How do i display the Array List without [], and next lines instead of displaying on [1,2,3]

Here is my code

 private List[] split(ArrayList aList) {
        
    ArrayList first = new ArrayList(); 
    ArrayList second = new ArrayList();
    
    int size = aList.size(); 
    
    for (int i = 0; i < size / 2; i++) 
             first.add(aList.get(i));
    
    for (int i = size / 2; i < size; i++) 
            second.add(aList.get(i));
    
    return new List[] { first, second };
        
}

Collections.shuffle(list);

List[] lists = split(list); 	

jTextArea2.append(lists[0].toString());
jTextArea3.append(lists[1].toString());

This is how it looks like now... i want the list in Team A and Team B to be displayed list in Uploaded list

Add each element separately:

for (int i = 0; i < lists[0].size(); i++) {
    jTextArea2.append(lists[0].get(i).toString());
    jTextArea2.append("\n");
} 

You can use joining collector from Streams api.

jTextArea2.append(lists[0].stream()
                      .map(Object::toString)
                      .collect(Collectors.joining("\n")));