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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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 * published by the Free Software Foundation.  Oracle designates this
 * particular file as subject to the "Classpath" exception as provided
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 * 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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package jdk.javadoc.internal.doclets.toolkit.util;

import javax.lang.model.element.ModuleElement;
import javax.lang.model.element.PackageElement;
import javax.lang.model.element.TypeElement;

Abstraction for immutable relative paths.
Paths always use '/' as a separator, and never begin or end with '/'.
 
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.
/**
 * Abstraction for immutable relative paths.
 * Paths always use '/' as a separator, and never begin or end with '/'.
 *
 *  <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 DocPath {
    private final String path;

    
The empty path. /** The empty path. */
    public static final DocPath empty = new DocPath("");

    
The empty path. /** The empty path. */
    public static final DocPath parent = new DocPath("..");

    
Create a path from a string.
/**
     * Create a path from a string.
     */
    public static DocPath create(String p) {
        return (p == null) || p.isEmpty() ? empty : new DocPath(p);
    }

    
Return the path for a class.
For example, if the class is java.lang.Object,
the path is java/lang/Object.html.
/**
     * Return the path for a class.
     * For example, if the class is java.lang.Object,
     * the path is java/lang/Object.html.
     */
    public static DocPath forClass(Utils utils, TypeElement typeElement) {
        return (typeElement == null)
                ? empty
                : forPackage(utils.containingPackage(typeElement)).resolve(forName(utils, typeElement));
    }

    
Return the path for the simple name of the class.
For example, if the class is java.lang.Object,
the path is Object.html.
/**
     * Return the path for the simple name of the class.
     * For example, if the class is java.lang.Object,
     * the path is Object.html.
     */
    public static DocPath forName(Utils utils, TypeElement typeElement) {
        return (typeElement == null) ? empty : new DocPath(utils.getSimpleName(typeElement) + ".html");
    }

    public static DocPath forModule(ModuleElement mdle) {
        return mdle == null || mdle.isUnnamed()
                ? empty
                : DocPath.create(mdle.getQualifiedName().toString());
    }

    
Return the path for the package of a class.
For example, if the class is java.lang.Object,
the path is java/lang.
/**
     * Return the path for the package of a class.
     * For example, if the class is java.lang.Object,
     * the path is java/lang.
     */
    public static DocPath forPackage(Utils utils, TypeElement typeElement) {
        return (typeElement == null) ? empty : forPackage(utils.containingPackage(typeElement));
    }

    
Return the path for a package.
For example, if the package is java.lang,
the path is java/lang.
/**
     * Return the path for a package.
     * For example, if the package is java.lang,
     * the path is java/lang.
     */
    public static DocPath forPackage(PackageElement pkgElement) {
        return pkgElement == null || pkgElement.isUnnamed()
                ? empty
                : DocPath.create(pkgElement.getQualifiedName().toString().replace('.', '/'));
    }

    
Return the inverse path for a package.
For example, if the package is java.lang,
the inverse path is ../...
/**
     * Return the inverse path for a package.
     * For example, if the package is java.lang,
     * the inverse path is ../...
     */
    public static DocPath forRoot(PackageElement pkgElement) {
        String name = (pkgElement == null || pkgElement.isUnnamed())
                ? ""
                : pkgElement.getQualifiedName().toString();
        return new DocPath(name.replace('.', '/').replaceAll("[^/]+", ".."));
    }

    
Return the relative path from one package to another.
/**
     * Return the relative path from one package to another.
     */
    public static DocPath relativePath(PackageElement from, PackageElement to) {
        return forRoot(from).resolve(forPackage(to));
    }

    protected DocPath(String p) {
        path = (p.endsWith("/") ? p.substring(0, p.length() - 1) : p);
    }

    
{@inheritDoc} /** {@inheritDoc} */
    @Override
    public boolean equals(Object other) {
        return (other instanceof DocPath) && path.equals(((DocPath)other).path);
    }

    
{@inheritDoc} /** {@inheritDoc} */
    @Override
    public int hashCode() {
        return path.hashCode();
    }

    public DocPath basename() {
        int sep = path.lastIndexOf("/");
        return (sep == -1) ? this : new DocPath(path.substring(sep + 1));
    }

    public DocPath parent() {
        int sep = path.lastIndexOf("/");
        return (sep == -1) ? empty : new DocPath(path.substring(0, sep));
    }

    
Return the path formed by appending the specified string to the current path.
/**
     * Return the path formed by appending the specified string to the current path.
     */
    public DocPath resolve(String p) {
        if (p == null || p.isEmpty())
            return this;
        if (path.isEmpty())
            return new DocPath(p);
        return new DocPath(path + "/" + p);
    }

    
Return the path by appending the specified path to the current path.
/**
     * Return the path by appending the specified path to the current path.
     */
    public DocPath resolve(DocPath p) {
        if (p == null || p.isEmpty())
            return this;
        if (path.isEmpty())
            return p;
        return new DocPath(path + "/" + p.getPath());
    }

    
Return the inverse path for this path.
For example, if the path is a/b/c, the inverse path is ../../..
/**
     * Return the inverse path for this path.
     * For example, if the path is a/b/c, the inverse path is ../../..
     */
    public DocPath invert() {
        return new DocPath(path.replaceAll("[^/]+", ".."));
    }

    
Return true if this path is empty.
/**
     * Return true if this path is empty.
     */
    public boolean isEmpty() {
        return path.isEmpty();
    }

    public DocLink fragment(String fragment) {
        return new DocLink(path, null, fragment);
    }

    public DocLink query(String query) {
        return new DocLink(path, query, null);
    }

    
Return this path as a string.
/**
     * Return this path as a string.
     */
    // This is provided instead of using toString() to help catch
    // unintended use of toString() in string concatenation sequences.
    public String getPath() {
        return path;
    }
}