How to get the first element of List in Java?

The List interface extends the Collection interface. It is a collection that stores a sequence of elements. ArrayList is the most popular implementation of the List interface. Users of lists have very precise control over where elements are inserted into the list. These elements are accessible through their index and are searchable.

The List interface provides the get() method to get the element at a specific index. You can specify index as 0 to get the first element of the List. In this article, we will explore the usage of get() method through several examples.

Syntax

E get(int index)

Returns the element at the specified position.

Parameters

• index - The index of the element returned.

Returns the element at the specified position

.

Throws

• IndexOutOfBoundsException - if the index is out of range (index < 0 || index >= size())

Example 1

The following example shows how to get the first element from a list.

package com.tutorialspoint;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;

public class CollectionsDemo {
   public static void main(String[] args) {
      List<Integer> list = new ArrayList<>(Arrays.asList(4,5,6));
      System.out.println("List: " + list);

      // First element of the List
      System.out.println("First element of the List: " + list.get(0));

   }
}

Output

This will produce the following result-

List: [4, 5, 6]
First element of the List: 4

Example 2

In the following example, getting the first element from the List may throw abnormal.

package com.tutorialspoint;
import java.util.ArrayList;
import java.util.List;

public class CollectionsDemo {
   public static void main(String[] args) {
      List<Integer> list = new ArrayList<>();
      System.out.println("List: " + list);
     
      try {
         // First element of the List
         System.out.println("First element of the List: " + list.get(0));
      } catch(Exception e) {
         e.printStackTrace();
      }
   }
}

Output

This will produce the following results -

List: []
java.lang.IndexOutOfBoundsException: Index: 0, Size: 0
   at java.util.ArrayList.rangeCheck(ArrayList.java:659)
   at java.util.ArrayList.get(ArrayList.java:435)
   at com.tutorialspoint.CollectionsDemo.main(CollectionsDemo.java:11)

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