byte[] 與short、float、double的相互轉換
阿新 • • 發佈:2018-12-12
public class ShortFloatDoubleToByte { /** * double To byte[] * @param d * @return */ public static byte[] double2Bytes(double d) { long value = Double.doubleToRawLongBits(d); byte[] byteRet = new byte[8]; for (int i = 0; i < 8; i++) { byteRet[i] = (byte) ((value >> 8 * i) & 0xff); } return byteRet; } /** * byte[] To double * @param arr * @return */ public static double bytes2Double(byte[] arr) { long value = 0; for (int i = 0; i < 8; i++) { value |= ((long) (arr[i] & 0xff)) << (8 * i); } return Double.longBitsToDouble(value); } //將一位元組資料轉換成二進位制8bit字串 public static String byteToBinaryStr(byte data){ String data5Str = new BigInteger(1,new byte[]{data}).toString(2); while(data5Str.length()!=8){ data5Str="0"+data5Str; } return data5Str; } //二進位制轉換成十進位制 public static int binaryToDecimal(String binarySource) { BigInteger bi = new BigInteger(binarySource, 2); //轉換為BigInteger型別 return Integer.parseInt(bi.toString()); //轉換成十進位制 } //有符號整數 public static int byteToDecimalism(byte[] bytes){ String hex = ByteConvertUtil.bytes2HexString(bytes); BigInteger bi = new BigInteger(hex, 16); return bi.intValue(); } public static byte[] float2byte(float f) { // 把float轉換為byte[] int fbit = Float.floatToIntBits(f); byte[] b = new byte[4]; for (int i = 0; i < 4; i++) { b[i] = (byte) (fbit >> (24 - i * 8)); } // 翻轉陣列 int len = b.length; // 建立一個與源陣列元素型別相同的陣列 byte[] dest = new byte[len]; // 為了防止修改源陣列,將源陣列拷貝一份副本 System.arraycopy(b, 0, dest, 0, len); byte temp; // 將順位第i個與倒數第i個交換 for (int i = 0; i < len / 2; ++i) { temp = dest[i]; dest[i] = dest[len - i - 1]; dest[len - i - 1] = temp; } return dest; } //這個函式將byte轉換成float public static float byte2float(byte[] b) { int l; l = b[0]; l &= 0xff; l |= ((long) b[1] << 8); l &= 0xffff; l |= ((long) b[2] << 16); l &= 0xffffff; l |= ((long) b[3] << 24); return Float.intBitsToFloat(l); } public static byte[] short2Byte(short x){ byte high = (byte) (0x00FF & (x>>8)); //定義第一個byte byte low = (byte) (0x00FF & x); //定義第二個byte byte[] bytes = new byte[2]; bytes[0] = high; bytes[1] = low; return bytes; } public static short byte2Short(byte[] buf) { short r = 0; for (int i = 0; i < buf.length; i++) { r <<= 8; r |= (buf[i] & 0x00ff); } return r; } }