1 // Copyright 2014 The Bazel Authors. All rights reserved. 2 // 3 // Licensed under the Apache License, Version 2.0 (the "License"); 4 // you may not use this file except in compliance with the License. 5 // You may obtain a copy of the License at 6 // 7 // http://www.apache.org/licenses/LICENSE-2.0 8 // 9 // Unless required by applicable law or agreed to in writing, software 10 // distributed under the License is distributed on an "AS IS" BASIS, 11 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 12 // See the License for the specific language governing permissions and 13 // limitations under the License. 14 15 package com.google.devtools.common.options; 16 17 import com.google.devtools.common.options.Converters.BooleanConverter; 18 19 /** 20 * Converter that can also convert from booleans and enumerations. 21 * 22 * <p> This is able to additionally convert from the standard set of 23 * boolean string values. If there is an overlap in values, those from 24 * the underlying enumeration will be taken. 25 */ 26 public abstract class BoolOrEnumConverter<T extends Enum<T>> extends EnumConverter<T>{ 27 private T falseValue; 28 private T trueValue; 29 30 /** 31 * You *must* implement a zero-argument constructor that delegates 32 * to this constructor, passing in the appropriate parameters. This 33 * comes from the base {@link EnumConverter} class. 34 * 35 * @param enumType The type of your enumeration; usually a class literal 36 * like MyEnum.class 37 * @param typeName The intuitive name of your enumeration, for example, the 38 * type name for CompilationMode might be "compilation mode". 39 * @param trueValue The enumeration value to associate with {@code true}. 40 * @param falseValue The enumeration value to associate with {@code false}. 41 */ 42 protected BoolOrEnumConverter(Class<T> enumType, String typeName, T trueValue, T falseValue) { 43 super(enumType, typeName); 44 this.trueValue = trueValue; 45 this.falseValue = falseValue; 46 } 47 48 @Override 49 public T convert(String input) throws OptionsParsingException { 50 try { 51 return super.convert(input); 52 } catch (OptionsParsingException eEnum) { 53 try { 54 BooleanConverter booleanConverter = new BooleanConverter(); 55 boolean value = booleanConverter.convert(input); 56 return value ? trueValue : falseValue; 57 } catch (OptionsParsingException eBoolean) { 58 throw eEnum; 59 } 60 } 61 } 62 } 63
