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Simple Java library for stream ciphers based encryption

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package com.github.isaichkindanila.crypt.lib.util;

/**
 * Utility class to handle primitive-to-bytes conversions.
 */
@SuppressWarnings("WeakerAccess")
public class ConversionUtils {
    private ConversionUtils() {
    }

    /**
     * Converts 4 bytes to integer using low-endian format.
     *
     * @param bytes array of bytes
     * @param pos   first index of 4 bytes to convert to integer
     * @return integer parsed from bytes using low-endian format
     */
    public static int bytesToInt(byte[] bytes, int pos) {
        return bytes[pos] & 0xff
                | ((bytes[pos + 1] & 0xff) << 8)
                | ((bytes[pos + 2] & 0xff) << 16)
                | ((bytes[pos + 3] & 0xff) << 24);
    }

    /**
     * Converts 8 bytes to long using low-endian format.
     *
     * @param bytes array of bytes
     * @param pos   first index of 8 bytes to convert to long
     * @return long parsed from bytes using low-endian format
     */
    public static long bytesToLong(byte[] bytes, int pos) {
        return (long) bytes[pos] & 0xff
                | ((long) (bytes[pos + 1] & 0xff) << 8)
                | ((long) (bytes[pos + 2] & 0xff) << 16)
                | ((long) (bytes[pos + 3] & 0xff) << 24)
                | ((long) (bytes[pos + 4] & 0xff) << 32)
                | ((long) (bytes[pos + 5] & 0xff) << 40)
                | ((long) (bytes[pos + 6] & 0xff) << 48)
                | ((long) (bytes[pos + 7] & 0xff) << 56);
    }

    /**
     * Converts integer to 4 bytes using low-endian format.
     *
     * @param x integer to convert to bytes
     * @return 4 bytes representing integer in low-endian format
     */
    public static byte[] intToBytes(int x) {
        return new byte[]{
                (byte) x,
                (byte) (x >> 8),
                (byte) (x >> 16),
                (byte) (x >> 24)
        };
    }

    /**
     * Converts long to 8 bytes using low-endian format.
     *
     * @param x long to convert to bytes
     * @return 8 bytes representing long in low-endian format
     */
    public static byte[] longToBytes(long x) {
        return new byte[]{
                (byte) x,
                (byte) (x >> 8),
                (byte) (x >> 16),
                (byte) (x >> 24),
                (byte) (x >> 32),
                (byte) (x >> 40),
                (byte) (x >> 48),
                (byte) (x >> 56),
        };
    }
}