/* package whatever; // don't place package name! */
 
import java.util.*;
import java.lang.*;
import java.io.*;
import java.util.regex.*;
/* Name of the class has to be "Main" only if the class is public. */
class Ideone
{
	public static void main (String[] args) throws java.lang.Exception
	{
 
		String s = "(A + H + (B + (C + D - E) - F) - (G + H - I))";
		String pattern = "\\(([^()]*)\\)";
		String old = s;
		while (Pattern.compile(pattern).matcher(s).find() &&
		        !s.matches(pattern)){
			s = s.replaceAll(pattern, "X");
			if (old.equals(s)) {
				break;
			} else {
				old = s;
			}
		} 
		System.out.println(s); 
	}
}

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