Iterate list in java 8

Lists in Java allow us to maintain an ordered collection of objects. Duplicate elements as well as null elements can also be stored in a List in Java.

The List interface is a part of java.util package and it inherits the Collection interface.

How to iterate list of objects in java

It preserves the order of insertion.

There are several ways to iterate over List in Java. They are discussed below:

Methods:

1. Using loops (Naive Approach)
2. Using Iterator
3. Using List iterator
4. Using lambda expression
5. Using stream.forEach()
6. Using Spliterator (Java 8 and later)

Method 1-A: Simple for loop

Each element can be accessed by iteration using a simple for loop.

The index can be accessed using the index as a loop variable.

Syntax:

for (i = 0; i < list_name.size(); i++) { // code block to be executed }

Below is an example of this method:

Complexity of the above Method:

Time Complexity: O(n), where ‘n’ is the size of the list.
Auxiliary Space: O(1), Constant space is used for loop variables (i in this case).

Method 1-B: Enhanced for loop

Each elem

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