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# Protocol Buffers - Google's data interchange format
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# Copyright 2008 Google Inc. All rights reserved.
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# http://code.google.com/p/protobuf/
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# Redistribution and use in source and binary forms, with or without
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# modification, are permitted provided that the following conditions are
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# * Redistributions of source code must retain the above copyright
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# notice, this list of conditions and the following disclaimer.
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# * Redistributions in binary form must reproduce the above
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# copyright notice, this list of conditions and the following disclaimer
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# in the documentation and/or other materials provided with the
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# * Neither the name of Google Inc. nor the names of its
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# contributors may be used to endorse or promote products derived from
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# this software without specific prior written permission.
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# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
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# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
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# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
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# A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
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# OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
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# SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
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# LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
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# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
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# THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
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# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
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# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
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"""Contains container classes to represent different protocol buffer types.
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This file defines container classes which represent categories of protocol
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buffer field types which need extra maintenance. Currently these categories
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- Repeated scalar fields - These are all repeated fields which aren't
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composite (e.g. they are of simple types like int32, string, etc).
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- Repeated composite fields - Repeated fields which are composite. This
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includes groups and nested messages.
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__author__ = 'petar@google.com (Petar Petrov)'
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class BaseContainer(object):
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"""Base container class."""
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# Minimizes memory usage and disallows assignment to other attributes.
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__slots__ = ['_message_listener', '_values']
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def __init__(self, message_listener):
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message_listener: A MessageListener implementation.
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The RepeatedScalarFieldContainer will call this object's
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TransitionToNonempty() method when it transitions from being empty to
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self._message_listener = message_listener
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def __getitem__(self, key):
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"""Retrieves item by the specified key."""
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return self._values[key]
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"""Returns the number of elements in the container."""
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return len(self._values)
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def __ne__(self, other):
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"""Checks if another instance isn't equal to this one."""
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# The concrete classes should define __eq__.
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return not self == other
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class RepeatedScalarFieldContainer(BaseContainer):
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"""Simple, type-checked, list-like container for holding repeated scalars."""
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# Disallows assignment to other attributes.
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__slots__ = ['_type_checker']
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def __init__(self, message_listener, type_checker):
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message_listener: A MessageListener implementation.
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The RepeatedScalarFieldContainer will call this object's
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TransitionToNonempty() method when it transitions from being empty to
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type_checker: A type_checkers.ValueChecker instance to run on elements
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inserted into this container.
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super(RepeatedScalarFieldContainer, self).__init__(message_listener)
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self._type_checker = type_checker
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def append(self, elem):
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"""Appends a scalar to the list. Similar to list.append()."""
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self._type_checker.CheckValue(elem)
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self._values.append(elem)
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self._message_listener.ByteSizeDirty()
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if len(self._values) == 1:
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self._message_listener.TransitionToNonempty()
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def remove(self, elem):
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"""Removes a scalar from the list. Similar to list.remove()."""
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self._values.remove(elem)
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self._message_listener.ByteSizeDirty()
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def __setitem__(self, key, value):
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"""Sets the item on the specified position."""
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# No need to call TransitionToNonempty(), since if we're able to
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# set the element at this index, we were already nonempty before
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# this method was called.
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self._message_listener.ByteSizeDirty()
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self._type_checker.CheckValue(value)
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self._values[key] = value
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def __eq__(self, other):
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"""Compares the current instance with another one."""
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# Special case for the same type which should be common and fast.
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if isinstance(other, self.__class__):
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return other._values == self._values
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# We are presumably comparing against some other sequence type.
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return other == self._values
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class RepeatedCompositeFieldContainer(BaseContainer):
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"""Simple, list-like container for holding repeated composite fields."""
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# Disallows assignment to other attributes.
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__slots__ = ['_message_descriptor']
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def __init__(self, message_listener, message_descriptor):
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Note that we pass in a descriptor instead of the generated directly,
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since at the time we construct a _RepeatedCompositeFieldContainer we
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haven't yet necessarily initialized the type that will be contained in the
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message_listener: A MessageListener implementation.
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The RepeatedCompositeFieldContainer will call this object's
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TransitionToNonempty() method when it transitions from being empty to
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message_descriptor: A Descriptor instance describing the protocol type
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that should be present in this container. We'll use the
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_concrete_class field of this descriptor when the client calls add().
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super(RepeatedCompositeFieldContainer, self).__init__(message_listener)
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self._message_descriptor = message_descriptor
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"""Adds a new element to the list and returns it."""
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new_element = self._message_descriptor._concrete_class()
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new_element._SetListener(self._message_listener)
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self._values.append(new_element)
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self._message_listener.ByteSizeDirty()
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self._message_listener.TransitionToNonempty()
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def __delitem__(self, key):
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"""Deletes the element on the specified position."""
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self._message_listener.ByteSizeDirty()
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del self._values[key]
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def __eq__(self, other):
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"""Compares the current instance with another one."""
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if not isinstance(other, self.__class__):
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raise TypeError('Can only compare repeated composite fields against '
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'other repeated composite fields.')
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return self._values == other._values
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# TODO(robinson): Implement, document, and test slicing support.
added
removed
python/google/protobuf/internal/containers.py
