Java.util.LinkedList.get(), getFirst(), getLast() in Java
The conventional method allowing to get the element at particular index is get(). Though in LinkedList its never possible to achieve this without complete traversal, but this method allows the same. Three variants present, all of which are discussed in this article with Exceptions as well.
1. get(int index) : This method returns the element at the specified position in this list.
Declaration : public E get(int index) Parameters : index : index of the element to return Return Value : This method returns the element at the specified position in this list Exception IndexOutOfBoundsException : if the index is out of range
// Java code to demonstrate the working // of get(int index) in linked list import java.util.*; public class LinkedListget1 { public static void main(String[] args) { // declaring a LinkedList LinkedList<String> list = new LinkedList<String>(); // adding elements using add() list.add( "Geeks" ); list.add( "4" ); list.add( "Geeks" ); list.add( "8" ); // printing the whole list System.out.println( "The elements in List are : " + list); // using get() to print element at index 3 // prints 8 System.out.println( "Element at index 3 is : " + list.get( 3 )); } } |
Output :
The elements in List are : [Geeks, 4, Geeks, 8] Element at index 3 is : 8
2. getFirst() : This method returns the first element in this list.
Declaration : public E getFirst() Return Value : This method returns the first element in this list Exceptions : NoSuchElementException : if this list is empty
// Java code to demonstrate the working // of getFirst() in linked list import java.util.*; public class LinkedListget2 { public static void main(String[] args) { // declaring a LinkedList LinkedList<String> list = new LinkedList<String>(); // adding elements using add() list.add( "Geeks" ); list.add( "4" ); list.add( "Geeks" ); list.add( "8" ); // printing the whole list System.out.println( "The elements in List are : " + list); // using get() to print element at first index // prints "Geeks" System.out.println( "Element at 1st index is : " + list.getFirst()); } } |
Output :
The elements in List are : [Geeks, 4, Geeks, 8] Element at 1st index is : Geeks
3. getLast() : This method returns the last element in this list.
Declaration : public E getLast() Return Value : This method returns the last element in this list Exceptions : NoSuchElementException : if this list is empty
// Java code to demonstrate the working // of getLast() in linked list import java.util.*; public class LinkedListget3 { public static void main(String[] args) { // declaring a LinkedList LinkedList<String> list = new LinkedList<String>(); // adding elements using add() list.add( "Geeks" ); list.add( "4" ); list.add( "Geeks" ); list.add( "8" ); // printing the whole list System.out.println( "The elements in List are : " + list); // using get() to print element at last index // prints "8" System.out.println( "Element at last index is : " + list.getLast()); } } |
Output:
The elements in List are : [Geeks, 4, Geeks, 8] Element at last index is : 8
1. IndexOutOfBoundException
// Java code to demonstrate the Exceptions // of get() import java.util.*; public class LinkedListExcep1 { public static void main(String[] args) { // declaring a LinkedList LinkedList<String> list = new LinkedList<String>(); // adding elements using add() list.add( "Geeks" ); list.add( "4" ); list.add( "Geeks" ); list.add( "8" ); // Trying to get element at index 7 // throws exception System.out.println( "The element at index 7 is : " + list.get( 7 )); } } |
Output :
No Output
Runtime Error :
Exception in thread "main" java.lang.IndexOutOfBoundsException: Index: 7, Size: 4 at java.util.LinkedList.checkElementIndex(LinkedList.java:555) at java.util.LinkedList.get(LinkedList.java:476) at LinkedListExcep1.main(LinkedListExcep1.java:22)
2. NoSuchElementException
// Java code to demonstrate the Exceptions // of getFirst() import java.util.*; public class LinkedListExcep2 { public static void main(String[] args) { // declaring a LinkedList LinkedList<String> list = new LinkedList<String>(); // Trying to get first element at index 7 // throws exception System.out.println( "The first element of list is : " + list.getFirst()); } } |
Output :
No Output
Runtime Error :
Exception in thread "main" java.util.NoSuchElementException at java.util.LinkedList.getFirst(LinkedList.java:244) at LinkedListExcep2.main(LinkedListExcep2.java:15)
This article is contributed by Astha Tyagi. If you like GeeksforGeeks and would like to contribute, you can also write an article using contribute.geeksforgeeks.org or mail your article to contribute@geeksforgeeks.org. See your article appearing on the GeeksforGeeks main page and help other Geeks.
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