.findExtensionByNumber(type, typeId);
final ExtensionRegistry.ExtensionInfo extension = ((ExtensionRegistry) extensionRegistry) .findExtensionByNumber(type, fieldNumber); if (extension == null) { field = null;
/** * Calls {@code parent.newBuilderForField()} or uses the * {@code ExtensionRegistry} to find an appropriate builder, depending * on what type is being tested. */ private Message.Builder newBuilderForField( Message.Builder parent, Descriptors.FieldDescriptor field) { if (extensionRegistry == null) { return parent.newBuilderForField(field); } else { ExtensionRegistry.ExtensionInfo extension = extensionRegistry.findExtensionByNumber(field.getContainingType(), field.getNumber()); Assert.assertNotNull(extension); Assert.assertNotNull(extension.defaultInstance); return extension.defaultInstance.newBuilderForType(); } }