diff --git a/Formatter/SwaggerFormatter.php b/Formatter/SwaggerFormatter.php
index 33caba7..2de44ed 100644
--- a/Formatter/SwaggerFormatter.php
+++ b/Formatter/SwaggerFormatter.php
@@ -442,7 +442,7 @@ class SwaggerFormatter implements FormatterInterface
                     case DataTypes::ENUM:
                         $type = 'string';
                         if (isset($prop['format'])) {
-                            $enum = array_keys(json_decode($prop['format'], true));
+                            $enum = explode('|', rtrim(ltrim($prop['format'], '['), ']'));
                         }
                         break;
 
diff --git a/Parser/FormTypeParser.php b/Parser/FormTypeParser.php
index 2ea8bc7..98dbb83 100644
--- a/Parser/FormTypeParser.php
+++ b/Parser/FormTypeParser.php
@@ -367,7 +367,11 @@ class FormTypeParser implements ParserInterface
                     }
 
                     if (($choices = $config->getOption('choices')) && is_array($choices) && count($choices)) {
-                        $parameters[$name]['format'] = json_encode($choices);
+                        $choices = $config->getOption('choices_as_values') ?
+                            array_values($choices) :
+                            array_keys($choices);
+                        sort($choices);
+                        $parameters[$name]['format'] = '[' . join('|', $choices) . ']';
                     } elseif ($choiceList = $config->getOption('choice_list')) {
                         $choiceListType = $config->getType();
                         $choiceListName = method_exists($choiceListType, 'getBlockPrefix') ?
diff --git a/Parser/ValidationParser.php b/Parser/ValidationParser.php
index 3dcc63a..af13a1b 100644
--- a/Parser/ValidationParser.php
+++ b/Parser/ValidationParser.php
@@ -137,7 +137,7 @@ class ValidationParser implements ParserInterface, PostParserInterface
             }
 
             if (isset($vparams['format'])) {
-                $vparams['format'] = join(', ', $vparams['format']);
+                $vparams['format'] = join(', ', array_unique($vparams['format']));
             }
 
             foreach (array('dataType', 'readonly', 'required', 'subType') as $reqprop) {
@@ -283,6 +283,7 @@ class ValidationParser implements ParserInterface, PostParserInterface
                 break;
             case 'Choice':
                 $choices = $this->getChoices($constraint, $className);
+                sort($choices);
                 $format = '[' . join('|', $choices) . ']';
                 if ($constraint->multiple) {
                     $vparams['actualType'] = DataTypes::COLLECTION;
diff --git a/Tests/Formatter/SwaggerFormatterTest.php b/Tests/Formatter/SwaggerFormatterTest.php
index b321f41..339bea8 100644
--- a/Tests/Formatter/SwaggerFormatterTest.php
+++ b/Tests/Formatter/SwaggerFormatterTest.php
@@ -289,9 +289,9 @@ class SwaggerFormatterTest extends WebTestCase
                                                             'type'      => 'string',
                                                             'enum'      =>
                                                                 array(
-                                                                    0 => 'x',
-                                                                    1 => 'y',
-                                                                    2 => 'z',
+                                                                    0 => 'X',
+                                                                    1 => 'Y',
+                                                                    2 => 'Z',
                                                                 ),
                                                         ),
                                                     4 =>
diff --git a/Tests/Formatter/testFormat-result-no-dunglas.php b/Tests/Formatter/testFormat-result-no-dunglas.php
index ff3d08b..a2a9a10 100644
--- a/Tests/Formatter/testFormat-result-no-dunglas.php
+++ b/Tests/Formatter/testFormat-result-no-dunglas.php
@@ -466,7 +466,7 @@ With multiple lines.',
           'required' => true,
           'description' => NULL,
           'readonly' => false,
-          'format' => '{"x":"X","y":"Y","z":"Z"}',
+          'format' => '[X|Y|Z]',
         ),
         'd' =>
         array (
diff --git a/Tests/Formatter/testFormat-result.php b/Tests/Formatter/testFormat-result.php
index f72063f..92f44e1 100644
--- a/Tests/Formatter/testFormat-result.php
+++ b/Tests/Formatter/testFormat-result.php
@@ -464,7 +464,7 @@ With multiple lines.',
                                     'required' => true,
                                     'description' => NULL,
                                     'readonly' => false,
-                                    'format' => '{"x":"X","y":"Y","z":"Z"}',
+                                    'format' => '[X|Y|Z]',
                                 ),
                             'd' =>
                                 array (
diff --git a/Tests/Parser/FormTypeParserTest.php b/Tests/Parser/FormTypeParserTest.php
index 5222859..37d87ae 100644
--- a/Tests/Parser/FormTypeParserTest.php
+++ b/Tests/Parser/FormTypeParserTest.php
@@ -121,7 +121,7 @@ class FormTypeParserTest extends \PHPUnit_Framework_TestCase
                 'description' => '',
                 'readonly' => false,
             ),
-            LegacyFormHelper::isLegacy() ? array() : array('format' => '{"foo":"bar","bazgroup":{"baz":"Buzz"}}',)
+            LegacyFormHelper::isLegacy() ? array() : array('format' => '[bar|Array]',)
         );
 
         return array(
@@ -446,7 +446,7 @@ class FormTypeParserTest extends \PHPUnit_Framework_TestCase
                         'required' => true,
                         'description' => '',
                         'readonly' => false,
-                        'format' => json_encode(array('m' => 'Male', 'f' => 'Female')),
+                        'format' => '[Female|Male]',
                     ),
                     'c2' => array(
                         'dataType' => 'array of choices',
@@ -456,7 +456,7 @@ class FormTypeParserTest extends \PHPUnit_Framework_TestCase
                         'required' => true,
                         'description' => '',
                         'readonly' => false,
-                        'format' => json_encode(array('m' => 'Male', 'f' => 'Female')),
+                        'format' => '[Female|Male]',
                     ),
                     'c3' => array(
                         'dataType' => 'choice',
@@ -475,7 +475,7 @@ class FormTypeParserTest extends \PHPUnit_Framework_TestCase
                         'required' => true,
                         'description' => '',
                         'readonly' => false,
-                        'format' => '{"foo":"bar","bazgroup":{"baz":"Buzz"}}',
+                        'format' => '[bar|Array]',
                     ),
                     'e1' => $entityData
                 ),
@@ -523,7 +523,7 @@ class FormTypeParserTest extends \PHPUnit_Framework_TestCase
                                             'required' => true,
                                             'description' => '',
                                             'readonly' => false,
-                                            'format' => '{"x":"X","y":"Y","z":"Z"}',
+                                            'format' => '[X|Y|Z]',
                                         ),
                                     'd' =>
                                         array (
diff --git a/Tests/Parser/ValidationParserTest.php b/Tests/Parser/ValidationParserTest.php
index c8a6299..c21ac7f 100644
--- a/Tests/Parser/ValidationParserTest.php
+++ b/Tests/Parser/ValidationParserTest.php
@@ -155,7 +155,7 @@ class ValidationParserTest extends WebTestCase
             array(
                 'property' => 'multiplerangechoice',
                 'expected' => array(
-                    'format' => '{min: 2 max: 3 choice of [foo|bar|baz|qux]}',
+                    'format' => '{min: 2 max: 3 choice of [bar|baz|foo|qux]}',
                     'actualType' => DataTypes::COLLECTION,
                     'subType' => DataTypes::ENUM,
                     'default' => null,