HashMap.java

//Student Class
class Student {
	String name;
	Student(String name) {
		this.name = name;
	}
	@Override
	public String toString() {
		return "Student [name=" + name + "]";
	}
	
}

//HashMap
//HashMap is implemented as a hash table, and there is no ordering on keys or values.
HashMap<Student, Integer> students = new HashMap<Student, Integer>();
		
	Student s1 = new Student("John");
	Student s2 = new Student("Mark");
	Student s3 = new Student("Daniel");
	Student s4 = new Student("Joseph");
		
	students.put(s1, 10);
	students.put(s2, 4);
	students.put(s3, 8);
	students.put(s4, 5);
		
	for (Entry<Student, Integer> entry : students.entrySet()) {
		System.out.println(entry.getKey().toString() + " - " + entry.getValue());
	}
}

my student class has id, name and address. i would like to take Student id as the key for hashmap and other details of student as the value.