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 * Copyright (c) 2016, 2017, Oracle and/or its affiliates. All rights reserved.

 * 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.lang.annotation.IncompleteAnnotationException;

import java.util.ArrayList;

import java.util.List;

import java.util.Set;

import java.util.stream.Collectors;

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.ExecutableElement;

import javax.lang.model.element.TypeElement;

import javax.lang.model.type.ArrayType;

import javax.lang.model.type.DeclaredType;

import javax.lang.model.type.ExecutableType;

import javax.lang.model.type.TypeMirror;

import javax.lang.model.util.Elements;

import javax.tools.Diagnostic;

/**

 * Annotation processor for the Deprecation Scanner tool.

 * Examines APIs for deprecated elements and records information

 *

 */

@SupportedAnnotationTypes("java.lang.Deprecated")

public class LoadProc extends AbstractProcessor {

    Elements elements;

    Messager messager;

    final List<DeprData> deprList = new ArrayList<>();

    public LoadProc() {

    }

    @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;

        }

        // Assume annotations contains only @Deprecated.

        // Note: no way to get deprecated packages, since

        // @Deprecated is ignored in package-info.java files.

        Set<? extends Element> set = roundEnv.getElementsAnnotatedWith(Deprecated.class);

        for (Element e : set) {

            ElementKind kind = e.getKind();

            Deprecated depr = e.getAnnotation(Deprecated.class);

            switch (kind) {

                case CLASS:

                case INTERFACE:

                case ENUM:

                case ANNOTATION_TYPE:

                    addType(kind, (TypeElement)e, depr);

                    break;

                case CONSTRUCTOR:

                case ENUM_CONSTANT:

                case FIELD:

                case METHOD:

                    Element encl = e.getEnclosingElement();

                    ElementKind enclKind = encl.getKind();

                    switch (enclKind) {

                        case CLASS:

                        case INTERFACE:

                        case ENUM:

                        case ANNOTATION_TYPE:

                            String detail = getDetail(e);

                            addMember(kind, (TypeElement)encl, detail, depr);

                            break;

                        default:

                            messager.printMessage(Diagnostic.Kind.WARNING,

                                "element " + e +

                                " within unknown enclosing element " + encl +

                                " of kind " + enclKind, e);

                            break;

                    }

                    break;

                default:

                    messager.printMessage(Diagnostic.Kind.WARNING,

                        "unknown element " + e +

                        " of kind " + kind +

                        " within " + e.getEnclosingElement(), e);

                    break;

            }

        }

        return true;

    }

    public List<DeprData> getDeprecations() {

        return deprList;

    }

    String getDetail(Element e) {

        if (e.getKind().isField()) {

            return e.getSimpleName().toString();

        } else {

            // method or constructor

            ExecutableElement ee = (ExecutableElement) e;

            String ret;

            ret = desc(ee.getReturnType());

            List<? extends TypeMirror> parameterTypes = ((ExecutableType)ee.asType()).getParameterTypes();

            String parms = parameterTypes.stream()

                                .map(this::desc)

                                .collect(Collectors.joining());

            return ee.getSimpleName().toString() + "(" + parms + ")" + ret;

        }

    }

    String desc(TypeMirror tm) {

        switch (tm.getKind()) {

            case BOOLEAN:

                return "Z";

            case BYTE:

                return "B";

            case SHORT:

                return "S";

            case CHAR:

                return "C";

            case INT:

                return "I";

            case LONG:

                return "J";

            case FLOAT:

                return "F";

            case DOUBLE:

                return "D";

            case VOID:

                return "V";

            case DECLARED:

                String s =

                    ((TypeElement)((DeclaredType)tm).asElement()).getQualifiedName().toString();

                s = s.replace('.', '/');

                return "L" + s + ";";

            case ARRAY:

                return "[" + desc(((ArrayType)tm).getComponentType());

            default:

                return tm.getKind().toString();

        }

    }

    void addType(ElementKind kind, TypeElement type, Deprecated dep) {

        addData(kind, type, "", dep);

    }

    void addMember(ElementKind kind, TypeElement type, String nameSig, Deprecated dep) {

        addData(kind, type, nameSig, dep);

    }

    void addData(ElementKind kind, TypeElement type, String nameSig, Deprecated dep) {

        String typeName = elements.getBinaryName(type).toString().replace('.', '/');

        String since = "";

        try {

            since = dep.since();

        } catch (IncompleteAnnotationException ignore) { }

        boolean forRemoval = false;

        try {

            forRemoval = dep.forRemoval();

        } catch (IncompleteAnnotationException ignore) { }

        deprList.add(new DeprData(kind, type, typeName, nameSig, since, forRemoval));

    }

}