Practical 3 :- Practical on Set Interface

package com.hiraymca; public class Student {
int rollno; String name;
Double percentage;

public Student(int rollno, String name, Double percentage) { this.rollno = rollno;
this.name = name; this.percentage = percentage;
}
public Student()
{

}
public int getRollno() { return rollno;
}

public void setRollno(int rollno) { this.rollno = rollno;
}

public String getName() { return name;
}

public void setName(String name) { this.name = name;
}
 



public Double getPercentage() { return percentage;
}

public void setPercentage(Double percentage) { this.percentage = percentage;
}

}

package com.hiraymca;
import java.util.ArrayList; import java.util.Collection;
 import java.util.Collections;
import static  java.util.Collections.list;
 import java.util.Comparator;
import java.util.HashSet; 
import java.util.Iterator;
 import java.util.List;
import java.util.ListIterator; 
import java.util.NavigableSet; 
import java.util.Scanner; 
import java.util.TreeSet;

/**
*
* @author VIKRAM
*/
public class setExample {
public static void main(String []args)
{
String ans=null; 
int rn;
String sn; 
double per;
Scanner sc=new Scanner(System.in); 
Student s=new Student();
int choice;
//Creating set of students HashSet<Student>studentSet=new HashSet<Student>(); Iterator i;
//Creating Students

do
{
System.out.println("Menu"); System.out.println("1.Adding student"); System.out.println("2.List all students"); System.out.println("3.List in reverse direction"); System.out.println("4.Exit"); System.out.print("Enter your choice(1..4)"); choice=sc.nextInt();
int flag=0; switch(choice)
{
case 1:
System.out.print("Enter rollno"); rn=sc.nextInt(); System.out.print("Enter name"); sn=sc.next();
System.out.print("Enter percentage"); per=sc.nextDouble();
s=new Student(rn,sn,per); studentSet.add(s);
break;


case 2:
System.out.println("Rollno"+"\t"+"Name"+"\t"+"Percentage"); studentSet.forEach((s1) -> { System.out.println(s1.getRollno()+"\t"+s1.getName()+"\t"+s1.getPercentage());
});
break; case 3:

Comparator<Student> c= 

Comparator.comparing(Student::getRollno,Comparator.reverseOrder()).thenComparing(Student::getNa me,Comparator.reverseOrder());
List<Student>list=new ArrayList<>(studentSet);
list.sort(c);

System.out.println("Rollno"+"\t"+"Name"+"\t"+"Percentage"); for(Student s2:list)
{
System.out.println(s2.getRollno()+"\t"+s2.getName()+"\t"+s2.getPercentage());
}
break;
 case 4:
System.exit(0); break;

}
//adding student in HashSet
System.out.print("Do you wish to continue(y/n)"); ans=sc.next();
}while(ans.equals("Y")||ans.equals("y"));
//reteriving the student from set
}
}

com.hiraymca;
 public class Student {
int rollno; String name;
Double percentage;

public Student(int rollno, String name, Double percentage) { this.rollno = rollno;
this.name = name; this.percentage = percentage;
}
public Student()
{

}
public int getRollno() { return rollno;
}

public void setRollno(int rollno) { this.rollno = rollno;
}

public String getName() { return name;
}

public void setName(String name) { this.name = name;
}

public Double getPercentage() { return percentage;
}

public void setPercentage(Double percentage) { this.percentage = percentage;
}



}

package com.hiraymca;

import java.util.HashSet; import java.util.Iterator; import java.util.Scanner;
import java.util.function.Predicate;

/**
*
* @author VIKRAM
*/
public class setExample {
public static void main(String []args)
{
String ans=null; int rn;
String sn; double per;
Scanner sc=new Scanner(System.in); Student s=new Student();
int choice;
//Creating set of students HashSet<Student>studentSet=new HashSet<Student>(); Iterator i;
//Creating Students

do
{
System.out.println("Menu"); System.out.println("1.Adding student"); System.out.println("2.Removing student"); System.out.println("3.Search student"); System.out.println("4.List all students"); System.out.println("5.Exit"); System.out.print("Enter your choice(1..4)"); choice=sc.nextInt();
int flag=0; switch(choice)
{
case 1:
System.out.print("Enter rollno"); rn=sc.nextInt(); System.out.print("Enter name"); sn=sc.next();
System.out.print("Enter percentage"); per=sc.nextDouble();
s=new Student(rn,sn,per); studentSet.add(s);
break; case 2:
System.out.print("Enter roll no to remove element"); rn=sc.nextInt();
i=studentSet.iterator(); while(i.hasNext())
{
s=(Student)i.next(); if(s.getRollno()==rn)

{
i.	remove();
System.out.println("Element is successfully removed"); break;
}
else
{
System.out.println("Rollno="+rn);
}

}
break; case 3:
System.out.println("Enter the name of student"); sn=sc.next();
i=studentSet.iterator(); if(!i.hasNext())
{
System.out.println("List is empty");
}
while(i.hasNext())
{
s=(Student)i.next(); if(s.getName().equals(sn))
{
System.out.println("Record found");
System.out.println(s.getRollno()+" "+s.getName()+" "+s.getPercentage()); flag=1;
break;

}
if(flag!=1)
{
System.out.println("Record not found search again");
}

}
break;
 


case 4:
System.out.println("Rollno"+"\t"+"Name"+"\t"+"Percentage"); studentSet.forEach((s1) -> {
System.out.println(s1.getRollno()+" "+s1.getName()+" "+s1.getPercentage());
});
break; case 5:
System.exit(0); break;

}
//adding student in HashSet
System.out.print("Do you wish to continue(y/n)"); ans=sc.next();
}while(ans.equals("Y")||ans.equals("y"));
//reteriving the student from set
}
}

Output
Menu
1.Adding student 2.Removing student 3.Search student 4.List all students 5.Exit
Enter your choice(1..4)1 Enter rollno 1
Enter name AAA
Enter percentage 99.98
Do you wish to continue(y/n)y Menu
1.Adding student 2.Removing student 3.Search student 4.List all students 5.Exit
Enter your choice(1..4)1
 


Enter rollno 2 Enter name BBB
Enter percentage 89.45
Do you wish to continue(y/n)y Menu
1.Adding student 2.Removing student 3.Search student 4.List all students 5.Exit
Enter your choice(1..4)1 Enter rollno 3
Enter name CCC
Enter percentage55.24
Do you wish to continue(y/n)y Menu
1.Adding student 2.Removing student 3.Search student 4.List all students 5.Exit
Enter your choice(1..4)3 Enter the name of student CCC
Record found 3 CCC 55.24
Do you wish to continue(y/n)y Menu
1.Adding student 2.Removing student 3.Search student 4.List all students 5.Exit
Enter your choice(1..4)4 Rollno Name Percentage 3 CCC 55.24
2 BBB 89.45
1 AAA 99.98
 


Do you wish to continue(y/n)y Menu
1.Adding student 2.Removing student 3.Search student 4.List all students 5.Exit
Enter your choice(1..4)2
Enter roll no to remove element2 Rollno=2
Element is successfully removed Do you wish to continue(y/n)y Menu
1.	Adding student 2.Removing student 3.Search student 4.List all students 5.Exit
Enter your choice(1..4)4 Rollno Name Percentage 3 CCC 55.24
1 AAA 99.98
Do you wish to continue(y/n)n