Balanced String

 import java.util.Stack;

public class BalancedString {

    public static void main(String[] args) {
        String check="({}{}([{}]))";
        System.out.println(isBalanced(check));

    }
    public static boolean isBalanced(String str){
        char[] arr=str.toCharArray();
        Stack<Character> st=new Stack<>();
        for (Character ch:arr
             ) {
            if(ch=='['||ch=='{'||ch=='(')
                st.push(ch);
            else{
                char last=st.pop();
                if(last=='{'&&ch!='}')
                    return false;
                else if(last=='('&& ch!=')')
                    return false;
                else if(last=='['&&ch!=']')
                    return false;
            }

        }
        return st.size()==0;
    }
}