Notes

import java.util.*;
class Employee implements Comparable
{
String name;
int eid;
Employee(String name,int eid)
{
this.name=name;
this.eid=eid;
}
public String toString()
{
return name+"----"+eid;
}
public int compareTo(Object o)
{
int eid1=this.eid;
int eid2=((Employee)o).eid;
if(eid1<eid2)
{
return -1;
}
else if(eid>eid2)
{
return 1;
}
else return 0;
}
}
class CompComp
{
public static void main(String[] args)
{
Employee e1=new Employee("nag",100);
Employee e2=new Employee("balaiah",200);

Employee e3=new Employee("chiru",50);
Employee e4=new Employee("venki",150);
Employee e5=new Employee("nag",100);
TreeSet t1=new TreeSet();
t1.add(e1);
t1.add(e2);
t1.add(e3);
t1.add(e4);
t1.add(e5);
System.out.println(t1);//[chiru----50, nag----100, venki----150, balaiah----200]
TreeSet t2=new TreeSet(new MyComparator());
t2.add(e1);
t2.add(e2);
t2.add(e3);
t2.add(e4);
t2.add(e5);
System.out.println(t2);//[balaiah----200, chiru----50, nag----100, venki----150]
}
}
class MyComparator implements Comparator
{
public int compare(Object obj1,Object obj2)
{
Employee e1=(Employee)obj1;
Employee e2=(Employee)obj2;
String s1=e1.name;
String s2=e2.name;
return s1.compareTo(s2);
}
}