Copyright (c) 2000, 2017 IBM Corporation and others.
This program and the accompanying materials
are made available under the terms of the Eclipse Public License 2.0
which accompanies this distribution, and is available at
https://www.eclipse.org/legal/epl-2.0/
SPDX-License-Identifier: EPL-2.0
Contributors:
    IBM Corporation - initial API and implementation
/*******************************************************************************
 * Copyright (c) 2000, 2017 IBM Corporation and others.
 *
 * This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License 2.0
 * which accompanies this distribution, and is available at
 * https://www.eclipse.org/legal/epl-2.0/
 *
 * SPDX-License-Identifier: EPL-2.0
 *
 * Contributors:
 *     IBM Corporation - initial API and implementation
 *******************************************************************************/
package org.eclipse.core.internal.utils;

import java.nio.charset.StandardCharsets;

public class Convert {

	
Converts the string argument to a byte array.
/**
	 * Converts the string argument to a byte array.
	 */
	public static String fromUTF8(byte[] b) {
		return new String(b, StandardCharsets.UTF_8);
	}

	
Converts the string argument to a byte array.
/**
	 * Converts the string argument to a byte array.
	 */
	public static byte[] toUTF8(String s) {
		return s.getBytes(StandardCharsets.UTF_8);
	}

	
Performs conversion of a long value to a byte array representation.
See Also:
bytesToLong(byte[])/**
	 * Performs conversion of a long value to a byte array representation.
	 *
	 * @see #bytesToLong(byte[])
	 */
	public static byte[] longToBytes(long value) {

		// A long value is 8 bytes in length.
		byte[] bytes = new byte[8];

		// Convert and copy value to byte array:
		//   -- Cast long to a byte to retrieve least significant byte;
		//   -- Left shift long value by 8 bits to isolate next byte to be converted;
		//   -- Repeat until all 8 bytes are converted (long = 64 bits).
		// Note: In the byte array, the least significant byte of the long is held in
		// the highest indexed array bucket.

		for (int i = 0; i < bytes.length; i++) {
			bytes[(bytes.length - 1) - i] = (byte) value;
			value >>>= 8;
		}

		return bytes;
	}

	
Performs conversion of a byte array to a long representation.
See Also:
longToBytes(long)/**
	 * Performs conversion of a byte array to a long representation.
	 *
	 * @see #longToBytes(long)
	 */
	public static long bytesToLong(byte[] value) {

		long longValue = 0L;

		// See method convertLongToBytes(long) for algorithm details.
		for (byte element : value) {
			// Left shift has no effect thru first iteration of loop.
			longValue <<= 8;
			longValue ^= element & 0xFF;
		}

		return longValue;
	}
}