Exception in thread "main" java.lang.UnsupportedOperationException
    at java.util.AbstractList.remove(AbstractList.java:161)
    at java.util.AbstractList$Itr.remove(AbstractList.java:375)
    at java.util.AbstractCollection.remove(AbstractCollection.java:269)
    at test4.test4.main(Question4.java:21)

package test4;

import java.util.Arrays;

public class test4 {

    public static void main(String[] args) {

        String[] a = new String[]{ "A", "b", "C", "$", "$", "$", "d", "s", "w", "t", "Z",
                "r", "I", "o", "A", "b", "C", "$", "$", "$", "d", "s", "w", "t" };

        String[] b = new String[a.length];
        int num = 0;
        for(int i =0; i<a.length; i++){

            if(Character.isUpperCase(i)){
                num++;
            }
            if(Arrays.asList(a).contains("$")){

                Arrays.asList(a).remove("$");
                b[i] =a[i];
            }
        }
        System.out.println("number os uperCase is: " + num);
        System.out.println();
        System.out.println("this is the new Array: " + Arrays.toString(b));

    }

}