1 // Copyright 2017 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.common.collect.ImmutableList; 18 import java.lang.annotation.ElementType; 19 import java.lang.annotation.Inherited; 20 import java.lang.annotation.Retention; 21 import java.lang.annotation.RetentionPolicy; 22 import java.lang.annotation.Target; 23 import java.time.Duration; 24 import java.util.List; 25 26 /** 27 * Applied to an {@link OptionsBase} subclass to indicate that all of its options fields have types 28 * chosen from {@link #coreTypes}. Any subclasses of the class to which it's applied must also 29 * satisfy the same property. 30 * 31 * <p>Options classes with this annotation are serializable and deeply immutable, except that the 32 * fields of the options class can be reassigned (although this is bad practice). 33 * 34 * <p>Note that {@link Option#allowMultiple} is not allowed for options in classes with this 35 * annotation, since their type is {@link List}. 36 */ 37 @Target({ElementType.TYPE}) 38 @Retention(RetentionPolicy.RUNTIME) 39 @Inherited 40 public @interface UsesOnlyCoreTypes { 41 42 /** 43 * These are the core options field types. They all have default converters, are deeply immutable, 44 * and are serializable. 45 * 46 * Lists are not considered core types, so {@link Option#allowMultiple} options are not permitted. 47 */ 48 public static final ImmutableList<Class<?>> CORE_TYPES = ImmutableList.of( 49 // 1:1 correspondence with Converters.DEFAULT_CONVERTERS. 50 String.class, 51 int.class, 52 long.class, 53 double.class, 54 boolean.class, 55 TriState.class, 56 Void.class, 57 Duration.class 58 ); 59 } 60
