/** * Copyright (c) 2008, http://www.snakeyaml.org * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ package org.yaml.snakeyaml.issues.issue311; public enum BooleanEnum { TRUE(true), FALSE(false), UNKNOWN(); private boolean boolValue; private boolean defined; BooleanEnum(boolean p) { boolValue = p; defined = true; } BooleanEnum() { boolValue = false; defined = false; } boolean getBoolValue() { if (!defined) throw new IllegalArgumentException("Undefined has no value"); else return boolValue; } boolean isDefined() { return defined; } }