Which class is the best for reading input from user during runtime in JAVA ?

Question

Like I have a tiny java game in which name of movie is hidden and we have to guess that. Here if your guess is correct that letter will appear at correct place and if wrong you will loose one chance. When we run the code, it runs sometimes without taking any input which it should not do. The java code is following.

import java.util.*;
import java.io.*;
import java.lang.*;
class StrDemo
{
    static StringBuilder change(StringBuilder sb)
    {
        StringBuilder sb1=new StringBuilder("");
        int len=sb.length();
        for(int i=0;i<len;i++)
        {
            if(sb.charAt(i)!=' ')
                sb1.append("*");
            else
                sb1.append(" ");
        }
        return sb1;
    }

    public static void main(String a[])
        throws Exception
        {
            StringBuilder sb2=new StringBuilder("hum sath sath hain");
            StringBuilder sb3=change(sb2);
            int j=0;
            StringBuilder sb4=new StringBuilder("Bollywood");

            while(true)
            {
                System.out.println(sb4);
                System.out.println(sb3);
                System.out.println("Enter Char");

                Scanner sc=new Scanner(System.in);

                char ch=(char)System.in.read();
                int c=0;
                int len=sb2.length();

                for(int i=0;i<len;i++)
                {
                    if(sb2.charAt(i)==ch)
                    {
                        sb3.setCharAt(i,ch);
                        c++;
                    }
                }

                if(c==0)
                    sb4.setCharAt(j++,'*');

                if(sb4.equals("*********"))
                    System.out.println("you lost...");
                else if(sb3.equals("hum sath sath hain"))
                    System.out.println("...u won");
            }   
        }
}