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 * 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

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 *

 * 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,

 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

 *

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 */

/**

 * @test

 * @bug 8176537

 * @summary Check JDK modules have no qualified export to any upgradeable module

 * @modules java.base/jdk.internal.module

 * @run main JdkQualifiedExportTest

 */

import jdk.internal.module.ModuleHashes;

import jdk.internal.module.ModuleInfo;

import java.io.IOException;

import java.io.InputStream;

import java.io.UncheckedIOException;

import java.lang.module.Configuration;

import java.lang.module.ModuleDescriptor;

import java.lang.module.ModuleDescriptor.Exports;

import java.lang.module.ModuleDescriptor.Opens;

import java.lang.module.ModuleFinder;

import java.lang.module.ModuleReference;

import java.util.Collections;

import java.util.Comparator;

import java.util.HashMap;

import java.util.HashSet;

import java.util.Map;

import java.util.Set;

public class JdkQualifiedExportTest {

    public static void main(String... args) {

        // check all system modules

        ModuleFinder.ofSystem().findAll()

                    .stream()

                    .map(ModuleReference::descriptor)

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

                    .forEach(JdkQualifiedExportTest::check);

    }

    static void check(ModuleDescriptor md) {

        // skip checking if this is an upgradeable module

        if (!HashedModules.contains(md.name())) {

            return;

        }

        checkExports(md);

        checkOpens(md);

    }

    static Set<String> KNOWN_EXCEPTIONS =

        Set.of("jdk.internal.vm.ci/jdk.vm.ci.services",

               "jdk.internal.vm.ci/jdk.vm.ci.runtime",

               "jdk.jsobject/jdk.internal.netscape.javascript.spi");

    static void checkExports(ModuleDescriptor md) {

        // build a map of upgradeable module to Exports that are qualified to it

        // skip the qualified exports

        Map<String, Set<Exports>> targetToExports = new HashMap<>();

        md.exports().stream()

          .filter(Exports::isQualified)

          .forEach(e -> e.targets().stream()

                         .filter(mn -> accept(md, mn))

                         .forEach(t -> targetToExports.computeIfAbsent(t, _k -> new HashSet<>())

                                                      .add(e)));

        if (targetToExports.size() > 0) {

            String mn = md.name();

            System.err.println(mn);

            targetToExports.entrySet().stream()

                .sorted(Map.Entry.comparingByKey())

                .forEach(e -> {

                    e.getValue().stream()

                     .forEach(exp -> System.err.format("    exports %s to %s%n",

                                                       exp.source(), e.getKey()));

                });

            // no qualified exports to upgradeable modules are expected

            // except the known exception cases

            if (targetToExports.entrySet().stream()

                    .flatMap(e -> e.getValue().stream())

                    .anyMatch(e -> !KNOWN_EXCEPTIONS.contains(mn + "/" + e.source()))) {

                throw new RuntimeException(mn + " can't export package to upgradeable modules");

            }

        }

    }

    static void checkOpens(ModuleDescriptor md) {

        // build a map of upgradeable module to Exports that are qualified to it

        // skip the qualified exports

        Map<String, Set<Opens>> targetToOpens = new HashMap<>();

        md.opens().stream()

            .filter(Opens::isQualified)

            .forEach(e -> e.targets().stream()

                           .filter(mn -> accept(md, mn))

                           .forEach(t -> targetToOpens.computeIfAbsent(t, _k -> new HashSet<>())

                                                      .add(e)));

        if (targetToOpens.size() > 0) {

            String mn = md.name();

            System.err.println(mn);

            targetToOpens.entrySet().stream()

                .sorted(Map.Entry.comparingByKey())

                .forEach(e -> {

                    e.getValue().stream()

                     .forEach(exp -> System.err.format("    opens %s to %s%n",

                                                       exp.source(), e.getKey()));

                });

            throw new RuntimeException(mn + " can't open package to upgradeable modules");

        }

    }

    /**

     * Returns true if target is an upgradeable module but not required

     * by the source module directly and indirectly.

     */

    private static boolean accept(ModuleDescriptor source, String target) {

        if (HashedModules.contains(target))

            return false;

        if (!ModuleFinder.ofSystem().find(target).isPresent())

            return false;

        Configuration cf = Configuration.empty().resolve(ModuleFinder.of(),

                                                         ModuleFinder.ofSystem(),

                                                         Set.of(source.name()));

        return !cf.findModule(target).isPresent();

    }

    private static class HashedModules {

        static Set<String> HASHED_MODULES = hashedModules();

        static Set<String> hashedModules() {

            Module javaBase = Object.class.getModule();

            try (InputStream in = javaBase.getResourceAsStream("module-info.class")) {

                ModuleInfo.Attributes attrs = ModuleInfo.read(in, null);

                ModuleHashes hashes = attrs.recordedHashes();

                if (hashes == null)

                    return Collections.emptySet();

                Set<String> names = new HashSet<>(hashes.names());

                names.add(javaBase.getName());

                return names;

            } catch (IOException e) {

                throw new UncheckedIOException(e);

            }

        }

        /*

         * Returns true if the named module is tied with java.base,

         * i.e. non-upgradeable

         */

        static boolean contains(String mn) {

            return HASHED_MODULES.contains(mn);

        }

    }

}