adding-customized-sort-on-our-employee-class

Java/CustomizedSort.java

@@ -0,0 +1,72 @@
+// comparable & comparator interface in our own Employee class
+
+import java.util.*;
+class Employee implements Comparable
+{
+	int id;
+	String name;
+	Employee(int id, String name)
+	{
+		this.id=id;
+		this.name=name;
+	}
+	public int compareTo(Object obj)
+	{
+		int id1,id2;
+		id2=((Employee)obj).id;		// id2 is the id of object2
+		id1=this.id;			// id1 is the id of object1
+		if(id1>id2)
+		{
+			return +1;
+		}
+		else if(id1<id2)
+		{
+			return -1;
+		}
+		else
+		{
+			return 0;
+		}
+	}
+	public String toString()
+	{
+		return name+"--"+id;
+	}
+}
+class Main
+{
+	public static void main(String ab[])
+	{
+		TreeSet<Employee> t1=new TreeSet<Employee>();		// Comparable interface
+		Employee e1=new Employee(4,"Ayush");
+		Employee e2=new Employee(1,"Anish");
+		Employee e3=new Employee(3,"Atul");
+		Employee e4=new Employee(5,"Animesh");
+		Employee e5=new Employee(2,"Dhanwan");
+		Employee e6=new Employee(6,"Jaini");
+		t1.add(e1);						// no comparison needed as it is first element
+		t1.add(e2);						// e2=obj1, e1=obj2
+		t1.add(e3);
+		t1.add(e4);
+		t1.add(e5);
+		t1.add(e6);
+		System.out.println("Using comparable interface="+t1);
+		TreeSet<Employee> t2=new TreeSet<Employee>(new MyComparator());		// Comparator interface
+		t2.add(e1);
+		t2.add(e2);
+		t2.add(e3);
+		t2.add(e4);
+		t2.add(e5);
+		t2.add(e6);
+		System.out.println("Using comparator interface="+t2);
+	}
+}
+class MyComparator implements Comparator
+{
+	public int compare(Object o1,Object o2)
+	{
+		Employee e1=(Employee)o1;
+		Employee e2=(Employee)o2;
+		return e1.name.compareTo(e2.name);
+	}
+}