| /* |
| * Copyright 2013-present Facebook, Inc. |
| * |
| * 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 com.facebook.buck.rules.coercer; |
| |
| import com.facebook.buck.io.ProjectFilesystem; |
| import com.facebook.buck.model.Pair; |
| import com.facebook.buck.parser.BuildTargetParser; |
| import com.google.common.base.Optional; |
| |
| import java.nio.file.Path; |
| import java.util.Collection; |
| import java.util.Iterator; |
| |
| /** |
| * Coerces from a 2-element collection into a pair. |
| */ |
| public class PairTypeCoercer<FIRST, SECOND> implements TypeCoercer<Pair<FIRST, SECOND>> { |
| private TypeCoercer<FIRST> firstTypeCoercer; |
| private TypeCoercer<SECOND> secondTypeCoercer; |
| |
| public PairTypeCoercer( |
| TypeCoercer<FIRST> firstTypeCoercer, TypeCoercer<SECOND> secondTypeCoercer) { |
| this.firstTypeCoercer = firstTypeCoercer; |
| this.secondTypeCoercer = secondTypeCoercer; |
| } |
| |
| @SuppressWarnings("unchecked") |
| @Override |
| public Class<Pair<FIRST, SECOND>> getOutputClass() { |
| return (Class<Pair<FIRST, SECOND>>) (Class<?>) Pair.class; |
| } |
| |
| @Override |
| public boolean hasElementClass(Class<?>... types) { |
| return firstTypeCoercer.hasElementClass(types) || secondTypeCoercer.hasElementClass(types); |
| } |
| |
| @Override |
| public Optional<Pair<FIRST, SECOND>> getOptionalValue() { |
| return Optional.absent(); |
| } |
| |
| @Override |
| public void traverse(Pair<FIRST, SECOND> object, Traversal traversal) { |
| firstTypeCoercer.traverse(object.getFirst(), traversal); |
| secondTypeCoercer.traverse(object.getSecond(), traversal); |
| } |
| |
| @Override |
| public Pair<FIRST, SECOND> coerce( |
| BuildTargetParser buildTargetParser, |
| ProjectFilesystem filesystem, |
| Path pathRelativeToProjectRoot, |
| Object object) |
| throws CoerceFailedException { |
| if (object instanceof Collection) { |
| Collection<?> collection = (Collection<?>) object; |
| if (collection.size() != 2) { |
| throw CoerceFailedException.simple( |
| object, |
| getOutputClass(), |
| "input collection should have 2 elements"); |
| } |
| Iterator<?> iterator = collection.iterator(); |
| FIRST first = firstTypeCoercer.coerce( |
| buildTargetParser, |
| filesystem, |
| pathRelativeToProjectRoot, |
| iterator.next()); |
| SECOND second = secondTypeCoercer.coerce( |
| buildTargetParser, |
| filesystem, |
| pathRelativeToProjectRoot, |
| iterator.next()); |
| return new Pair<>(first, second); |
| } else { |
| throw CoerceFailedException.simple( |
| object, |
| getOutputClass(), |
| "input object should be a 2-element collection"); |
| } |
| } |
| } |