How to Delete User Defined Objects from LinkedHashSet?
The LinkedHashSet is an ordered version of HashSet that maintains a doubly-linked List across all elements. When the iteration order is needed to be maintained this class is used. When iterating through a HashSet the order is unpredictable, while a LinkedHashSet lets us iterate through the elements in the order in which they were inserted.
Example:
Input: ["Geeks", "for", "geeks"]
DELETE = "geeks"
Output: "Geeks"
"for"
Input: [1, 2, 3, 4, 5]
DELETE = 2
Output: [1, 3, 4, 5]
There are two ways by which we can delete elements from LinkedHashSet:
- Using remove() Method
- Using clear() Method
Method 1: remove() methods are used to delete a specific element from a LinkedHashSet object.
Syntax:
LinkedHashSet.remove(Object O)
Parameters: The parameter O is of the type of LinkedHashSet and specifies the element to be removed from the LinkedHashSet.
Return Value: This method returns True if the specified element is present in the LinkedHashSet otherwise it returns False.
// Java program to delete user defined
// objects from LinkedHashSet
import java.util.*;
public class GFG {
public static void main(String[] args)
{
LinkedHashSet<String> lset
= new LinkedHashSet<String>();
// add elements to HashSet
lset.add("GEEKS");
lset.add("FOR");
lset.add("GEEKS");
// Displaying the LinkedHashSet Before Deleting
System.out.println("Before deleting an element :");
System.out.println(lset);
// remove() method to delete an element from
// LinkedHashSet
lset.remove("FOR");
// Displaying the LinkedHashSet After Deleting
System.out.println("After deleting an element:");
System.out.println(lset);
}
}
// Java program to delete user defined // objects from LinkedHashSetimport java.util.*;public class GFG { public static void main(String[] args) { LinkedHashSet<String> lset = new LinkedHashSet<String>(); // add elements to HashSet lset.add("GEEKS"); lset.add("FOR"); lset.add("GEEKS"); // Displaying the LinkedHashSet Before Deleting System.out.println("Before deleting an element :"); System.out.println(lset); // remove() method to delete an element from // LinkedHashSet lset.remove("FOR"); // Displaying the LinkedHashSet After Deleting System.out.println("After deleting an element:"); System.out.println(lset); }}Output
Before deleting an element : [GEEKS, FOR] After deleting an element: [GEEKS]
Method 2: clear() method is used to delete all element from LinkedHashSet. The set will be empty after this call returns.
Syntax:
public void clear()
Return Value: This method does not return anything.
Below are the examples to illustrate the clear() method.
// Java program to delete elements
// from LinkedHashSet
import java.util.*;
import java.util.LinkedHashSet;
public class GFG {
public static void main(String[] args)
{
LinkedHashSet<String> l_set
= new LinkedHashSet<String>();
// add elements to HashSet
l_set.add("GEEKS");
l_set.add("FOR");
l_set.add("GEEKS");
// Displaying the LinkedHashSet Before Deleting
System.out.println("Before deleting an element :");
System.out.println(l_set);
// clear() method to delete all element from
// LinkedHashSet
l_set.clear();
// Displaying an empty LinkedHashSet After Deleting
System.out.println("After deleting all element:");
System.out.println(l_set);
}
}
// Java program to delete elements// from LinkedHashSetimport java.util.*;import java.util.LinkedHashSet;public class GFG { public static void main(String[] args) { LinkedHashSet<String> l_set = new LinkedHashSet<String>(); // add elements to HashSet l_set.add("GEEKS"); l_set.add("FOR"); l_set.add("GEEKS"); // Displaying the LinkedHashSet Before Deleting System.out.println("Before deleting an element :"); System.out.println(l_set); // clear() method to delete all element from // LinkedHashSet l_set.clear(); // Displaying an empty LinkedHashSet After Deleting System.out.println("After deleting all element:"); System.out.println(l_set); }}Output
Before deleting an element : [GEEKS, FOR] After deleting all element: []
