This is the minimized code to remove the duplicacy from Generic Type Data Class

RemoveDuplicacy.java

package com;

import java.util.ArrayList;
import java.util.Collection;
import java.util.HashSet;

public class Foo {

  public static void main(String args[]) {
		ArrayList<User> usersList = new ArrayList<User>();
		usersList.clear();

		User user = new User();
		user.setName("A");
		user.setId("1"); // duplicate
		usersList.add(user);

		user = new User();
		user.setName("A");
		user.setId("1"); // duplicate
		usersList.add(user);

		user = new User();
		user.setName("AB");
		user.setId("2"); // duplicate
		usersList.add(user);

		user = new User();
		user.setName("C");
		user.setId("4");
		usersList.add(user);

		user = new User();
		user.setName("A");
		user.setId("1"); // duplicate
		usersList.add(user);

		user = new User();
		user.setName("A");
		user.setId("2"); // duplicate
		usersList.add(user);

		Collection<User> userList = new HashSet<User>(usersList);
 		for (User userObject : userList) {
			System.out.println(" Name  :" + userObject.getName() + "\n Id  :"
					+ userObject.getId() + "\n");

		}

		 

	}

}

	class User {
		private String name;
		private String id;
	
		/**
		 * @param name
		 *            the name to set
		 */
		public void setName(String name) {
			this.name = name;
		}
	
		/**
		 * @return the name
		 */
		public String getName() {
			return name;
		}
	
		/**
		 * @param id
		 *            the id to set
		 */
		public void setId(String id) {
			this.id = id;
		}
	
		/**
		 * @return the id
		 */
		public String getId() {
			return id;
		}

	@Override
	public int hashCode() {

		final int prime = 31;
		int result = 1;
		result = prime * result + ((id == null) ? 0 : id.hashCode());
		return result;

	}

	@Override
	public boolean equals(Object obj) {

		if (this == obj)
			return true;

		if (obj == null)
			return false;

		if (getClass() != obj.getClass())
			return false;

		User other = (User) obj;

		if (id == null) {
			if (other.id != null)
				return false;

		} else if (!id.equals(other.id))
			return false;

		return true;

	}
}