jdk.javadoc.internal.doclets.toolkit.util.DocLink Maven / Gradle / Ivy
/*
* Copyright (c) 2012, 2020, 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
* or visit www.oracle.com if you need additional information or have any
* questions.
*/
package jdk.javadoc.internal.doclets.toolkit.util;
/**
* Abstraction for simple relative URIs, consisting of a path and an
* optional fragment. DocLink objects can be created by the constructors
* below or from a DocPath using the convenience
* {@link DocPath#fragment fragment} method.
*
* 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.
*
*/
public class DocLink {
final DocPath path;
final String fragment;
/**
* Creates a DocLink representing the URI {@code #fragment}.
* @param fragment the fragment
* @return the DocLink
*/
public static DocLink fragment(String fragment) {
return new DocLink((DocPath) null, fragment);
}
/**
* Creates a DocLink representing the URI {@code path}.
* @param path the path
*/
public DocLink(DocPath path) {
this(path, null);
}
/**
* Creates a DocLink representing the URI {@code path#fragment}.
* Any of the component parts may be null.
* @param path the path
* @param fragment the fragment
*/
public DocLink(DocPath path, String fragment) {
this.path = path;
this.fragment = fragment;
}
/**
* Creates a DocLink representing the URI {@code path#fragment}.
* Any of the component parts may be null.
* @param path the path
* @param fragment the fragment
*/
public DocLink(String path, String fragment) {
this(DocPath.create(path), fragment);
}
/**
* Creates a DocLink formed by relativizing the path against a given base.
* @param base the base
* @return the DocLink
*/
public DocLink relativizeAgainst(DocPath base) {
if (base.isEmpty() || path == null) {
return this;
}
// The following guards against the (ugly) use-case of using DocPath to contain a URL
if (isAbsoluteURL(path)) {
return this;
}
DocPath newPath = base.relativize(path);
// avoid generating an empty link by using the basename of the path if necessary
if (newPath.isEmpty() && isEmpty(fragment)) {
newPath = path.basename();
}
return new DocLink(newPath, fragment);
}
// return true if the path begins ://
private boolean isAbsoluteURL(DocPath path) {
String s = path.getPath();
for (int i = 0; i < s.length(); i++) {
char c = s.charAt(i);
if (Character.isLetter(c)) {
continue;
}
return (c == ':' && i + 2 < s.length() && s.charAt(i + 1)== '/' && s.charAt(i + 2)== '/');
}
return false;
}
/**
* Returns the link in the form "path#fragment", omitting any empty
* components.
* @return the string
*/
@Override
public String toString() {
// common fast path
if (path != null && isEmpty(fragment))
return path.getPath();
StringBuilder sb = new StringBuilder();
if (path != null)
sb.append(path.getPath());
if (!isEmpty(fragment))
sb.append("#").append(fragment);
return sb.toString();
}
private static boolean isEmpty(String s) {
return (s == null) || s.isEmpty();
}
}