com.facebook.buck.jvm.java.JavaLibraryClasspathProvider.java Source code

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Here is the source code for com.facebook.buck.jvm.java.JavaLibraryClasspathProvider.java

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/*
 * Copyright 2014-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.jvm.java;

import com.facebook.buck.rules.BuildRule;
import com.facebook.buck.rules.ExportDependencies;
import com.facebook.buck.rules.SourcePath;
import com.facebook.buck.rules.SourcePathResolver;
import com.google.common.collect.FluentIterable;
import com.google.common.collect.ImmutableSet;
import com.google.common.collect.Sets;

import java.nio.file.Path;
import java.util.Optional;

public class JavaLibraryClasspathProvider {

    private JavaLibraryClasspathProvider() {
    }

    public static ImmutableSet<Path> getOutputClasspathJars(JavaLibrary javaLibraryRule,
            SourcePathResolver resolver, Optional<SourcePath> outputJar) {
        ImmutableSet.Builder<Path> outputClasspathBuilder = ImmutableSet.builder();
        Iterable<JavaLibrary> javaExportedLibraryDeps;
        if (javaLibraryRule instanceof ExportDependencies) {
            javaExportedLibraryDeps = getJavaLibraryDeps(((ExportDependencies) javaLibraryRule).getExportedDeps());
        } else {
            javaExportedLibraryDeps = Sets.newHashSet();
        }

        for (JavaLibrary rule : javaExportedLibraryDeps) {
            outputClasspathBuilder.addAll(rule.getOutputClasspaths());
        }

        if (outputJar.isPresent()) {
            outputClasspathBuilder.add(resolver.getAbsolutePath(outputJar.get()));
        }

        return outputClasspathBuilder.build();
    }

    public static ImmutableSet<JavaLibrary> getTransitiveClasspathDeps(JavaLibrary javaLibrary) {
        ImmutableSet.Builder<JavaLibrary> classpathDeps = ImmutableSet.builder();

        classpathDeps.addAll(getClasspathDeps(javaLibrary.getDepsForTransitiveClasspathEntries()));

        // Only add ourselves to the classpath if there's a jar to be built or if we're a maven dep.
        if (javaLibrary.getPathToOutput() != null || javaLibrary.getMavenCoords().isPresent()) {
            classpathDeps.add(javaLibrary);
        }

        // Or if there are exported dependencies, to be consistent with getTransitiveClasspaths.
        if (javaLibrary instanceof ExportDependencies
                && !((ExportDependencies) javaLibrary).getExportedDeps().isEmpty()) {
            classpathDeps.add(javaLibrary);
        }

        return classpathDeps.build();
    }

    static FluentIterable<JavaLibrary> getJavaLibraryDeps(Iterable<BuildRule> deps) {
        return FluentIterable.from(deps).filter(JavaLibrary.class);
    }

    /**
     * Include the classpath entries from all JavaLibraryRules that have a direct line of lineage
     * to this rule through other JavaLibraryRules. For example, in the following dependency graph:
     *
     *        A
     *      /   \
     *     B     C
     *    / \   / \
     *    D E   F G
     *
     * If all of the nodes correspond to BuildRules that implement JavaLibraryRule except for
     * B (suppose B is a Genrule), then A's classpath will include C, F, and G, but not D and E.
     * This is because D and E are used to generate B, but do not contribute .class files to things
     * that depend on B. However, if C depended on E as well as F and G, then E would be included in
     * A's classpath.
     */
    public static ImmutableSet<JavaLibrary> getClasspathDeps(Iterable<BuildRule> deps) {
        ImmutableSet.Builder<JavaLibrary> classpathDeps = ImmutableSet.builder();
        for (BuildRule dep : deps) {
            if (dep instanceof HasClasspathEntries) {
                classpathDeps.addAll(((HasClasspathEntries) dep).getTransitiveClasspathDeps());
            }
        }
        return classpathDeps.build();
    }

    /**
     * Given libraries that may contribute classpaths, visit them and collect the classpaths.
     *
     * This is used to generate transitive classpaths from library discovered in a previous traversal.
     */
    public static ImmutableSet<Path> getClasspathsFromLibraries(Iterable<JavaLibrary> libraries) {
        ImmutableSet.Builder<Path> classpathEntries = ImmutableSet.builder();
        for (JavaLibrary library : libraries) {
            classpathEntries.addAll(library.getImmediateClasspaths());
        }
        return classpathEntries.build();
    }
}