php
@@ -4,9 +4,9 @@ namespace SqlParser\Utils;
 
 use SqlParser\Lexer;
 use SqlParser\Parser;
-use SqlParser\Statement;
 use SqlParser\Fragments\DataTypeFragment;
 use SqlParser\Fragments\ParamDefFragment;
+use SqlParser\Statements\CreateStatement;
 
 class Routine
 {
@@ -80,11 +80,11 @@ class Routine
     /**
      * Gets the parameters of a routine from the parse tree.
      *
-     * @param Statement $tree
+     * @param CreateStatement $tree The tree that was generated after parsing.
      *
      * @return array
      */
-    public static function getParameters(Statement $tree)
+    public static function getParameters(CreateStatement $tree)
     {
         $retval = array(
             'num' => 0,