| // Copyright 2022 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 static com.google.common.base.Preconditions.checkNotNull; |
| |
| import com.google.common.annotations.VisibleForTesting; |
| import com.google.common.base.Function; |
| import com.google.devtools.build.lib.bugreport.BugReport; |
| import javax.annotation.Nullable; |
| |
| /** |
| * An Map-like result of getting Skyframe dependencies via {@link |
| * SkyFunction.Environment#getValuesAndExceptions}. Callers can use the {@link #get} and {@link |
| * #getOrThrow} methods to obtain elements by key. |
| * |
| * <p>Note that a {@link SkyFunction} cannot guarantee that {@link |
| * SkyFunction.Environment#valuesMissing} will be true upon receipt of a {@code |
| * SkyframeLookupResult}. The elements must all be fetched. If {@link #get} or {@link #getOrThrow} |
| * returns {@code null}, only then will {@link SkyFunction.Environment#valuesMissing} be guaranteed |
| * to return true. |
| */ |
| public class SkyframeLookupResult { |
| private final Runnable valuesMissingCallback; |
| private final Function<SkyKey, ValueOrUntypedException> valuesOrExceptions; |
| |
| @VisibleForTesting |
| public SkyframeLookupResult( |
| Runnable valuesMissingCallback, |
| Function<SkyKey, ValueOrUntypedException> valuesOrExceptions) { |
| this.valuesMissingCallback = checkNotNull(valuesMissingCallback); |
| this.valuesOrExceptions = checkNotNull(valuesOrExceptions); |
| } |
| |
| /** |
| * Returns a direct dependency. If the dependency is not in the set of already evaluated direct |
| * dependencies, returns {@code null}. Also returns {@code null} if the dependency has already |
| * been evaluated and found to be in error. In either of these cases, {@link |
| * SkyFunction.Environment#valuesMissing} will subsequently return true. |
| */ |
| @Nullable |
| public SkyValue get(SkyKey skyKey) { |
| return getOrThrow(skyKey, null, null, null); |
| } |
| |
| /** |
| * Returns a direct dependency. If the dependency is not in the set of already evaluated direct |
| * dependencies, returns {@code null}. If the dependency has already been evaluated and found to |
| * be in error, throws the exception coming from the error, so long as the exception is of one of |
| * the specified types. SkyFunction implementations may use this method to catch and rethrow a |
| * more informative exception or to continue evaluation. The caller must specify the exception |
| * type(s) that might be thrown using the {@code exceptionClass} argument(s). If the dependency's |
| * exception is not an instance of {@code exceptionClass}, {@code null} is returned. In this case, |
| * {@link SkyFunction.Environment#valuesMissing} will subsequently return true. |
| * |
| * <p>The exception class given cannot be a supertype or a subtype of {@link RuntimeException}, or |
| * a subtype of {@link InterruptedException}. See {@link |
| * SkyFunctionException#validateExceptionType} for details. |
| */ |
| @Nullable |
| public <E1 extends Exception> SkyValue getOrThrow(SkyKey skyKey, Class<E1> exceptionClass) |
| throws E1 { |
| return getOrThrow(skyKey, exceptionClass, null, null); |
| } |
| |
| /** |
| * Similar to {@link getOrThrow} one exceptionClass version, but take two exceptionClass |
| * parameters. |
| */ |
| @Nullable |
| public <E1 extends Exception, E2 extends Exception> SkyValue getOrThrow( |
| SkyKey skyKey, Class<E1> exceptionClass1, Class<E2> exceptionClass2) throws E1, E2 { |
| return getOrThrow(skyKey, exceptionClass1, exceptionClass2, null); |
| } |
| |
| /** |
| * Similar to {@link getOrThrow} one exceptionClass version, but take three exceptionClass |
| * parameters. |
| */ |
| @Nullable |
| public <E1 extends Exception, E2 extends Exception, E3 extends Exception> SkyValue getOrThrow( |
| SkyKey skyKey, |
| @Nullable Class<E1> exceptionClass1, |
| @Nullable Class<E2> exceptionClass2, |
| @Nullable Class<E3> exceptionClass3) |
| throws E1, E2, E3 { |
| ValueOrUntypedException voe = valuesOrExceptions.apply(skyKey); |
| if (voe == null) { |
| BugReport.sendBugReport( |
| new IllegalStateException( |
| "ValueOrUntypedException " + skyKey + " was missing, this should never happen")); |
| return null; |
| } |
| SkyValue value = voe.getValue(); |
| if (value != null) { |
| return value; |
| } |
| Exception e = voe.getException(); |
| if (e != null) { |
| if (exceptionClass1 != null && exceptionClass1.isInstance(e)) { |
| throw exceptionClass1.cast(e); |
| } |
| if (exceptionClass2 != null && exceptionClass2.isInstance(e)) { |
| throw exceptionClass2.cast(e); |
| } |
| if (exceptionClass3 != null && exceptionClass3.isInstance(e)) { |
| throw exceptionClass3.cast(e); |
| } |
| } |
| valuesMissingCallback.run(); |
| return null; |
| } |
| } |