| // Copyright 2014 The Bazel Authors. All rights reserved. |
| // |
| // 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.google.devtools.build.skyframe; |
| |
| import com.google.common.annotations.VisibleForTesting; |
| import javax.annotation.Nullable; |
| |
| /** |
| * Wrapper for a value or the untyped exception thrown when trying to compute it. |
| * |
| * <p>This is an implementation detail of {@link ParallelEvaluator}. It's an abstract class (as |
| * opposed to an interface) to avoid exposing the methods outside the package. |
| */ |
| @VisibleForTesting |
| public abstract class ValueOrUntypedException { |
| /** Returns the stored value, if there was one. */ |
| @Nullable |
| abstract SkyValue getValue(); |
| |
| /** Returns the stored exception, if there was one. */ |
| @Nullable |
| abstract Exception getException(); |
| |
| public static ValueOrUntypedException ofValueUntyped(SkyValue value) { |
| return new ValueOrUntypedExceptionImpl(value); |
| } |
| |
| public static ValueOrUntypedException ofNull() { |
| return ValueOrUntypedExceptionImpl.NULL; |
| } |
| |
| public static ValueOrUntypedException ofExn(Exception e) { |
| return new ValueOrUntypedExceptionExnImpl(e); |
| } |
| |
| private static class ValueOrUntypedExceptionImpl extends ValueOrUntypedException { |
| static final ValueOrUntypedExceptionImpl NULL = new ValueOrUntypedExceptionImpl(null); |
| @Nullable private final SkyValue value; |
| |
| ValueOrUntypedExceptionImpl(@Nullable SkyValue value) { |
| this.value = value; |
| } |
| |
| @Override |
| @Nullable |
| public SkyValue getValue() { |
| return value; |
| } |
| |
| @Override |
| public Exception getException() { |
| return null; |
| } |
| } |
| |
| private static class ValueOrUntypedExceptionExnImpl extends ValueOrUntypedException { |
| private final Exception exception; |
| |
| ValueOrUntypedExceptionExnImpl(Exception exception) { |
| this.exception = exception; |
| } |
| |
| @Override |
| @Nullable |
| public SkyValue getValue() { |
| return null; |
| } |
| |
| @Override |
| public Exception getException() { |
| return exception; |
| } |
| } |
| } |