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	/*
	* Copyright (c) 1996, 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 sun.net;

	/**
	* Helper class to map URL "abbreviations" to real URLs.
	* The default implementation supports the following mappings:
	* ftp.mumble.bar/... => ftp://ftp.mumble.bar/...
	* gopher.mumble.bar/... => gopher://gopher.mumble.bar/...
	* other.name.dom/... => http://other.name.dom/...
	* /foo/... => file:/foo/...
	*
	* Full URLs (those including a protocol name) are passed through unchanged.
	*
	* Subclassers can override or extend this behavior to support different
	* or additional canonicalization policies.
	*
	* @author Steve Byrne
	*/

	public class URLCanonicalizer {
	/**
	* Creates the default canonicalizer instance.
	*/
	public URLCanonicalizer() { }

	/**
	* Given a possibly abbreviated URL (missing a protocol name, typically),
	* this method's job is to transform that URL into a canonical form,
	* by including a protocol name and additional syntax, if necessary.
	*
	* For a correctly formed URL, this method should just return its argument.
	*/
	public String canonicalize(String simpleURL) {
	String resultURL = simpleURL;
	if (simpleURL.startsWith("ftp.")) {
	resultURL = "ftp://" + simpleURL;
	} else if (simpleURL.startsWith("gopher.")) {
	resultURL = "gopher://" + simpleURL;
	} else if (simpleURL.startsWith("/")) {
	resultURL = "file:" + simpleURL;
	} else if (!hasProtocolName(simpleURL)) {
	if (isSimpleHostName(simpleURL)) {
	simpleURL = "www." + simpleURL + ".com";
	}
	resultURL = "http://" + simpleURL;
	}

	return resultURL;
	}

	/**
	* Given a possibly abbreviated URL, this predicate function returns
	* true if it appears that the URL contains a protocol name
	*/
	public boolean hasProtocolName(String url) {
	int index = url.indexOf(':');
	if (index <= 0) { // treat ":foo" as not having a protocol spec
	return false;
	}

	for (int i = 0; i < index; i++) {
	char c = url.charAt(i);

	// REMIND: this is a guess at legal characters in a protocol --
	// need to be verified
	if ((c >= 'A' && c <= 'Z')
	\|\| (c >= 'a' && c <= 'z')
	\|\| (c == '-')) {
	continue;
	}

	// found an illegal character
	return false;
	}

	return true;
	}

	/**
	* Returns true if the URL is just a single name, no periods or
	* slashes, false otherwise
	**/
	protected boolean isSimpleHostName(String url) {

	for (int i = 0; i < url.length(); i++) {
	char c = url.charAt(i);

	// REMIND: this is a guess at legal characters in a protocol --
	// need to be verified
	if ((c >= 'A' && c <= 'Z')
	\|\| (c >= 'a' && c <= 'z')
	\|\| (c >= '0' && c <= '9')
	\|\| (c == '-')) {
	continue;
	}

	// found an illegal character
	return false;
	}

	return true;
	}
	}

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