[Java][okhttp-gson] fix failure to deserialize floats (#3846)

* fixed bug where nullApi.java would be generated.  Instead, generated DefaultApi.java to match the default path /{pathParam}

* fix to bug #3157

* update samples

samples/client/petstore/python/petstore_api/models/type_holder_example.py

@@ -33,6 +33,7 @@ class TypeHolderExample(object):
     openapi_types = {
         'string_item': 'str',
         'number_item': 'float',
+        'float_item': 'float',
         'integer_item': 'int',
         'bool_item': 'bool',
         'array_item': 'list[int]'
@@ -41,16 +42,18 @@ class TypeHolderExample(object):
     attribute_map = {
         'string_item': 'string_item',
         'number_item': 'number_item',
+        'float_item': 'float_item',
         'integer_item': 'integer_item',
         'bool_item': 'bool_item',
         'array_item': 'array_item'
     }
 
-    def __init__(self, string_item=None, number_item=None, integer_item=None, bool_item=None, array_item=None):  # noqa: E501
+    def __init__(self, string_item=None, number_item=None, float_item=None, integer_item=None, bool_item=None, array_item=None):  # noqa: E501
         """TypeHolderExample - a model defined in OpenAPI"""  # noqa: E501
 
         self._string_item = None
         self._number_item = None
+        self._float_item = None
         self._integer_item = None
         self._bool_item = None
         self._array_item = None
@@ -58,6 +61,7 @@ class TypeHolderExample(object):
 
         self.string_item = string_item
         self.number_item = number_item
+        self.float_item = float_item
         self.integer_item = integer_item
         self.bool_item = bool_item
         self.array_item = array_item
@@ -108,6 +112,29 @@ class TypeHolderExample(object):
 
         self._number_item = number_item
 
+    @property
+    def float_item(self):
+        """Gets the float_item of this TypeHolderExample.  # noqa: E501
+
+
+        :return: The float_item of this TypeHolderExample.  # noqa: E501
+        :rtype: float
+        """
+        return self._float_item
+
+    @float_item.setter
+    def float_item(self, float_item):
+        """Sets the float_item of this TypeHolderExample.
+
+
+        :param float_item: The float_item of this TypeHolderExample.  # noqa: E501
+        :type: float
+        """
+        if float_item is None:
+            raise ValueError("Invalid value for `float_item`, must not be `None`")  # noqa: E501
+
+        self._float_item = float_item
+
     @property
     def integer_item(self):
         """Gets the integer_item of this TypeHolderExample.  # noqa: E501