Java基本类型与byte数组之间相互转换

拼搏现实的明天。 2022-09-17 11:28 313阅读 0赞

package com.my.wxf4j.utils;
    
    import java.nio.charset.Charset;
    
    public class ByteUtil
    {
        public static byte[] getBytes(short data)
        {
            byte[] bytes = new byte[2];
            bytes[0] = (byte) (data & 0xff);
            bytes[1] = (byte) ((data & 0xff00) >> 8);
            return bytes;
        }
    
        public static byte[] getBytes(char data)
        {
            byte[] bytes = new byte[2];
            bytes[0] = (byte) (data);
            bytes[1] = (byte) (data >> 8);
            return bytes;
        }
    
        public static byte[] getBytes(int data)
        {
            byte[] bytes = new byte[4];
            bytes[0] = (byte) (data & 0xff);
            bytes[1] = (byte) ((data & 0xff00) >> 8);
            bytes[2] = (byte) ((data & 0xff0000) >> 16);
            bytes[3] = (byte) ((data & 0xff000000) >> 24);
            return bytes;
        }
    
        public static byte[] getBytes(long data)
        {
            byte[] bytes = new byte[8];
            bytes[0] = (byte) (data & 0xff);
            bytes[1] = (byte) ((data >> 8) & 0xff);
            bytes[2] = (byte) ((data >> 16) & 0xff);
            bytes[3] = (byte) ((data >> 24) & 0xff);
            bytes[4] = (byte) ((data >> 32) & 0xff);
            bytes[5] = (byte) ((data >> 40) & 0xff);
            bytes[6] = (byte) ((data >> 48) & 0xff);
            bytes[7] = (byte) ((data >> 56) & 0xff);
            return bytes;
        }
    
        public static byte[] getBytes(float data)
        {
            int intBits = Float.floatToIntBits(data);
            return getBytes(intBits);
        }
    
        public static byte[] getBytes(double data)
        {
            long intBits = Double.doubleToLongBits(data);
            return getBytes(intBits);
        }
    
        public static byte[] getBytes(String data, String charsetName)
        {
            Charset charset = Charset.forName(charsetName);
            return data.getBytes(charset);
        }
    
        public static byte[] getBytes(String data)
        {
            return getBytes(data, "GBK");
        }
    
        
        public static short getShort(byte[] bytes)
        {
            return (short) ((0xff & bytes[0]) | (0xff00 & (bytes[1] << 8)));
        }
    
        public static char getChar(byte[] bytes)
        {
            return (char) ((0xff & bytes[0]) | (0xff00 & (bytes[1] << 8)));
        }
    
        public static int getInt(byte[] bytes)
        {
            return (0xff & bytes[0]) | (0xff00 & (bytes[1] << 8)) | (0xff0000 & (bytes[2] << 16)) | (0xff000000 & (bytes[3] << 24));
        }
       
        public static long getLong(byte[] bytes)
        {
            return(0xffL & (long)bytes[0]) | (0xff00L & ((long)bytes[1] << 8)) | (0xff0000L & ((long)bytes[2] << 16)) | (0xff000000L & ((long)bytes[3] << 24))
             | (0xff00000000L & ((long)bytes[4] << 32)) | (0xff0000000000L & ((long)bytes[5] << 40)) | (0xff000000000000L & ((long)bytes[6] << 48)) | (0xff00000000000000L & ((long)bytes[7] << 56));
        }
    
        public static float getFloat(byte[] bytes)
        {
            return Float.intBitsToFloat(getInt(bytes));
        }
    
        public static double getDouble(byte[] bytes)
        {
            long l = getLong(bytes);
            System.out.println(l);
            return Double.longBitsToDouble(l);
        }
    
        public static String getString(byte[] bytes, String charsetName)
        {
            return new String(bytes, Charset.forName(charsetName));
        }
    
        public static String getString(byte[] bytes)
        {
            return getString(bytes, "GBK");
        }
    
        
        public static void main(String[] args)
        {
            short s = 122;
            int i = 122;
            long l = 1222222;
    
            char c = 'a';
    
            float f = 122.22f;
            double d = 122.22;
    
            String string = "我是好孩子";
            System.out.println(s);
            System.out.println(i);
            System.out.println(l);
            System.out.println(c);
            System.out.println(f);
            System.out.println(d);
            System.out.println(string);
    
            System.out.println("**************");
    
            System.out.println(getShort(getBytes(s)));
            System.out.println(getInt(getBytes(i)));
            System.out.println(getLong(getBytes(l)));
            System.out.println(getChar(getBytes(c)));
            System.out.println(getFloat(getBytes(f)));
            System.out.println(getDouble(getBytes(d)));
            System.out.println(getString(getBytes(string)));
        }
    }