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Diffstat (limited to 'Tools/Scripts/webkitpy/common/lru_cache.py')
-rw-r--r-- | Tools/Scripts/webkitpy/common/lru_cache.py | 134 |
1 files changed, 0 insertions, 134 deletions
diff --git a/Tools/Scripts/webkitpy/common/lru_cache.py b/Tools/Scripts/webkitpy/common/lru_cache.py deleted file mode 100644 index 02a3d1c35..000000000 --- a/Tools/Scripts/webkitpy/common/lru_cache.py +++ /dev/null @@ -1,134 +0,0 @@ -# Copyright (C) 2011 Google Inc. All rights reserved. -# -# Redistribution and use in source and binary forms, with or without -# modification, are permitted provided that the following conditions are -# met: -# -# * Redistributions of source code must retain the above copyright -# notice, this list of conditions and the following disclaimer. -# * Redistributions in binary form must reproduce the above -# copyright notice, this list of conditions and the following disclaimer -# in the documentation and/or other materials provided with the -# distribution. -# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS -# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT -# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR -# A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT -# OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, -# SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT -# LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, -# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY -# THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT -# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE -# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. - - -class Node(): - def __init__(self, key, value): - self.key = key - self.value = value - self.prev = None - self.next = None - - -class LRUCache(): - """An implementation of Least Recently Used (LRU) Cache.""" - - def __init__(self, capacity): - """Initializes a lru cache with the given capacity. - - Args: - capacity: The capacity of the cache. - """ - assert capacity > 0, "capacity (%s) must be greater than zero." % capacity - self._first = None - self._last = None - self._dict = {} - self._capacity = capacity - - def __setitem__(self, key, value): - if key in self._dict: - self.__delitem__(key) - if not self._first: - self._one_node(key, value) - return - if len(self._dict) >= self._capacity: - del self._dict[self._last.key] - if self._capacity == 1: - self._one_node(key, value) - return - self._last = self._last.next - self._last.prev = None - node = Node(key, value) - node.prev = self._first - self._first.next = node - self._first = node - self._dict[key] = node - - def _one_node(self, key, value): - node = Node(key, value) - self._dict[key] = node - self._first = node - self._last = node - - def __getitem__(self, key): - if not self._first: - raise KeyError(str(key)) - if self._first.key == key: - return self._first.value - - if self._last.key == key: - next_last = self._last.next - next_last.prev = None - next_first = self._last - next_first.prev = self._first - next_first.next = None - self._first.next = next_first - self._first = next_first - self._last = next_last - return self._first.value - - node = self._dict[key] - node.next.prev = node.prev - node.prev.next = node.next - node.prev = self._first - node.next = None - self._first.next = node - self._first = node - return self._first.value - - def __delitem__(self, key): - node = self._dict[key] - del self._dict[key] - if self._first is self._last: - self._last = None - self._first = None - return - if self._first is node: - self._first = node.prev - self._first.next = None - return - if self._last is node: - self._last = node.next - self._last.prev = None - return - node.next.prev = node.prev - node.prev.next = node.next - - def __len__(self): - return len(self._dict) - - def __contains__(self, key): - return key in self._dict - - def __iter__(self): - return iter(self._dict) - - def items(self): - return [(key, node.value) for key, node in self._dict.items()] - - def values(self): - return [node.value for node in self._dict.values()] - - def keys(self): - return self._dict.keys() |