Java tutorial
/* * Copyright 2018-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.core.model.targetgraph.impl; import com.facebook.buck.core.cell.CellPathResolver; import com.facebook.buck.core.description.BaseDescription; import com.facebook.buck.core.description.impl.DescriptionCache; import com.facebook.buck.core.exceptions.HumanReadableException; import com.facebook.buck.core.model.BuildTarget; import com.facebook.buck.core.model.Flavor; import com.facebook.buck.core.model.RuleType; import com.facebook.buck.core.model.targetgraph.NodeCopier; import com.facebook.buck.core.model.targetgraph.TargetNode; import com.facebook.buck.core.util.immutables.BuckStyleImmutable; import com.facebook.buck.io.filesystem.ProjectFilesystem; import com.facebook.buck.rules.visibility.VisibilityChecker; import com.facebook.buck.rules.visibility.VisibilityPattern; import com.facebook.buck.versions.Version; import com.google.common.collect.ImmutableMap; import com.google.common.collect.ImmutableSet; import com.google.common.collect.ImmutableSortedSet; import com.google.common.collect.Sets; import java.nio.file.Path; import java.util.Optional; import java.util.Set; import org.immutables.value.Value; /** * A {@link TargetNode} represents a node in the target graph which is created by the {@link * com.facebook.buck.parser.Parser} as a result of parsing BUCK files in a project. It is * responsible for processing the raw (python) inputs of a build rule, and gathering any build * targets and paths referenced from those inputs. */ @BuckStyleImmutable @Value.Immutable(builder = false, prehash = true) abstract class AbstractImmutableTargetNode<T> implements TargetNode<T> { @Value.Parameter @Override public abstract BuildTarget getBuildTarget(); @Value.Parameter @Override public abstract NodeCopier getNodeCopier(); // TODO(#22139496): Currently, `Descriptions` don't implement content equality, so we exclude it // from the `equals`/`hashCode` implementation of `TargetNode`. This should be fine, as we // already rely on restarting the daemon if the descriptions change in any meaningful way to // maintain parser cache integrity. @Value.Parameter @Value.Auxiliary @Override public abstract BaseDescription<T> getDescription(); @Value.Parameter @Override public abstract T getConstructorArg(); @Value.Parameter @Override public abstract ProjectFilesystem getFilesystem(); @Value.Parameter @Override public abstract ImmutableSet<Path> getInputs(); @Value.Parameter @Override public abstract ImmutableSet<BuildTarget> getDeclaredDeps(); @Value.Parameter @Override public abstract ImmutableSortedSet<BuildTarget> getExtraDeps(); /** * BuildTargetPaths which, when changed, may change the BuildRules produced by this TargetNode, * but whose steps don't need executing in order to build this TargetNode's BuildRules. * * <p>A TargetNode may require metadata from other targets in order to be constructed, but may not * actually require those targets' build output. For example, some targets may execute queries * against the TargetGraph (e.g. detecting the names of rules of a certain type) but don't use the * output of those detected rules. */ @Value.Parameter @Override public abstract ImmutableSortedSet<BuildTarget> getTargetGraphOnlyDeps(); @Value.Parameter @Override public abstract CellPathResolver getCellNames(); @Value.Parameter @Override public abstract ImmutableSet<VisibilityPattern> getVisibilityPatterns(); @Value.Parameter @Override public abstract ImmutableSet<VisibilityPattern> getWithinViewPatterns(); @Value.Parameter @Override public abstract Optional<ImmutableMap<BuildTarget, Version>> getSelectedVersions(); @Override @Value.Lazy public VisibilityChecker getVisibilityChecker() { return new VisibilityChecker(this, getVisibilityPatterns(), getWithinViewPatterns()); } /** @return all targets which must be built before this one can be. */ @Override public Set<BuildTarget> getBuildDeps() { return Sets.union(getDeclaredDeps(), getExtraDeps()); } /** * @return all targets which must be present in the TargetGraph before this one can be transformed * into a BuildRule. */ @Override public Set<BuildTarget> getParseDeps() { return Sets.union(getBuildDeps(), getTargetGraphOnlyDeps()); } @Override public boolean isVisibleTo(TargetNode<?> viewer) { return getVisibilityChecker().isVisibleTo(viewer); } @Override public void isVisibleToOrThrow(TargetNode<?> viewer) { if (!isVisibleTo(viewer)) { throw new HumanReadableException( "%s depends on %s, which is not visible. More info at:\nhttps://buckbuild.com/concept/visibility.html", viewer, getBuildTarget()); } } @Override public RuleType getRuleType() { return DescriptionCache.getRuleType(getDescription()); } @Override public int compareTo(TargetNode<?> o) { return getBuildTarget().compareTo(o.getBuildTarget()); } @Override public final String toString() { return getBuildTarget().getFullyQualifiedName(); } @Override public TargetNode<T> copy() { return ImmutableTargetNode.copyOf(this); } @Override public TargetNode<T> copyWithFlavors(ImmutableSet<Flavor> flavors) { return getNodeCopier().copyNodeWithFlavors(ImmutableTargetNode.copyOf(this), flavors); } @Override public TargetNode<T> withFlavors(ImmutableSet<Flavor> flavors) { return ImmutableTargetNode.copyOf(this).withBuildTarget(getBuildTarget().withFlavors(flavors)); } }