java通过移位转16进制

public class Main {
public static void main(String []args)
{
Main main = new Main();
System.out.println("main: "+main.Hex(j));
System.out.println("Sys: "+Integer.toHexString(j));
}
private String Hex(int i)
{
String string="";
String temp = Integer.toBinaryString(i);
int len = temp.length();
System.out.println(temp);
System.out.println(len);
while(len%4!=0)
{
temp="0"+temp;
len=temp.length();
}
while(len>0)
{
//System.out.println(len+" "+string);
int bit = 0;
if(temp.charAt(len-1)=='1')
{
bit+=1;
}
if(temp.charAt(len-2)=='1')
{
bit+=2;
}
if(temp.charAt(len-3)=='1')
{
bit+=4;
}
if(temp.charAt(len-4)=='1')
{
bit+=8;
}
switch (bit) {
case 10:
string='A'+string;
break;
case 11:
string='B'+string;
break;
case 12:
string='C'+string;
break;
case 13:
string='D'+string;
break;
case 14:
string='E'+string;
break;
case 15:
string='F'+string;
break;

default:
string=bit+string;
break;
}
len-=4;
}

return string;
}
}