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@groovelab
Last active May 11, 2021 11:24
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Kotlinの各型とByte配列の相互変換
// [0x00, 0xff] -> "00ff"
fun ByteArray.toHexString(asReverse: Boolean = false): String =
map { String.format("%02x", it) }
.let { if (asReverse) it.asReversed() else it }
.joinToString("")
// 2byte (Little Endian)
fun ByteArray.toShort(): Short {
var result: Int = 0
for (i in 0 until count()) {
result = result or (get(i).toUByte().toInt() shl 8 * i)
}
return result.toShort()
}
// 4byte (Little Endian)
fun ByteArray.toInt(): Int {
var result: Int = 0
for (i in 0 until count()) {
result = result or (get(i).toUByte().toInt() shl 8 * i)
}
return result
}
// 8byte (Little Endian)
fun ByteArray.toLong(): Long {
var result: Long = 0
for (i in 0 until count()) {
result = result or (get(i).toUByte().toLong() shl 8 * i)
}
return result
}
// 4byte (Little Endian)
fun ByteArray.toFloat() = intBitsToFloat(toInt())
// 8byte (Little Endian)
fun ByteArray.toDouble() = longBitsToDouble(toLong())
// "00ff" -> [0x00, 0xff]
fun String.asByteArray(): ByteArray {
val hexString = if (length % 2 == 0) this else "0${this}"
return hexString.chunked(2).map { it.asByte() }.toByteArray()
}
// "00" -> [0x00]
fun String.asByte() = substring(0, 2).toShort(16).toByte()
// 2byte (Little Endian)
fun Short.toBytes(): ByteArray {
var l = this.toInt()
val result = ByteArray(2)
for (i in 0..1) {
result[i] = (l and 0xff).toByte()
l = l shr 8
}
return result
}
// 4byte (Little Endian)
fun Int.toBytes(): ByteArray {
var l = this
val result = ByteArray(4)
for (i in 0..3) {
result[i] = (l and 0xff).toByte()
l = l shr 8
}
return result
}
// 8byte (Little Endian)
fun Long.toBytes():ByteArray {
var l = this
val result = ByteArray(8)
for (i in 0..7) {
result[i] = (l and 0xFF).toByte()
l = l shr 8
}
return result
}
// 4byte (Little Endian)
fun Float.toBytes() = toRawBits().toBytes()
// 8byte (Little Endian)
fun Double.toBytes() = toRawBits().toBytes()
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