StudentManager

import java.util.ArrayList;

/**
 * This class represents multiple students.
 */
public class StudentManager {
    private ArrayList<Student> students;

    /**
     * This is the constructor for the StudentManager class.
     * 
     * @param students The students to add to the database.
     */
    public StudentManager() {
        students = new ArrayList<Student>();
    }

    /**
     * This method adds a student to the database.
     */
    public void addStudent(Student student) {
        students.add(student);
    }
    

    /**
     * This method returns a student from the database.
     * 
     * @param id The ID of the student to return.
     * @return The student with the given ID.
     */
    public Student getStudent(String id) {
        for (Student student : students) {
            if (student.getID().equals(id)) {
                return student;
            }
        }
        return null;
    }
    
    
    /**
     * This method removes a student from the database.
     * 
     * @param student The student to remove.
     */
    public void removeStudent(Student student) {
        students.remove(student);
    }

    /**
     * This method modifies a student's information.
     * 
     * @param student The student to modify.
     * @param firstName The new first name of the student.
     * @param lastName The new last name of the student.
     * @param id The new ID of the student.
     */
    public void modifyStudent(Student student, String firstName, String lastName, String id) {
        student.setFirstName(firstName);
        student.setLastName(lastName);
        student.setID(id);
    }

    /**
     * This method returns all students in the database.
     * 
     * @return All students in the database.
     */
    public ArrayList<Student> getStudents() {
        return students;
    }
}