//十进制转二进制
public void toBinary(int num)
{
StringBuffer buffer = new StringBuffer();
while(num > 0)
{
buffer.append(num % 2);
num = num / 2;
}
System.out.println(buffer.reverse());
}
//十进制转十六进制
public void toHex(int num)
{
StringBuffer buffer = new StringBuffer();
for(int x = 0; x < 8; x ++)//num转成二进制是八个四位一组的二进制
{
int temp = num & 15;//与15相&,获得低四位的二进制的十进制数
if(temp > 9)
{
//减10,比10大多少,加上A得到的是十六进制数 eg:14比10大4,'A'+4=69,在转成十六进制就是E
buffer.append((char)(temp -10 + 'A'));
}else{
buffer.append(temp);
}
num = num >>> 4;//无符号右移更新最低四位,防止负数右移后最高位加1
}
System.out.println(buffer.reverse());
}
通用进制转换
public void transform(int num, int base, int offser)
{
if(num == 0)
{
System.out.println(0);
return ;
}
char[] table = {'0','1','2','3','4','5','6','7','8','9','A','B','C','D','E','F'}
char[] arr = new char[32];
int pos = arr.length;
while(num != 0)
{
int temp = num & base;
arr[--pos] = table[temp];
num = num >>> offset;
}
for(int x = pos; x< arr.length; x ++)
{
System.out.println(arr[x]);
}
}
//二进制
public void toBinary(int num)
{
transform(num,1,1);
}
//八进制
public void toOctal(int num)
{
transform(num,7,3);
}
//十六进制
public void toHex(int num)
{
transform(num,15,4);
}