Java Program to Get Elements of a LinkedList (original) (raw)

Last Updated : 27 Nov, 2020

Linked List is a linear data structure, in which the elements are not stored at the contiguous memory locations. Here, the task is to get the elements of a LinkedList.

1. We can use get(int variable) method to access an element from a specific index of LinkedList:

In the given example, we have used the get(i) method. Here, the method returns the element which is at the i th index.

Syntax:

LinkedList.get(int index)

Parameters: The parameter index is of integer data type that specifies the position or index of the element to be fetched from the LinkedList.

Return Value: The method returns the element present at the position specified by the parameter index.

Java `

// Java program to get the elements of Linkedlist

import java.io.*; import java.util.LinkedList; class GFG { public static void main(String[] args) {

    // Creating LinkedList
    LinkedList<String> gfg = new LinkedList<String>();

    // Adding values
    gfg.add("GEEKS");
    gfg.add("FOR");
    gfg.add("GEEKS");

    System.out.println("LinkedList Elements : ");

    for (int i = 0; i < gfg.size(); i++) {

        // get(i) returns element present at index i
        System.out.println("Element at index " + i
                           + " is: " + gfg.get(i));
    }
}

}

`

Output

LinkedList Elements : Element at index 0 is: GEEKS Element at index 1 is: FOR Element at index 2 is: GEEKS

2. We can use the iterator() method

• To use this method we have to import java.util.Iterator package.
• In this method, we can iterate over the LinkedList and then extract the element at the given index accordingly. Java `

// Java program to iterate over linkedlist // to extract elements of linkedlist

import java.io.*; import java.util.LinkedList; import java.util.Iterator; class GFG { public static void main(String[] args) {

    LinkedList<String> gfg = new LinkedList<String>();

    // Adding elements
    gfg.add("GEEKS");
    gfg.add("FOR");
    gfg.add("GEEKS");

    // Create an object of Iterator
    Iterator<String> i = gfg.iterator();

    System.out.print(
        "The elements of the input LinkedList: \n");

    int j = 0;

    // has.next() returns true if there is a next
    // element
    while (i.hasNext()) {

        System.out.print("The element at the index " + j
                         + " ");

        // next() returns the next element
        String str = i.next();

        System.out.print(str);
        System.out.print(" \n");

        ++j;
    }
}

}

`

Output

The elements of the input LinkedList: The element at the index 0 GEEKS The element at the index 1 FOR The element at the index 2 GEEKS

3. We can use ListIterator() method**.**

• ListIterator() is a subinterface of Iterator() method.
• It provides us with the function to access the elements of a list.
• It is bidirectional that means it allows us to iterate elements of a list in the both the direction.
• To use this method we have to import java.util.ListIterator. Java `

// Java program to iterate over the // linkedlist using listIterator()

import java.io.*; import java.util.LinkedList; import java.util.ListIterator;

class GFG { public static void main(String[] args) {

    LinkedList<String> gfg = new LinkedList<String>();

    // Adding elements
    gfg.add("GEEKS");
    gfg.add("FOR");
    gfg.add("GEEKS");

    // Create an object of ListIterator
    ListIterator<String> li = gfg.listIterator();

    System.out.print(
        "The elements of the LinkedList: \n");

    // hasNext() returns true if there is next element
    int j = 0;

    while (li.hasNext()) {

        // next() returns the next element
        System.out.print("The element at the index " + j
                         + " ");

        System.out.print(li.next());

        System.out.print("\n");

        ++j;
    }
    --j;

    // Now to show that ListIterator() can traverse in
    // both the direction
    System.out.print(
        "\nThe elements of the LinkedList in Reverse order: \n");

    // hasprevious() checks if there is a previous
    // element
    while (li.hasPrevious()) {

        System.out.print("The element at the index " + j
                         + " ");

        // previous() returns the previous element
        System.out.print(li.previous());
        System.out.print("\n");

        --j;
    }
}

}

`

Output

The elements of the LinkedList: The element at the index 0 GEEKS The element at the index 1 FOR The element at the index 2 GEEKS

The elements of the LinkedList in Reverse order: The element at the index 2 GEEKS The element at the index 1 FOR The element at the index 0 GEEKS