alpine.common.util.ByteUtil Maven / Gradle / Ivy
/*
* This file is part of Alpine.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*
* SPDX-License-Identifier: Apache-2.0
* Copyright (c) Steve Springett. All Rights Reserved.
*/
package alpine.common.util;
import java.nio.ByteBuffer;
import java.nio.CharBuffer;
import java.nio.charset.Charset;
import java.util.Arrays;
/**
* A collection of functions that operate on bytes.
*
* @author Steve Springett
* @since 1.0.0
*/
public final class ByteUtil {
/**
* Private constructor
*/
private ByteUtil() { }
/**
* Converts a char array to a byte array without the use of Strings.
*
* http://stackoverflow.com/questions/5513144/converting-char-to-byte
*
* @param chars the characters to convert
* @return a byte array of the converted characters
* @since 1.0.0
*/
public static byte[] toBytes(char[] chars) {
final CharBuffer charBuffer = CharBuffer.wrap(chars);
final ByteBuffer byteBuffer = Charset.forName("UTF-8").encode(charBuffer);
final byte[] bytes = Arrays.copyOfRange(byteBuffer.array(), byteBuffer.position(), byteBuffer.limit());
Arrays.fill(charBuffer.array(), '\u0000'); // clear sensitive data
Arrays.fill(byteBuffer.array(), (byte) 0); // clear sensitive data
return bytes;
}
}