com.google.devtools.build.lib.query2.engine.BuildFilesFunction.java Source code

Introduction

Here is the source code for com.google.devtools.build.lib.query2.engine.BuildFilesFunction.java

Source

// 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.lib.query2.engine;

import com.google.common.collect.ImmutableList;
import com.google.common.collect.Iterables;
import com.google.devtools.build.lib.collect.CompactHashSet;
import com.google.devtools.build.lib.query2.engine.QueryEnvironment.Argument;
import com.google.devtools.build.lib.query2.engine.QueryEnvironment.ArgumentType;
import com.google.devtools.build.lib.query2.engine.QueryEnvironment.QueryFunction;

import java.util.List;
import java.util.Set;
import java.util.concurrent.ForkJoinPool;

/**
 * A buildfiles(x) query expression, which computes the set of BUILD files and
 * subincluded files for each target in set x.  The result is unordered.  This
 * operator is typically used for determinining what files or packages to check
 * out.
 *
 * <pre>expr ::= BUILDFILES '(' expr ')'</pre>
 */
class BuildFilesFunction implements QueryFunction {
    BuildFilesFunction() {
    }

    @Override
    public String getName() {
        return "buildfiles";
    }

    @Override
    public <T> void eval(final QueryEnvironment<T> env, VariableContext<T> context,
            final QueryExpression expression, List<Argument> args, final Callback<T> callback)
            throws QueryException, InterruptedException {
        env.eval(args.get(0).getExpression(), context, new ThreadSafeCallback<T>() {
            @Override
            public void process(Iterable<T> partialResult) throws QueryException, InterruptedException {
                Set<T> result = CompactHashSet.create();
                Iterables.addAll(result, partialResult);
                callback.process(env.getBuildFiles(expression, result, /* BUILD */ true, /* subinclude */ true,
                        /* load */ true));
            }
        });
    }

    @Override
    public <T> void parEval(QueryEnvironment<T> env, VariableContext<T> context, QueryExpression expression,
            List<Argument> args, ThreadSafeCallback<T> callback, ForkJoinPool forkJoinPool)
            throws QueryException, InterruptedException {
        // 'eval' is written in such a way that it enables parallel evaluation of 'expression'.
        eval(env, context, expression, args, callback);
    }

    @Override
    public int getMandatoryArguments() {
        return 1;
    }

    @Override
    public List<ArgumentType> getArgumentTypes() {
        return ImmutableList.of(ArgumentType.EXPRESSION);
    }
}