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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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 * This code is free software; you can redistribute it and/or modify it
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 * 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.
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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).
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 * 2 along with this work; if not, write to the Free Software Foundation,
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package jdk.javadoc.internal.doclets.formats.html;

import java.util.ArrayList;
import java.util.EnumSet;
import java.util.List;
import java.util.Set;

import javax.lang.model.element.AnnotationMirror;
import javax.lang.model.element.Element;
import javax.lang.model.element.TypeElement;
import javax.lang.model.type.DeclaredType;
import javax.lang.model.type.TypeMirror;

import jdk.javadoc.internal.doclets.formats.html.markup.ContentBuilder;
import jdk.javadoc.internal.doclets.formats.html.markup.Entity;
import jdk.javadoc.internal.doclets.formats.html.markup.HtmlTree;
import jdk.javadoc.internal.doclets.toolkit.BaseConfiguration;
import jdk.javadoc.internal.doclets.toolkit.Content;
import jdk.javadoc.internal.doclets.toolkit.Resources;
import jdk.javadoc.internal.doclets.toolkit.util.DocPath;
import jdk.javadoc.internal.doclets.toolkit.util.DocPaths;
import jdk.javadoc.internal.doclets.toolkit.util.DocletConstants;
import jdk.javadoc.internal.doclets.toolkit.util.Utils.ElementFlag;
import jdk.javadoc.internal.doclets.toolkit.util.links.LinkFactory;
import jdk.javadoc.internal.doclets.toolkit.util.links.LinkInfo;

A factory that returns a link given the information about it.
 
This is NOT part of any supported API.
 If you write code that depends on this, you do so at your own risk.
 This code and its internal interfaces are subject to change or
 deletion without notice.
/**
 * A factory that returns a link given the information about it.
 *
 *  <p><b>This is NOT part of any supported API.
 *  If you write code that depends on this, you do so at your own risk.
 *  This code and its internal interfaces are subject to change or
 *  deletion without notice.</b>
 */
public class HtmlLinkFactory extends LinkFactory {

    private final HtmlDocletWriter m_writer;
    private final DocPaths docPaths;

    public HtmlLinkFactory(HtmlDocletWriter writer) {
        super(writer.configuration.utils);
        m_writer = writer;
        docPaths = writer.configuration.docPaths;
    }

    @Override
    protected Content newContent() {
        return new ContentBuilder();
    }

    @Override
    protected Content getClassLink(LinkInfo linkInfo) {
        BaseConfiguration configuration = m_writer.configuration;
        HtmlLinkInfo classLinkInfo = (HtmlLinkInfo) linkInfo;
        TypeElement typeElement = classLinkInfo.typeElement;
        // Create a tool tip if we are linking to a class or interface.  Don't
        // create one if we are linking to a member.
        String title = "";
        boolean hasWhere = classLinkInfo.where != null && classLinkInfo.where.length() != 0;
        if (!hasWhere) {
            boolean isTypeLink = classLinkInfo.type != null &&
                     utils.isTypeVariable(utils.getComponentType(classLinkInfo.type));
            title = getClassToolTip(typeElement, isTypeLink);
        }
        Content label = classLinkInfo.getClassLinkLabel(configuration);
        Set<ElementFlag> flags;
        Element target;
        boolean showPreview = !classLinkInfo.skipPreview;
        if (!hasWhere && showPreview) {
            flags = utils.elementFlags(typeElement);
            target = typeElement;
        } else if ((classLinkInfo.context == HtmlLinkInfo.Kind.SEE_TAG || classLinkInfo.context == HtmlLinkInfo.Kind.MEMBER_DEPRECATED_PREVIEW) &&
                   classLinkInfo.targetMember != null && showPreview) {
            flags = utils.elementFlags(classLinkInfo.targetMember);
            target = classLinkInfo.targetMember;
        } else {
            flags = EnumSet.noneOf(ElementFlag.class);
            target = null;
        }

        Content link = new ContentBuilder();
        if (utils.isIncluded(typeElement)) {
            if (configuration.isGeneratedDoc(typeElement) && !utils.hasHiddenTag(typeElement)) {
                DocPath filename = getPath(classLinkInfo);
                if (linkInfo.linkToSelf ||
                                !(docPaths.forName(typeElement)).equals(m_writer.filename)) {
                        link.add(m_writer.links.createLink(
                                filename.fragment(classLinkInfo.where),
                                label,
                                classLinkInfo.style,
                                title));
                        if (flags.contains(ElementFlag.PREVIEW)) {
                            link.add(HtmlTree.SUP(m_writer.links.createLink(
                                    filename.fragment(m_writer.htmlIds.forPreviewSection(target).name()),
                                    m_writer.contents.previewMark)));
                        }
                        return link;
                }
            }
        } else {
            Content crossLink = m_writer.getCrossClassLink(
                typeElement, classLinkInfo.where,
                label, classLinkInfo.style, true);
            if (crossLink != null) {
                link.add(crossLink);
                if (flags.contains(ElementFlag.PREVIEW)) {
                    link.add(HtmlTree.SUP(m_writer.getCrossClassLink(
                        typeElement,
                        m_writer.htmlIds.forPreviewSection(target).name(),
                        m_writer.contents.previewMark,
                        null, false)));
                }
                return link;
            }
        }
        // Can't link so just write label.
        link.add(label);
        if (flags.contains(ElementFlag.PREVIEW)) {
            link.add(HtmlTree.SUP(m_writer.contents.previewMark));
        }
        return link;
    }

    @Override
    protected Content getTypeParameterLinks(LinkInfo linkInfo) {
        Content links = newContent();
        List<TypeMirror> vars = new ArrayList<>();
        TypeMirror ctype = linkInfo.type != null
                ? utils.getComponentType(linkInfo.type)
                : null;
        if (linkInfo.executableElement != null) {
            linkInfo.executableElement.getTypeParameters().forEach(t -> vars.add(t.asType()));
        } else if (linkInfo.type != null && utils.isDeclaredType(linkInfo.type)) {
            vars.addAll(((DeclaredType) linkInfo.type).getTypeArguments());
        } else if (ctype != null && utils.isDeclaredType(ctype)) {
            vars.addAll(((DeclaredType) ctype).getTypeArguments());
        } else if (ctype == null && linkInfo.typeElement != null) {
            linkInfo.typeElement.getTypeParameters().forEach(t -> vars.add(t.asType()));
        } else {
            // Nothing to document.
            return links;
        }
        if (!vars.isEmpty()) {
            links.add("<");
            boolean many = false;
            for (TypeMirror t : vars) {
                if (many) {
                    links.add(",");
                    links.add(Entity.ZERO_WIDTH_SPACE);
                    if (((HtmlLinkInfo) linkInfo).getContext() == HtmlLinkInfo.Kind.MEMBER_TYPE_PARAMS) {
                        links.add(DocletConstants.NL);
                    }
                }
                links.add(getTypeParameterLink(linkInfo, t));
                many = true;
            }
            links.add(">");
        }
        return links;
    }

    
Returns a link to the given type parameter.
Params:
linkInfo –     the information about the link to construct
typeParam – the type parameter to link to
Returns:
the link/**
     * Returns a link to the given type parameter.
     *
     * @param linkInfo     the information about the link to construct
     * @param typeParam the type parameter to link to
     * @return the link
     */
    protected Content getTypeParameterLink(LinkInfo linkInfo, TypeMirror typeParam) {
        HtmlLinkInfo typeLinkInfo = new HtmlLinkInfo(m_writer.configuration,
                ((HtmlLinkInfo) linkInfo).getContext(), typeParam).skipPreview(true);
        typeLinkInfo.excludeTypeBounds = linkInfo.excludeTypeBounds;
        typeLinkInfo.excludeTypeParameterLinks = linkInfo.excludeTypeParameterLinks;
        typeLinkInfo.linkToSelf = linkInfo.linkToSelf;
        return getLink(typeLinkInfo);
    }

    @Override
    public Content getTypeAnnotationLinks(LinkInfo linkInfo) {
        ContentBuilder links = new ContentBuilder();
        List<? extends AnnotationMirror> annotations;
        if (utils.isAnnotated(linkInfo.type)) {
            annotations = linkInfo.type.getAnnotationMirrors();
        } else if (utils.isTypeVariable(linkInfo.type)) {
            // TODO: use the context for now, and special case for Receiver_Types,
            // which takes the default case.
            switch (((HtmlLinkInfo)linkInfo).context) {
                case MEMBER_TYPE_PARAMS:
                case EXECUTABLE_MEMBER_PARAM:
                case CLASS_SIGNATURE:
                    Element element = utils.typeUtils.asElement(linkInfo.type);
                    annotations = element.getAnnotationMirrors();
                    break;
                default:
                    annotations = linkInfo.type.getAnnotationMirrors();
                    break;
            }

        } else {
            return links;
        }

        if (annotations.isEmpty())
            return links;

        m_writer.getAnnotations(annotations, false)
                .forEach(a -> {
                    links.add(a);
                    links.add(" ");
                });

        return links;
    }

    
Given a class, return the appropriate tool tip.
Params:
typeElement – the class to get the tool tip for.
Returns:
the tool tip for the appropriate class./**
     * Given a class, return the appropriate tool tip.
     *
     * @param typeElement the class to get the tool tip for.
     * @return the tool tip for the appropriate class.
     */
    private String getClassToolTip(TypeElement typeElement, boolean isTypeLink) {
        Resources resources = m_writer.configuration.getDocResources();
        if (isTypeLink) {
            return resources.getText("doclet.Href_Type_Param_Title",
                    utils.getSimpleName(typeElement));
        } else if (utils.isInterface(typeElement)){
            return resources.getText("doclet.Href_Interface_Title",
                m_writer.getLocalizedPackageName(utils.containingPackage(typeElement)));
        } else if (utils.isAnnotationType(typeElement)) {
            return resources.getText("doclet.Href_Annotation_Title",
                m_writer.getLocalizedPackageName(utils.containingPackage(typeElement)));
        } else if (utils.isEnum(typeElement)) {
            return resources.getText("doclet.Href_Enum_Title",
                m_writer.getLocalizedPackageName(utils.containingPackage(typeElement)));
        } else {
            return resources.getText("doclet.Href_Class_Title",
                m_writer.getLocalizedPackageName(utils.containingPackage(typeElement)));
        }
    }

    
Return path to the given file name in the given package. So if the name
passed is "Object.html" and the name of the package is "java.lang", and
if the relative path is "../.." then returned string will be
"../../java/lang/Object.html"
Params:
linkInfo – the information about the link./**
     * Return path to the given file name in the given package. So if the name
     * passed is "Object.html" and the name of the package is "java.lang", and
     * if the relative path is "../.." then returned string will be
     * "../../java/lang/Object.html"
     *
     * @param linkInfo the information about the link.
     */
    private DocPath getPath(HtmlLinkInfo linkInfo) {
        return m_writer.pathToRoot.resolve(docPaths.forClass(linkInfo.typeElement));
    }
}