用Java实现十六进制转十进制

import java.util.*;

public class Transfer {
public static  void main(String[]args){
Scanner input=new Scanner(System.in);

String hex=input.nextLine();
System.out.println("hex:"+hex.toUpperCase());
System.out.println("Decimal:"+hexToDecimal(hex.toUpperCase()));
// char c='0';
// System.out.println(hexCharToDecimal(c));
}

public static int hexToDecimal(String hex)
{
int decimalValue=0;
for(int i=0;i<hex.length();i++)
{
char hexChar=hex.charAt(i);
decimalValue=decimalValue*16+hexCharToDecimal(hexChar);
}
return decimalValue;
}

public static int hexCharToDecimal(char hexChar)
{
if(hexChar>='A'&&hexChar<='F')
return 10+hexChar-'A';
else
return hexChar-'0';//切记不能写成int类型的0，因为字符'0'转换为int时值为48
}
}