diff options
Diffstat (limited to 'javanano/src/main/java/com/google/protobuf/nano/MapFactories.java')
-rw-r--r-- | javanano/src/main/java/com/google/protobuf/nano/MapFactories.java | 67 |
1 files changed, 67 insertions, 0 deletions
diff --git a/javanano/src/main/java/com/google/protobuf/nano/MapFactories.java b/javanano/src/main/java/com/google/protobuf/nano/MapFactories.java new file mode 100644 index 00000000..98fa4877 --- /dev/null +++ b/javanano/src/main/java/com/google/protobuf/nano/MapFactories.java @@ -0,0 +1,67 @@ +// Protocol Buffers - Google's data interchange format +// Copyright 2013 Google Inc. All rights reserved. +// https://developers.google.com/protocol-buffers/ +// +// 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. +// * Neither the name of Google Inc. nor the names of its +// contributors may be used to endorse or promote products derived from +// this software without specific prior written permission. +// +// 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. + +package com.google.protobuf.nano; + +import java.util.HashMap; +import java.util.Map; + +/** + * Utility class for maps support. + */ +public final class MapFactories { + public static interface MapFactory { + <K, V> Map<K, V> forMap(Map<K, V> oldMap); + } + + // NOTE(liujisi): The factory setter is temporarily marked as package private. + // The way to provide customized implementations of maps for different + // platforms are still under discussion. Mark it as private to avoid exposing + // the API in proto3 alpha release. + /* public */ static void setMapFactory(MapFactory newMapFactory) { + mapFactory = newMapFactory; + } + + public static MapFactory getMapFactory() { + return mapFactory; + } + + private static class DefaultMapFactory implements MapFactory { + public <K, V> Map<K, V> forMap(Map<K, V> oldMap) { + if (oldMap == null) { + return new HashMap<K, V>(); + } + return oldMap; + } + } + private static volatile MapFactory mapFactory = new DefaultMapFactory(); + + private MapFactories() {} +} |