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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

 *

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 * under the terms of the GNU General Public License version 2 only, as

 * published by the Free Software Foundation.  Oracle designates this

 * particular file as subject to the "Classpath" exception as provided

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 *

 * This code is distributed in the hope that it will be useful, but WITHOUT

 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

 * version 2 for more details (a copy is included in the LICENSE file that

 * accompanied this code).

 *

 * You should have received a copy of the GNU General Public License version

 * 2 along with this work; if not, write to the Free Software Foundation,

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 *

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package com.sun.tools.jdeps;

import java.io.IOException;

import java.io.PrintWriter;

import java.lang.module.ModuleDescriptor;

import java.util.Comparator;

import java.util.HashMap;

import java.util.HashSet;

import java.util.Map;

import java.util.Set;

import java.util.TreeSet;

import java.util.stream.Collectors;

import java.util.stream.Stream;

/**

 * Analyze module dependences and any reference to JDK internal APIs.

 * It can apply transition reduction on the resulting module graph.

 *

 * The result prints one line per module it depends on

 * one line per JDK internal API package it references:

 *     $MODULE[/$PACKAGE]

 *

 */

public class ModuleExportsAnalyzer extends DepsAnalyzer {

    // source archive to its dependences and JDK internal APIs it references

    private final Map<Archive, Map<Archive,Set<String>>> deps = new HashMap<>();

    private final boolean showJdkInternals;

    private final boolean reduced;

    private final PrintWriter writer;

    private final String separator;

    public ModuleExportsAnalyzer(JdepsConfiguration config,

                                 JdepsFilter filter,

                                 boolean showJdkInternals,

                                 boolean reduced,

                                 PrintWriter writer,

                                 String separator) {

        super(config, filter, null,

              Analyzer.Type.PACKAGE,

              false /* all classes */);

        this.showJdkInternals = showJdkInternals;

        this.reduced = reduced;

        this.writer = writer;

        this.separator = separator;

    }

    @Override

    public boolean run() throws IOException {

        // analyze dependences

        boolean rc = super.run();

        // A visitor to record the module-level dependences as well as

        // use of JDK internal APIs

        Analyzer.Visitor visitor = (origin, originArchive, target, targetArchive) -> {

            Set<String> jdkInternals =

                deps.computeIfAbsent(originArchive, _k -> new HashMap<>())

                    .computeIfAbsent(targetArchive, _k -> new HashSet<>());

            Module module = targetArchive.getModule();

            if (showJdkInternals && originArchive.getModule() != module &&

                    module.isJDK() && !module.isExported(target)) {

                // use of JDK internal APIs

                jdkInternals.add(target);

            }

        };

        // visit the dependences

        archives.stream()

            .filter(analyzer::hasDependences)

            .sorted(Comparator.comparing(Archive::getName))

            .forEach(archive -> analyzer.visitDependences(archive, visitor));

        Set<Module> modules = modules();

        if (showJdkInternals) {

            // print modules and JDK internal API dependences

            printDependences(modules);

        } else {

            // print module dependences

            writer.println(modules.stream().map(Module::name).sorted()

                                  .collect(Collectors.joining(separator)));

        }

        return rc;

    }

    private Set<Module> modules() {

        // build module graph

        ModuleGraphBuilder builder = new ModuleGraphBuilder(configuration);

        Module root = new RootModule("root");

        builder.addModule(root);

        // find named module dependences

        dependenceStream()

            .flatMap(map -> map.keySet().stream())

            .filter(m -> m.getModule().isNamed()

                && !configuration.rootModules().contains(m))

            .map(Archive::getModule)

            .forEach(m -> builder.addEdge(root, m));

        // build module dependence graph

        // if reduced is set, apply transition reduction

        Graph<Module> g = reduced ? builder.reduced() : builder.build();

        return g.adjacentNodes(root);

    }

    private void printDependences(Set<Module> modules) {

        // find use of JDK internals

        Map<Module, Set<String>> jdkinternals = new HashMap<>();

        dependenceStream()

            .flatMap(map -> map.entrySet().stream())

            .filter(e -> e.getValue().size() > 0)

            .forEach(e -> jdkinternals.computeIfAbsent(e.getKey().getModule(),

                                                       _k -> new TreeSet<>())

                                      .addAll(e.getValue()));

        // print modules and JDK internal API dependences

        Stream.concat(modules.stream(), jdkinternals.keySet().stream())

              .sorted(Comparator.comparing(Module::name))

              .distinct()

              .forEach(m -> {

                  if (jdkinternals.containsKey(m)) {

                      jdkinternals.get(m).stream()

                          .forEach(pn -> writer.format("   %s/%s%s", m, pn, separator));

                  } else {

                      writer.format("   %s%s", m, separator);

                  }

              });

    }

    /*

     * Returns a stream of dependence map from an Archive to the set of JDK

     * internal APIs being used.

     */

    private Stream<Map<Archive, Set<String>>> dependenceStream() {

        return deps.keySet().stream()

                   .filter(source -> !source.getModule().isNamed()

                            || configuration.rootModules().contains(source))

                   .map(deps::get);

    }

    private class RootModule extends Module {

        final ModuleDescriptor descriptor;

        RootModule(String name) {

            super(name);

            ModuleDescriptor.Builder builder = ModuleDescriptor.newModule(name);

            this.descriptor = builder.build();

        }

        @Override

        public ModuleDescriptor descriptor() {

            return descriptor;

        }

    }

}