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	/*
	* Copyright (c) 2005, 2021, 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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	/*
	*******************************************************************************
	* (C) Copyright IBM Corp. 1996-2005 - All Rights Reserved *
	* *
	* The original version of this source code and documentation is copyrighted *
	* and owned by IBM, These materials are provided under terms of a License *
	* Agreement between IBM and Sun. This technology is protected by multiple *
	* US and International patents. This notice and attribution to IBM may not *
	* to removed. *
	*******************************************************************************
	*/

	package java.text;

	import jdk.internal.icu.text.NormalizerBase;

	/**
	* This class provides the method {@code normalize} which transforms Unicode
	* text into an equivalent composed or decomposed form, allowing for easier
	* sorting and searching of text.
	* The {@code normalize} method supports the standard normalization forms
	* described in
	* <a href="https://www.unicode.org/reports/tr15/">
	* Unicode Standard Annex #15 — Unicode Normalization Forms</a>.
	* <p>
	* Characters with accents or other adornments can be encoded in
	* several different ways in Unicode. For example, take the character A-acute.
	* In Unicode, this can be encoded as a single character (the "composed" form):
	*
	* <pre>
	* U+00C1 LATIN CAPITAL LETTER A WITH ACUTE</pre>
	*
	* or as two separate characters (the "decomposed" form):
	*
	* <pre>
	* U+0041 LATIN CAPITAL LETTER A
	* U+0301 COMBINING ACUTE ACCENT</pre>
	*
	* To a user of your program, however, both of these sequences should be
	* treated as the same "user-level" character "A with acute accent". When you
	* are searching or comparing text, you must ensure that these two sequences are
	* treated as equivalent. In addition, you must handle characters with more than
	* one accent. Sometimes the order of a character's combining accents is
	* significant, while in other cases accent sequences in different orders are
	* really equivalent.
	* <p>
	* Similarly, the string "ffi" can be encoded as three separate letters:
	*
	* <pre>
	* U+0066 LATIN SMALL LETTER F
	* U+0066 LATIN SMALL LETTER F
	* U+0069 LATIN SMALL LETTER I</pre>
	*
	* or as the single character
	*
	* <pre>
	* U+FB03 LATIN SMALL LIGATURE FFI</pre>
	*
	* The ffi ligature is not a distinct semantic character, and strictly speaking
	* it shouldn't be in Unicode at all, but it was included for compatibility
	* with existing character sets that already provided it. The Unicode standard
	* identifies such characters by giving them "compatibility" decompositions
	* into the corresponding semantic characters. When sorting and searching, you
	* will often want to use these mappings.
	* <p>
	* The {@code normalize} method helps solve these problems by transforming
	* text into the canonical composed and decomposed forms as shown in the first
	* example above. In addition, you can have it perform compatibility
	* decompositions so that you can treat compatibility characters the same as
	* their equivalents.
	* Finally, the {@code normalize} method rearranges accents into the
	* proper canonical order, so that you do not have to worry about accent
	* rearrangement on your own.
	* <p>
	* The W3C generally recommends to exchange texts in NFC.
	* Note also that most legacy character encodings use only precomposed forms and
	* often do not encode any combining marks by themselves. For conversion to such
	* character encodings the Unicode text needs to be normalized to NFC.
	* For more usage examples, see the Unicode Standard Annex.
	*
	* @since 1.6
	*/
	public final class Normalizer {

	private Normalizer() {};

	/**
	* This enum provides constants of the four Unicode normalization forms
	* that are described in
	* <a href="https://www.unicode.org/reports/tr15/">
	* Unicode Standard Annex #15 — Unicode Normalization Forms</a>
	* and two methods to access them.
	*
	* @since 1.6
	*/
	public static enum Form {

	/**
	* Canonical decomposition.
	*/
	NFD,

	/**
	* Canonical decomposition, followed by canonical composition.
	*/
	NFC,

	/**
	* Compatibility decomposition.
	*/
	NFKD,

	/**
	* Compatibility decomposition, followed by canonical composition.
	*/
	NFKC
	}

	/**
	* Normalize a sequence of char values.
	* The sequence will be normalized according to the specified normalization
	* form.
	* @param src The sequence of char values to normalize.
	* @param form The normalization form; one of
	* {@link java.text.Normalizer.Form#NFC},
	* {@link java.text.Normalizer.Form#NFD},
	* {@link java.text.Normalizer.Form#NFKC},
	* {@link java.text.Normalizer.Form#NFKD}
	* @return The normalized String
	* @throws NullPointerException If {@code src} or {@code form}
	* is null.
	*/
	public static String normalize(CharSequence src, Form form) {
	return NormalizerBase.normalize(src.toString(), form);
	}

	/**
	* Determines if the given sequence of char values is normalized.
	* @param src The sequence of char values to be checked.
	* @param form The normalization form; one of
	* {@link java.text.Normalizer.Form#NFC},
	* {@link java.text.Normalizer.Form#NFD},
	* {@link java.text.Normalizer.Form#NFKC},
	* {@link java.text.Normalizer.Form#NFKD}
	* @return true if the sequence of char values is normalized;
	* false otherwise.
	* @throws NullPointerException If {@code src} or {@code form}
	* is null.
	*/
	public static boolean isNormalized(CharSequence src, Form form) {
	return NormalizerBase.isNormalized(src.toString(), form);
	}
	}

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