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	/*
	* Copyright (c) 1998, 2019, 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 javax.crypto.spec;

	import java.security.spec.AlgorithmParameterSpec;

	/**
	* This class specifies the parameters used with the
	* <a href="http://www.ietf.org/rfc/rfc2040.txt"><i>RC5</i></a>
	* algorithm.
	*
	* <p> The parameters consist of a version number, a rounds count, a word
	* size, and optionally an initialization vector (IV) (only in feedback mode).
	*
	* <p> This class can be used to initialize a {@code Cipher} object that
	* implements the <i>RC5</i> algorithm as supplied by
	* <a href="http://www.rsasecurity.com">RSA Security Inc.</a>,
	* or any parties authorized by RSA Security.
	*
	* @author Jan Luehe
	*
	* @since 1.4
	*/
	public class RC5ParameterSpec implements AlgorithmParameterSpec {

	private byte[] iv = null;
	private int version;
	private int rounds;
	private int wordSize; // the word size in bits

	/**
	* Constructs a parameter set for RC5 from the given version, number of
	* rounds and word size (in bits).
	*
	* @param version the version.
	* @param rounds the number of rounds.
	* @param wordSize the word size in bits.
	*/
	public RC5ParameterSpec(int version, int rounds, int wordSize) {
	this.version = version;
	this.rounds = rounds;
	this.wordSize = wordSize;
	}

	/**
	* Constructs a parameter set for RC5 from the given version, number of
	* rounds, word size (in bits), and IV.
	*
	* <p> Note that the size of the IV (block size) must be twice the word
	* size. The bytes that constitute the IV are those between
	* {@code iv[0]} and {@code iv[2*(wordSize/8)-1]} inclusive.
	*
	* @param version the version.
	* @param rounds the number of rounds.
	* @param wordSize the word size in bits.
	* @param iv the buffer with the IV. The first {@code 2*(wordSize/8)
	* } bytes of the buffer are copied to protect against subsequent
	* modification.
	* @exception IllegalArgumentException if {@code iv} is
	* {@code null} or {@code (iv.length < 2 * (wordSize / 8))}
	*/
	public RC5ParameterSpec(int version, int rounds, int wordSize, byte[] iv) {
	this(version, rounds, wordSize, iv, 0);
	}

	/**
	* Constructs a parameter set for RC5 from the given version, number of
	* rounds, word size (in bits), and IV.
	*
	* <p> The IV is taken from {@code iv}, starting at
	* {@code offset} inclusive.
	* Note that the size of the IV (block size), starting at
	* {@code offset} inclusive, must be twice the word size.
	* The bytes that constitute the IV are those between
	* {@code iv[offset]} and {@code iv[offset+2*(wordSize/8)-1]}
	* inclusive.
	*
	* @param version the version.
	* @param rounds the number of rounds.
	* @param wordSize the word size in bits.
	* @param iv the buffer with the IV. The first {@code 2*(wordSize/8)
	* } bytes of the buffer beginning at {@code offset}
	* inclusive are copied to protect against subsequent modification.
	* @param offset the offset in {@code iv} where the IV starts.
	* @exception IllegalArgumentException if {@code iv} is
	* {@code null} or
	* {@code (iv.length - offset < 2 * (wordSize / 8))}
	*/
	public RC5ParameterSpec(int version, int rounds, int wordSize,
	byte[] iv, int offset) {
	this.version = version;
	this.rounds = rounds;
	this.wordSize = wordSize;
	if (iv == null) throw new IllegalArgumentException("IV missing");
	int blockSize = (wordSize / 8) * 2;
	if (iv.length - offset < blockSize) {
	throw new IllegalArgumentException("IV too short");
	}
	this.iv = new byte[blockSize];
	System.arraycopy(iv, offset, this.iv, 0, blockSize);
	}

	/**
	* Returns the version.
	*
	* @return the version.
	*/
	public int getVersion() {
	return this.version;
	}

	/**
	* Returns the number of rounds.
	*
	* @return the number of rounds.
	*/
	public int getRounds() {
	return this.rounds;
	}

	/**
	* Returns the word size in bits.
	*
	* @return the word size in bits.
	*/
	public int getWordSize() {
	return this.wordSize;
	}

	/**
	* Returns the IV or null if this parameter set does not contain an IV.
	*
	* @return the IV or null if this parameter set does not contain an IV.
	* Returns a new array each time this method is called.
	*/
	public byte[] getIV() {
	return (iv == null? null:iv.clone());
	}

	/**
	* Tests for equality between the specified object and this
	* object. Two RC5ParameterSpec objects are considered equal if their
	* version numbers, number of rounds, word sizes, and IVs are equal.
	* (Two IV references are considered equal if both are {@code null}.)
	*
	* @param obj the object to test for equality with this object.
	*
	* @return true if the objects are considered equal, false if
	* {@code obj} is null or otherwise.
	*/
	public boolean equals(Object obj) {
	if (obj == this) {
	return true;
	}
	if (!(obj instanceof RC5ParameterSpec)) {
	return false;
	}
	RC5ParameterSpec other = (RC5ParameterSpec) obj;

	return ((version == other.version) &&
	(rounds == other.rounds) &&
	(wordSize == other.wordSize) &&
	java.util.Arrays.equals(iv, other.iv));
	}

	/**
	* Calculates a hash code value for the object.
	* Objects that are equal will also have the same hashcode.
	*/
	public int hashCode() {
	int retval = 0;
	if (iv != null) {
	for (int i = 1; i < iv.length; i++) {
	retval += iv[i] * i;
	}
	}
	retval += (version + rounds + wordSize);
	return retval;
	}
	}

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