In this tutorial we will learn about HashSet remove method in java . Java HashSet remove method use to remove element. We will see different method to remove element from HashSet using hashset remove() method .
Syntax :
public boolean remove(Object o) {
}Removes the specified element from this HashSet if it is present. More formally, removes an element e such that (o==null ? e==null : o.equals(e)), if this HashSet contains such an element.
Parameter : The object/element to be removed from this HashSet. Return Value : It returns boolean value .
Example 1 : HashSet Remove() method – Element Present
In this example , We will create HashSet of String and add elements into HashSet using add() method. We shall then use remove method to remove element php from HashSet .
public class HashSetRemove {
public static void main(String[] args) {
// Constructs a new, empty set
HashSet<String> hashSet = new HashSet<String>();
// add element in it
hashSet.add("java");
hashSet.add("php");
hashSet.add("android");
// display the element
System.out.println("element in hashset =" + hashSet);
/* * Removes the specified element from set
if it is present */
boolean isElementRemoved = hashSet.remove("php");
System.out.println(" is Element removed From HashSet ? "+ isElementRemoved );
System.out.println("After Remove element hashset is =" + hashSet);
}
}Output:
element in hashset =[java, android, php]
is Element removed From HashSet ? true
After Remove element hashset is =[java, android]Example 2 : HashSet Remove() method – Element not Present
In this example , We will initialize HashSet of String . Then we shall use remove method to remove element from HashSet. But element is not present in HashSet , So remove() method return false.
import java.util.HashSet;
public class HashSetRemove1 {
public static void main(String[] args) {
// Constructs a new, empty set
HashSet<String> hashSet = new HashSet<String>();
// add element in it
hashSet.add("java");
hashSet.add("php");
hashSet.add("android");
// display the element
System.out.println("element in hashset =" + hashSet);
boolean isElementRemoved = hashSet.remove("html");
System.out.println(" is Element removed From HashSet ? "+ isElementRemoved );
System.out.println("After Remove element hashset is =" + hashSet);
}
}Output:
element in hashset =[java, android, php]
is Element removed From HashSet ? false
After Remove element hashset is =[java, android, php]Example 2 : HashSet Remove() method – Integer Elements
In this example we will initialize HashSet Of Integer type . Then we shall remove element for HashSet using remove() method.
import java.util.HashSet;
public class HashSetRemove2 {
public static void main(String[] args) {
// Constructs a new, empty set
HashSet<Integer> hashSet = new HashSet<Integer>();
// add element in it
hashSet.add(10);
hashSet.add(20);
hashSet.add(30);
// display the element
System.out.println("element in hashset =" + hashSet);
boolean isElementRemoved = hashSet.remove(30);
System.out.println(" is Element removed From HashSet ? "
+ isElementRemoved);
System.out.println("After Remove element hashset is =" + hashSet);
}
}Output:
element in hashset =[20, 10, 30]
is Element removed From HashSet ? true
After Remove element hashset is =[20, 10]In this tutorial we leaned about java hashset remove() method . We have see different example for remove() method of HashSet .You can see more java HashSet Example f or practice .