//java.lang.Integer类     
parseInt(String s, int radix)    
   
//使用第二个参数指定的基数，将字符串参数解析为有符号的整数。    
   
examples from jdk:    
   
parseInt("0", 10) returns 0    
   
parseInt("473", 10) returns 473    
   
parseInt("-0", 10) returns 0    
   
parseInt("-FF", 16) returns -255    
   
parseInt("1100110", 2) returns 102    
   
parseInt("2147483647", 10) returns 2147483647    
   
parseInt("-2147483648", 10) returns -2147483648    
   
parseInt("2147483648", 10) throws a NumberFormatException    
   
parseInt("99",throws a NumberFormatException    
   
parseInt("Kona", 10) throws a NumberFormatException    
   
parseInt("Kona", 27) returns 411787    

Integer.toBinaryString    
   
Integer.toOctalString    
   
Integer.toHexString    

public class Test{    
   
public static void main(String args[]){    
   
   
   
int i=100;    
   
String binStr=Integer.toBinaryString(i);    
   
String otcStr=Integer.toOctalString(i);    
   
String hexStr=Integer.toHexString(i);    
   
System.out.println(binStr);    
   
   
   
}    

public class TestStringFormat {    
   
public static void main(String[] args) {    
   
if (args.length == 0) {    
   
System.out.println("usage: java TestStringFormat <a number>");    
   
System.exit(0);    
   
}    
   
   
   
Integer factor = Integer.valueOf(args[0]);    
   
   
   
String s;    
   
   
   
s = String.format("%d", factor);    
   
System.out.println(s);    
   
s = String.format("%x", factor);    
   
System.out.println(s);    
   
s = String.format("%o", factor);    
   
System.out.println(s);    
   
}    
   
}    

     Integer.toHexString(你的10进制数);    

String temp = Integer.toHexString(75);    

   
//输入一个10进制数字并把它转换成16进制    
   
import java.io.*;    
   
public class toHex{    
   
   
   
public static void main(String[]args){    
   
   
   
int input;//存放输入数据    
   
//创建输入字符串的实例    
   
BufferedReader strin=new BufferedReader(new InputStreamReader(System.in));    
   
System.out.println("请输入一个的整数：");    
   
String x=null;    
   
try{    
   
x=strin.readLine();    
   
}catch(IOException ex){    
   
ex.printStackTrace();    
   
}    
   
input=Integer.parseInt(x);    
   
System.out.println ("你输入的数字是："+input);//输出从键盘接收到的数字    
   
   
   
System.out.println ("它的16进制是："+Integer.toHexString(input));//用toHexString把10进制转换成16进制    
   
}    
   
}