java
java
a month ago
2.4 kB
1
Indexable
Never
package student.ans; import java.util.HashMap; import java.util.Map; public class MgmtAppAns { public static void main(String[] args) { StudentDatabase database = new StudentDatabase(); // Demonstrate adding, updating, and listing students Student student1 = new Student("Alice", 20, "Computer Science"); Student student2 = new Student("Bob", 21, "Engineering"); database.addStudent(student1); database.addStudent(student2); Student retrievedStudent = database.getStudent(1); retrievedStudent.setName("Alex"); database.updateStudent(retrievedStudent); database.listStudents(); } } class StudentDatabase { private Map<Integer, Student> students = new HashMap<>(); private int nextId = 1; public void addStudent(Student student) { student.setId(nextId); students.put(nextId, student); nextId++; } public Student getStudent(int i) { return students.get(i); } public void updateStudent(Student retrievedStudent) { students.put(retrievedStudent.getId(), retrievedStudent); } public void listStudents() { students.values().forEach(x -> { System.out.println(x.toString()); }); } } class Student { private int id; private String name; private int age; private String course; public Student(String name, int age, String course) { this.name = name; this.age = age; this.course = course; } public int getId() { return id; } public void setId(int id) { this.id = id; } public String getName() { return name; } public void setName(String name) { this.name = name; } public int getAge() { return age; } public void setAge(int age) { this.age = age; } public String getCourse() { return course; } public void setCourse(String course) { this.course = course; } @Override public String toString() { return "Student{" + "id=" + id + ", name='" + name + '\'' + ", age=" + age + ", course='" + course + '\'' + '}'; } }