java如何获取byte的高四位和低四位

public static int getHeight4(byte data){//获取高四位
    int height;
    height = ((data & 0xf0) >> 4);
    return height;
}
public static int getLow4(byte data){//获取低四位
    int low;
    low = (data & 0x0f);
    return low;
}

//获取一个字节高5位
public static int getHigh5Bit(byte b){undefined
return b >> 3;
}
//获取一个字节低3位
public static int getLow3Bit(byte b){undefined
return b&0x07;
}