.Equals() not working while iterating hashmap

Question

enter image description hereI have a hashmap which I need to compare values of the String array to certain strings and remove those which are equal. In this instance I know the String [] at a certain index = "RES", but when I iterate through the if (equality) statement returns false each time. Do I have to worry about overriding .equals() when simply extending hashmap? What is wrong with the if statement?

public void filter(){
    Iterator<Map.Entry<String, String[]>> iter = this.entrySet().iterator();
    while(iter.hasNext()){
        Map.Entry<String,String[]> entry = iter.next();
        String[] current = entry.getValue();
        if(current[0].trim().equalsIgnoreCase("RES")){  
            this.remove(entry.getKey());
        }          
    }
}

Answer 1

Replace:

this.remove(entry.getKey());

With:

iter.remove();