Java get last element in array

How to Access Last Element of Array In Java

How to Access Last Element of Array In Java? In this post, we will discuss how to access last element of array In Java. To do this we can use the inbuilt “length” property defined for the array in the Java programming example. Also see:- Find Length of Array in Java

Let us see some examples of last element of an array In Java:-

1) Array = [1,6,8,5,36]The last element is 36

2) Array = [6,7,8,0]The last element is 0

3) Array = [4,5,-9]The last element is -9

Program to Access Last Element of Array In Java

Step-1:- Import the necessary classes.
Step-2:- Create a class with the main method and the method required to retrieve the last element.

Step-3:- Instantiate the scanner class and take the inputs from the user by using for loop read the elements of the array.
Step-4:- Print the array elements by Arrays.toString() method, this method converts the array elements to string elements.

Step-5:- Print the last element using lastElement() method.
Step-6:- The lastElement() method takes an array as a parameter if the length of an array is 0 it says “Array is Empty” or else it returns the last element.

Demonstration of How to Access Last Element of Array In Java

import java.util.Scanner; import java.util.Arrays; public class Main < public static void main(String arg[]) < Scanner scan = new Scanner(System.in); System.out.print("Enter the number of "+ "elements in the array: "); int n = scan.nextInt(); int arr[] = new int[n]; System.out.println("Enter " + n + " array elements: "); for (int i = 0; i < n; i++) < arr[i] = scan.nextInt(); >System.out.println("Array = " + Arrays.toString(arr)); System.out.println("The last element of an array is = " + lastElement(arr)); scan.close(); > public static int lastElement(int arr[]) < if (arr.length == 0) < System.out.println("Array is Empty"); return 0; >return arr[arr.length - 1]; > >

Enter the number of elements in the array: 5
Enter 5 array elements:
30 40 15 20 25
Array = [30, 40, 15, 20, 25]The last element of the array is = 25

Enter the number of elements in the array: 7
Enter 7 array elements:
9 18 27 36 45 54 63
Array = [9, 18, 27, 36, 45, 54, 63]The last element of the array is = 63

Test case where the array is empty

Enter the number of elements in the array: 0
Enter 0 array elements:
Array = [ ]Array is Empty
The last element of an array is = 0

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How to Get the Last Element of Array or ArrayList in Java: Step-by-Step Guide and Best Practices

Learn how to get the last element of an array or ArrayList in Java with our step-by-step guide. Find out the best practices, methods, and tips for efficient coding.

If you are a Java developer, you may have encountered the problem of retrieving the last element of an array or ArrayList. This task may seem simple, but it can be challenging if you are not familiar with the different methods and best practices involved.

In this post, we will provide you with a step-by-step guide on how to get the last element of an array or ArrayList in Java. We will cover various methods, best practices, and tips and tricks for efficient coding.

How to Get the Last Element of an Array in Java?

Arrays are fixed in size, and their elements can be accessed using index numbers. To get the last element of an array in Java, you can use the following methods:

Method 1: Using Index Numbers

To access the last element of an array, you can use the index number of the last element, which is the size of the array minus one. Here’s an example:

int[] numbers = ; int lastElement = numbers[numbers.length-1]; System.out.println(lastElement); // Output: 5 

Method 2: Using the length Method

Java’s arrayname.length method can be used to find the last element of an array. Here’s an example:

int[] numbers = ; int lastElement = numbers[numbers.length]; System.out.println(lastElement); // Output: ArrayIndexOutOfBoundsException 

However, you need to check the validity of the index before using it to avoid an ArrayIndexOutOfBoundsException. Here’s an example:

int[] numbers = ; if (numbers.length > 0) < int lastElement = numbers[numbers.length-1]; System.out.println(lastElement); // Output: 5 >

Method 3: Using Arrays.copyOf() Method

You can also use the Arrays.copyOf() method to remove the last element of an array and get the last element. Here’s an example:

int[] numbers = ; int lastElement = Arrays.copyOf(numbers, numbers.length)[numbers.length-1]; System.out.println(lastElement); // Output: 5 

How to Get the Last Element of an ArrayList in Java?

ArrayLists can grow dynamically, and their size can be obtained using the size() method. To get the last element of an arraylist in java, you can use the following methods:

Method 1: Using the get() Method

You can use the get() method and pass in the index size-1 to get the last element of an ArrayList. Here’s an example:

ArrayList numbers = new ArrayList(Arrays.asList(1, 2, 3, 4, 5)); int lastElement = numbers.get(numbers.size()-1); System.out.println(lastElement); // Output: 5 

Method 2: Using the size() Method

You can also use the size() method to find the size of the ArrayList and then use the get() method to get the last element. Here’s an example:

ArrayList numbers = new ArrayList(Arrays.asList(1, 2, 3, 4, 5)); if (numbers.size() > 0) < int lastElement = numbers.get(numbers.size()-1); System.out.println(lastElement); // Output: 5 >

Method 3: Using Reverse Iterator

You can use a Reverse Iterator to get the last item of a list. Here’s an example:

ArrayList numbers = new ArrayList(Arrays.asList(1, 2, 3, 4, 5)); if (numbers.size() > 0) < ListIteratoriterator = numbers.listIterator(numbers.size()); int lastElement = iterator.previous(); System.out.println(lastElement); // Output: 5 > 

Finding the First and Last Elements of an Array in Java using Java 8 Streams API

java 8 streams api provides a concise and expressive way to manipulate collections. To find the first and last elements of an array using Java 8 Streams API, you can use the following methods:

Method 1: Using the Stream.of() Method

You can use the Stream.of() method to create a stream of elements in an array. Here’s an example:

int[] numbers = ; int firstElement = Stream.of(numbers).findFirst().getAsInt(); int lastElement = Stream.of(numbers).reduce((a, b) -> b).getAsInt(); System.out.println(firstElement); // Output: 1 System.out.println(lastElement); // Output: 5 

Method 2: Using the min() and max() Methods

You can also use the min() and max() methods to find the first and last elements of an array. Here’s an example:

int[] numbers = ; int firstElement = Arrays.stream(numbers).min().getAsInt(); int lastElement = Arrays.stream(numbers).max().getAsInt(); System.out.println(firstElement); // Output: 1 System.out.println(lastElement); // Output: 5 

Finding the Index of the Last Occurrence of an Element in an ArrayList

To find the index of the last occurrence of an element in an ArrayList, you can use the lastIndexOf() method. Here’s an example:

ArrayList numbers = new ArrayList(Arrays.asList(1, 2, 3, 4, 5, 3)); int lastIndexOfThree = numbers.lastIndexOf(3); System.out.println(lastIndexOfThree); // Output: 5 

The method returns the last index at which a given element can be found in the ArrayList, or -1 if it is not present. If you want to get the last element of a collection, you can use toArray() and then return the last element of the array.

Differences between Array and ArrayList

Arrays and ArrayLists have some differences in terms of size, data types, and speed. Here are some of the main differences:

• Arrays are fixed in size, whereas ArrayLists can grow dynamically.
• Arrays can store only homogeneous data types, whereas ArrayLists can store any data type.
• Arrays are faster than ArrayLists for accessing and manipulating elements, whereas ArrayLists are slower.

Other helpful code samples for getting the last element of an array in Java

In Java case in point, java last element in array code example

 arrayName[arrayName.length() - 1];

In Java , for example, get last element of array java code example

firstNum = numbers[0]; lastNum = numbers[numbers.length-1];

In Java , for instance, how to get the last element of array in java code example

int[] arr = new int[5]; //length of the array is 5 int val = arr[arr.length - 1]; //here variable val stores the last element of arr

In Java , for instance, java find last element in array code example

int [] numbers = ;firstElement = numbers[0]; lastElement = numbers[numbers.length-1];

In Java as proof, how to get last element of array java code example

int last = list.get(list.size() - 1); 

In Java case in point, find last element in array in java code sample

firstNum = numbers.get(0); lastNum = numbers.get(numbers.size() - 1); 

In Java , for example, get last element of array java code example

int a[]=; int last = a[a.length-1];

In Java , how to find last element in array java code sample

// GIVE FIRST NUMBER AND LAST NUMBER firstNum = numbers[0]; lastNum = numbers[numbers.length-1];

Conclusion

In conclusion, getting the last element of an array or ArrayList in Java can be achieved using various methods and best practices. By following the steps outlined in this post, developers can easily and efficiently retrieve the last element of an array or ArrayList in Java. Always make sure to check the validity of the index and choose the method that best fits your needs.

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How to get first and last element in an array in java?

Java provides multiple ways to access the first and last elements of an array. Here are a few examples of how to accomplish this:

Method 1: Using Array Index

This is because in Java, arrays are zero-indexed, which means the first element of an array is at index 0, the second element is at index 1, and so on.

So, to get the first element of the array, you can use the following code: int firstElement = numbers[0];

This is because the last element of an array is at an index that is one less than the length of the array.

So, to get the last element of the array, you can use the following code: int lastElement = numbers[numbers.length — 1];

Method 2: Using ArrayList

For example, ArrayList numbers = new ArrayList();

For example, numbers.add(1); numbers.add(2); numbers.add(3); numbers.add(4); numbers.add(5);

int firstElement = numbers.get(0);

int lastElement = numbers.get(numbers.size() — 1);

Method 3: Using for loop

For example, int firstElement = numbers[0];

In the for loop, check if the current element is the first element. If yes, then assign the current element to the first element variable.

For example, int lastElement = numbers[0];

In the for loop, check if the current element is the last element. If yes, then assign the current element to the last element variable.

In the above examples, we have used int[] array, but you can use the same logic for other data types like String, Double, etc.

One important thing to note is that, if the array is empty, accessing the first and last element will result in an ArrayIndexOutOfBoundsException. So, it is always a good practice to check if the array is empty or not before accessing its elements.

Sure, here are a few more examples to further illustrate how to access the first and last elements of an array in Java:

Method 4: Using for-each loop

For example, int firstElement = numbers[0];

In the for-each loop, check if the current element is the first element. If yes, then assign the current element to the first element variable.

For example, int lastElement = numbers[0];

In the for-each loop, check if the current element is the last element. If yes, then assign the current element to the last element variable.

Method 5: Using Stream API

For example, IntStream stream = Arrays.stream(numbers);

For example, int firstElement = stream.findFirst().getAsInt();

For example, int lastElement = stream.skip(numbers.length — 1).findAny().getAsInt();

In the above examples, we have used int[] array, but you can use the same logic for other data types like String, Double, etc.

Conclusion

In conclusion, accessing the first and last elements of an array in Java is a fundamental task that can be done in multiple ways. We have discussed several methods such as using array index, ArrayList, for loop, for-each loop, and Stream API. Each method has its own advantages and disadvantages and should be chosen based on the specific requirements of the task at hand. Additionally, it’s crucial to always check if the array is empty before accessing its elements to prevent ArrayIndexOutOfBoundsException. Understanding these methods and how to use them correctly is essential for any Java developer, especially beginners.

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