Logback: the reliable, generic, fast and flexible logging framework.
Copyright (C) 1999-2015, QOS.ch. All rights reserved.
This program and the accompanying materials are dual-licensed under
either the terms of the Eclipse Public License v1.0 as published by
the Eclipse Foundation
  or (per the licensee's choosing)
under the terms of the GNU Lesser General Public License version 2.1
as published by the Free Software Foundation.
/**
 * Logback: the reliable, generic, fast and flexible logging framework.
 * Copyright (C) 1999-2015, QOS.ch. All rights reserved.
 *
 * This program and the accompanying materials are dual-licensed under
 * either the terms of the Eclipse Public License v1.0 as published by
 * the Eclipse Foundation
 *
 *   or (per the licensee's choosing)
 *
 * under the terms of the GNU Lesser General Public License version 2.1
 * as published by the Free Software Foundation.
 */
package ch.qos.logback.core.encoder;

import java.io.ByteArrayOutputStream;

public class ByteArrayUtil {

    // big-endian
    static void writeInt(byte[] byteArray, int offset, int i) {
        for (int j = 0; j < 4; j++) {
            int shift = 24 - j * 8;
            byteArray[offset + j] = (byte) (i >>> shift);
        }
    }

    static void writeInt(ByteArrayOutputStream baos, int i) {
        for (int j = 0; j < 4; j++) {
            int shift = 24 - j * 8;
            baos.write((byte) (i >>> shift));
        }
    }

    // big-endian
    static int readInt(byte[] byteArray, int offset) {
        int i = 0;
        for (int j = 0; j < 4; j++) {
            int shift = 24 - j * 8;
            i += (byteArray[offset + j] & 0xFF) << shift;
        }
        return i;
    }

    static public String toHexString(byte[] ba) {
        StringBuilder sbuf = new StringBuilder();
        for (byte b : ba) {
            String s = Integer.toHexString((int) (b & 0xff));
            if (s.length() == 1) {
                sbuf.append('0');
            }
            sbuf.append(s);
        }
        return sbuf.toString();
    }

    static public byte[] hexStringToByteArray(String s) {
        int len = s.length();
        byte[] ba = new byte[len / 2];

        for (int i = 0; i < ba.length; i++) {
            int j = i * 2;
            int t = Integer.parseInt(s.substring(j, j + 2), 16);
            byte b = (byte) (t & 0xFF);
            ba[i] = b;
        }
        return ba;
    }
}