student

=

new

ArrayList & lt student & gt ();

Add: students.add (student);

Deleting: using iterators

iterator

=

students . iterator()；

Iteration finds that the specified student number executes the iterator. Remove (); Loop terminal

Change: Iterator such as delete is used to traverse, and the specified student number is found to execute get, set to modify the attribute, and the loop ends.

Check: strengthen the for loop, keep the student number unchanged, and return to student.