java byte 的各种转换

谁借莪１个温暖的怀抱￠ 2024-04-17 06:37 42阅读 0赞

// byte[]与int转换
    public static int byteArrayToInt(byte[] b) {   
    return   b[3] & 0xFF |   
    
                (b[2] & 0xFF) << 8 |   
    
                (b[1] & 0xFF) << 16 |   
    
                (b[0] & 0xFF) << 24;   
    
    }   
    
    public static byte[] intToByteArray(int a) {   
    return new byte[] {   
    
            (byte) ((a >> 24) & 0xFF),   
    
            (byte) ((a >> 16) & 0xFF),      
    
            (byte) ((a >> 8) & 0xFF),      
    
            (byte) (a & 0xFF)   
    
        };   
    }
    
    // byte[]与long转换
    public static byte[] long2byte(long res) {
            byte[] buffer = new byte[8];
            for (int i = 0; i < 8; i++) {
                int offset = 64 - (i + 1) * 8;
                buffer[i] = (byte) ((res >> offset) & 0xff);
            }
            return buffer;
        }
    
        public static long byteArrayToLong(byte[] b){
            long values = 0;
            for (int i = 0; i < 8; i++) {
                values <<= 8; values|= (b[i] & 0xff);
            }
            return values;
        }
    
    public static void transform(bytes[] bytes) {  
            System.out.println("2进制："   + binary(bytes, 2));  
            System.out.println("5进制："   + binary(bytes, 5));  
            System.out.println("8进制："   + binary(bytes, 8));  
            System.out.println("16进制："  + binary(bytes, 16));  
            System.out.println("32进制："  + binary(bytes, 32));  
            System.out.println("64进制："  + binary(bytes, 64));// 这个已经超出范围，超出范围后变为10进制显示  
        } 
    
    /**
         * 将byte[]转为各种进制的字符串
         * @param bytes byte[]
         * @param radix 基数可以转换进制的范围，从Character.MIN_RADIX到Character.MAX_RADIX，超出范围后变为10进制
         * @return 转换后的字符串
         */
        public static String binary(byte[] bytes, int radix){
            return new BigInteger(1, bytes).toString(radix);// 这里的1代表正数
        }