How to override the toString method of ArrayList in Java?

I want to use the toString () method for ArrayList in Java However, even if I add such toString () to the class containing ArrayList, I can't get its work

@Override
public String toString() {
    String result = "+";
    for (int i = 0; i < list.size(); i++) {
        result += " " + list.get(i);
    }
    return result;
}

When I list like this When toString () calls my ArrayList, I still get the default representation Did I miss anything?

Solution

You should do something similar

public static String listToString(List<?> list) {
    String result = "+";
    for (int i = 0; i < list.size(); i++) {
        result += " " + list.get(i);
    }
    return result;
}

And pass the list as a parameter of listtostring() You can technically extend ArrayList (using anonymous classes or concrete) and implement toString yourself, but this seems unnecessary