Anagrams or not in Java

import java.io.*;
class CheckAnagram
{
boolean anagram(String a, String b)

{
if (a.length() != b.length())
return false;
int[] alpha= new int[256];
int chars = 0;
int num = 0;
char[] a_array = a.toCharArray();
for (char c : a_array)
{
if (alpha[c] == 0) ++chars;
++alpha[c];
}
for (int i = 0; i < b.length(); ++i)
{
int c = (int) b.charAt(i);
if (alpha[c] == 0)
{
return false;
}
--alpha[c];
if (alpha[c] == 0)
{
++num;
if (num == chars)
{
return i == b.length() - 1;
}
}
}
return false;
}
}
class AnagramFinder
{
public static void main (String[] args)
{
CheckAnagram c=new CheckAnagram();
System.out.println ("Enter the first string");
String str1 = "";
String str2 = "";
InputStreamReader input1 = new InputStreamReader(System.in);
BufferedReader r1 = new BufferedReader(input1);
try
{
str1 = r1.readLine();

System.out.println ("Enter the second string");
str2 = r1.readLine();
}
catch(Exception e){}
boolean value =c. anagram(str1,str2);
if(value == true)
System.out.println("The string are anagrams.");
else
System.out.println("The string are NOT anagrams. ");
}

}