/* 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 = "ex1 , [ex2 , ex3 ] , ex 4 , ex 4, [ex , ex ]";
		String pat = ",(?![^\\[]*])";
		String[] result = s.split(pat);
		System.out.println(Arrays.toString(result));
	}
}

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