| // Protocol Buffers - Google's data interchange format |
| // Copyright 2008 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; |
| |
| import static com.google.protobuf.ExtensionRegistryLite.EMPTY_REGISTRY_LITE; |
| |
| /** |
| * A factory object to create instances of {@link ExtensionRegistryLite}. |
| * |
| * <p> |
| * This factory detects (via reflection) if the full (non-Lite) protocol buffer libraries |
| * are available, and if so, the instances returned are actually {@link ExtensionRegistry}. |
| */ |
| final class ExtensionRegistryFactory { |
| |
| static final String FULL_REGISTRY_CLASS_NAME = "com.google.protobuf.ExtensionRegistry"; |
| |
| /* Visible for Testing |
| @Nullable */ |
| static final Class<?> EXTENSION_REGISTRY_CLASS = reflectExtensionRegistry(); |
| |
| /* @Nullable */ |
| static Class<?> reflectExtensionRegistry() { |
| try { |
| return Class.forName(FULL_REGISTRY_CLASS_NAME); |
| } catch (ClassNotFoundException e) { |
| // The exception allocation is potentially expensive on Android (where it can be triggered |
| // many times at start up). Is there a way to ameliorate this? |
| return null; |
| } |
| } |
| |
| /** Construct a new, empty instance. */ |
| public static ExtensionRegistryLite create() { |
| if (EXTENSION_REGISTRY_CLASS != null) { |
| try { |
| return invokeSubclassFactory("newInstance"); |
| } catch (Exception e) { |
| // return a Lite registry. |
| } |
| } |
| return new ExtensionRegistryLite(); |
| } |
| |
| /** Get the unmodifiable singleton empty instance. */ |
| public static ExtensionRegistryLite createEmpty() { |
| if (EXTENSION_REGISTRY_CLASS != null) { |
| try { |
| return invokeSubclassFactory("getEmptyRegistry"); |
| } catch (Exception e) { |
| // return a Lite registry. |
| } |
| } |
| return EMPTY_REGISTRY_LITE; |
| } |
| |
| static boolean isFullRegistry(ExtensionRegistryLite registry) { |
| return EXTENSION_REGISTRY_CLASS != null |
| && EXTENSION_REGISTRY_CLASS.isAssignableFrom(registry.getClass()); |
| } |
| |
| private static final ExtensionRegistryLite invokeSubclassFactory(String methodName) |
| throws Exception { |
| return (ExtensionRegistryLite) EXTENSION_REGISTRY_CLASS |
| .getMethod(methodName).invoke(null); |
| } |
| } |