Adding all the elements of a LinkedHashSet to another LinkedHashSet

 

import java.util.Iterator;

import java.util.LinkedHashSet;

import java.util.Set;

import javax.management.monitor.StringMonitor;

public class LinkedHashSetAddAll {

public static void main(String[] args) {

// creating our LinkedHashSet

Set<String> lhs = new LinkedHashSet<>();

// adding element to our set

// insertion order is maintained here

lhs.add("Neha");

lhs.add("Nisha");

lhs.add("Nishu");

lhs.add("Rekha");

lhs.add("Madhu");

lhs.add("Disha");

lhs.add("Tara");

lhs.add("Tara"); // duplicate element can't be added

// creating another LinkedHashSet

Set<String> lhs1 = new LinkedHashSet<>();

lhs1.add("Reena");

lhs1.add("Sweety");

lhs1.add("Sheetal");

// Adding all elements of lhs to lhs1

System.out.println("After invoking addAll() method");

lhs.addAll(lhs1);

System.out.println(lhs);

}

}

Removing all elements from a LinkedHashSet

 

import java.util.Iterator;

import java.util.LinkedHashSet;

import java.util.Set;

import javax.management.monitor.StringMonitor;

public class LinkedHashSetRemoveAll {

public static void main(String[] args) {

// creating our LinkedHashSet

Set<String> lhs = new LinkedHashSet<>();

// adding element to our set

// insertion order is maintained here

lhs.add("Neha");

lhs.add("Nisha");

lhs.add("Nishu");

lhs.add("Rekha");

lhs.add("Madhu");

lhs.add("Disha");

lhs.add("Tara");

lhs.add("Tara"); // duplicate element can't be added

// creating another LinkedHashSet

Set<String> lhs1 = new LinkedHashSet<>();

lhs1.add("Neha");

lhs1.add("Nisha");

lhs1.add("Madhu");

System.out.println("Before invoking removeAll() method,lhs and lhs1");

System.out.println(lhs);

System.out.println(lhs1);

lhs.removeAll(lhs1);

System.out.println("After invoking removeAll() method,lhs");

System.out.println(lhs);

// deleting all elements

lhs.clear();

lhs1.clear();

System.out.println("After invoking clear() method,lhs and lhs1 :");

System.out.println(lhs);

System.out.println(lhs1);

}

}

Removing element from a LinkedHashSet

import java.util.Iterator;

import java.util.LinkedHashSet;

import java.util.Set;

import javax.management.monitor.StringMonitor;

public class LinkedHashSetRemove {

public static void main(String[] args) {

// creating our LinkedHashSet

Set<String> lhs = new LinkedHashSet<>();

// adding element to our set

// insertion order is maintained here

lhs.add("Neha");

lhs.add("Nisha");

lhs.add("Nishu");

lhs.add("Rekha");

lhs.add("Madhu");

lhs.add("Disha");

lhs.add("Tara");

lhs.add("Tara"); // duplicate element can't be added

System.out.println("Before invoking remove() method");

System.out.println(lhs);

lhs.remove("Tara");

System.out.println("After invoking remove() method");

System.out.println(lhs);

}

}

Adding element to a LinkedHashSet

 

import java.util.Iterator;

import java.util.LinkedHashSet;

import java.util.Set;

import javax.management.monitor.StringMonitor;

public class LinkedHashSetMethods {

public static void main(String[] args) {

// creating our LinkedHashSet

Set<String> lhs = new LinkedHashSet<>();

// adding element to our set

// insertion order is maintained here

lhs.add("Neha");

lhs.add("Nisha");

lhs.add("Nishu");

lhs.add("Rekha");

lhs.add("Madhu");

lhs.add("Disha");

lhs.add("Tara");

lhs.add("Tara"); // duplicate element can't be added

// iterating using Iterator

Iterator<String> itr = lhs.iterator();

while (itr.hasNext()) {

System.out.println(itr.next());

}

}

}

Converting a Set to an Array

 

import java.util.Set;

import java.util.HashSet;

public class SetToArray {

public static void main(String[] args) {

// creating our set

// set internally uses hashmap

Set<String> set = new HashSet<>();

// adding element to our set

set.add("Gunjan");

set.add("Rehana");

set.add("Kiara");

set.add("Kayra");

set.add("Varsha");

set.add("Sayra");

set.add("Rehana");

// creating an array of object type

Object[] arr = set.toArray();

// getting size of set and array

System.out.println("Size of set is = " + set.size());

System.out.println("Length of Array = " + arr.length);

// printing array using for each loop

System.out.println("Printing Array using for each loop :");

for (Object o : arr) {

System.out.print(o + " ");

}

System.out.println();

System.out.println("Printing Array using for loop :");

// priting array using for loop

for (int i = 0; i < arr.length; i++) {

System.out.print(arr[i] + " ");

}

}

}

Retaining all element from one a set to another set

 

import java.util.Set;

import java.util.HashSet;

public class SetRetains {

public static void main(String[] args) {

// creating our set

// set internally uses hashmap

Set<String> set = new HashSet<>();

// adding element to our set

set.add("Gunjan");

set.add("Rehana");

set.add("Kiara");

set.add("Kayra");

set.add("Varsha");

set.add("Sayra");

set.add("Rehana");

Set<String> set1 = new HashSet<>();

set1.add("Rehana");

set1.add("Kayra");

set1.add("Gunjan");

set.retainAll(set1);

System.out.println(set);

System.out.println(set1);

}

}

Checking if the set is emtpy or not

import java.util.Set;

import java.util.HashSet;

public class SetIsEmpty {

public static void main(String[] args) {

// creating our set

// set internally uses hashmap

Set<String> set = new HashSet<>();

// adding element to our set

set.add("Gunjan");

set.add("Rehana");

set.add("Kiara");

set.add("Kayra");

set.add("Varsha");

set.add("Sayra");

set.add("Rehana");

Set<String> set1 = new HashSet<>();

set1.add("Rehana");

set1.add("Kayra");

set1.add("Gunjan");

Set<String> set2 = new HashSet<>();

System.out.println(set.isEmpty());

System.out.println(set1.isEmpty());

System.out.println(set2.isEmpty());

}

}

Searching an element or set of element in another Set using contains() method

 

import java.util.Set;

import java.util.HashSet;

public class SetContains {

public static void main(String[] args) {

// creating our set

// set internally uses hashmap

Set<String> set = new HashSet<>();

// adding element to our set

set.add("Gunjan");

set.add("Rehana");

set.add("Kiara");

set.add("Kayra");

set.add("Varsha");

set.add("Sayra");

set.add("Rehana");

Set<String> set1 = new HashSet<>();

set1.add("Rehana");

set1.add("Kayra");

set1.add("Gunjan");

Set<String> set2 = new HashSet<>();

set2.add("Rehana");

set2.add("Kayra");

set2.add("Gunjan");

set2.add("Ravisha");

System.out.println(set.contains("Kiara"));

System.out.println(set1.contains("Varsha"));

System.out.println(set.containsAll(set1));

System.out.println(set1.containsAll(set2));

}

}

Removing elements from a HashSet using different methods

import java.util.Set;

import java.util.HashSet;

public class SetRemove {

public static void main(String[] args) {

// creating our set

// set internally uses hashmap

Set<String> set = new HashSet<>();

// adding element to our set

set.add("Gunjan");

set.add("Rehana");

set.add("Kiara");

set.add("Kayra");

set.add("Varsha");

set.add("Sayra");

set.add("Rehana");

Set<String> set1 = new HashSet<>();

set1.add("Rehana");

set1.add("Kayra");

set1.add("Gunjan");

System.out.println("Before invoking remove() method the set is");

System.out.println(set);

set.remove("Varsha");

System.out.println("After invoking remove() method the set is");

System.out.println(set);

// set.clear();

System.out.println("After invoking remove clear() the set is");

System.out.println(set);

System.out.println("After invoking addAll() method");

set.removeAll(set1);

System.out.println(set);

System.out.println(set1);

}

}

Adding element in a Set(HashSet)

import java.util.HashSet;

import java.util.Set;

import java.util.Iterator;

public class SetAdd {

public static void main(String[] args) {

// creating our set

// set internally uses hashmap

Set<String> set = new HashSet<>();

// adding element to our set

set.add("Gunjan");

set.add("Rehana");

set.add("Kiara");

set.add("Kayra");

set.add("Varsha");

set.add("Sayra");

set.add("Rehana");

// iterating using iterator and printing the elements

Iterator itr = set.iterator();

while (itr.hasNext()) {

System.out.println(itr.next());

}

}

}