String Reverse without String API

class StringReverse
{
    public static void main(String[] args) throws java.io.IOException
    {
        int str[] = new int[100];
        int i=0,j;
        System.out.println("Enter a string");
        while(true)
        {
            str[i]=System.in.read();
            if(str[i++]==13)
                break;
        }
        String reversed="",simple = new String(str,0,i-1);
        System.out.println(simple);

        // now reversing the string
        for(j=i-1;j>=0;j--)
            reversed+=((char)str[j]);
        System.out.println(reversed);
    }
}