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

 *

 * This code is free software; you can redistribute it and/or modify it

 * 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

 * by Oracle in the LICENSE file that accompanied this code.

 *

 * 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,

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

 *

 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

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package com.sun.tools.jdeprscan;

import java.util.ArrayList;

import java.util.Collection;

import java.util.Comparator;

import java.util.HashMap;

import java.util.HashSet;

import java.util.List;

import java.util.Map;

import java.util.Set;

import javax.annotation.processing.AbstractProcessor;

import javax.annotation.processing.Messager;

import javax.annotation.processing.ProcessingEnvironment;

import javax.annotation.processing.RoundEnvironment;

import javax.annotation.processing.SupportedAnnotationTypes;

import javax.annotation.processing.SupportedSourceVersion;

import javax.lang.model.element.Element;

import javax.lang.model.element.ElementKind;

import javax.lang.model.element.Modifier;

import javax.lang.model.element.PackageElement;

import javax.tools.Diagnostic;

@SupportedAnnotationTypes("*")

public class TraverseProc extends AbstractProcessor {

    Elements elements;

    Messager messager;

    final List<String> moduleRoots;

    Map<PackageElement, List<TypeElement>> publicTypes;

    TraverseProc(List<String> roots) {

        moduleRoots = roots;

    }

    @Override

    public void init(ProcessingEnvironment pe) {

        super.init(pe);

        elements = pe.getElementUtils();

        messager = pe.getMessager();

    }

    @Override

    public boolean process(Set<? extends TypeElement> annotations, RoundEnvironment roundEnv) {

        if (roundEnv.processingOver()) {

            return false;

        }

        Set<ModuleElement> modules = new HashSet<>();

        for (String mname : moduleRoots) {

            ModuleElement me = elements.getModuleElement(mname);

            if (me == null) {

                messager.printMessage(Diagnostic.Kind.ERROR,

                                      String.format("module %s not found%n", mname));

            } else {

                modules.addAll(findModules(me));

            }

        }

        Set<PackageElement> packages = findPackages(modules);

        publicTypes = findPublicTypes(packages);

        return true;

    }

    void printPublicTypes() {

        printPublicTypes(publicTypes);

    }

    public Map<PackageElement, List<TypeElement>> getPublicTypes() {

        return publicTypes;

    }

    void printPublicTypes(Map<PackageElement, List<TypeElement>> types) {

        System.out.println("All public types:");

        types.entrySet().stream()

             .sorted(Comparator.comparing(e -> e.getKey().toString()))

             .forEach(e -> {

                 System.out.println("  " + e.getKey());

                 e.getValue().stream()

                         .sorted(Comparator.comparing(TypeElement::toString))

                         .forEach(t -> System.out.println("    " + t));

             });

        System.out.println();

        System.out.flush();

    }

    Set<ModuleElement> findModules(ModuleElement root) {

        return findModules0(root, new HashSet<>(), 0);

    }

    Set<ModuleElement> findModules0(ModuleElement m, Set<ModuleElement> set, int nesting) {

        set.add(m);

        for (ModuleElement.Directive dir : m.getDirectives()) {

            if (dir.getKind() == ModuleElement.DirectiveKind.REQUIRES) {

                ModuleElement.RequiresDirective req = (ModuleElement.RequiresDirective)dir;

                findModules0(req.getDependency(), set, nesting + 1);

            }

        }

        return set;

    }

    Set<PackageElement> findPackages(Collection<ModuleElement> mods) {

        Set<PackageElement> set = new HashSet<>();

        for (ModuleElement m : mods) {

            for (ModuleElement.Directive dir : m.getDirectives()) {

                if (dir.getKind() == ModuleElement.DirectiveKind.EXPORTS) { //XXX

                    ModuleElement.ExportsDirective exp = (ModuleElement.ExportsDirective)dir;

                    if (exp.getTargetModules() == null) {

                        set.add(exp.getPackage());

                    }

                }

            }

        }

        return set;

    }

    Map<PackageElement, List<TypeElement>> findPublicTypes(Collection<PackageElement> pkgs) {

        Map<PackageElement, List<TypeElement>> map = new HashMap<>();

        for (PackageElement pkg : pkgs) {

            List<TypeElement> enclosed = new ArrayList<>();

            for (Element e : pkg.getEnclosedElements()) {

                addPublicTypes(enclosed, e);

            }

            map.put(pkg, enclosed);

        }

        return map;

    }

    void addPublicTypes(List<TypeElement> list, Element e) {

        ElementKind kind = e.getKind();

        if ((kind.isClass() || kind.isInterface())

                && e.getModifiers().contains(Modifier.PUBLIC)) {

            list.add((TypeElement)e);

            for (Element enc : e.getEnclosedElements()) {

                addPublicTypes(list, enc);

            }

        }

    }

}