Collection is one of the most important topics for Java programming. Without the proper knowledge of every collection type in Java, it becomes difficult for you to decide which option to pick in a particular scenario.

This course will give you a great understanding of all collection types available in the Collections Framework like lists, linked lists, sets, and hashmaps. 

After completing this course, you will know how data can be modified within a collection, how to sort a collection, and how it can be made thread-safe. You will also cover the internal working of each Java collection so you can work with them more efficiently.

Collections in Java

## Problem 1: Find employees aged over 50

All the employee names whose age is more than 50.

### Solution:

We can iterate the ArrayList using a `for` loop or an enhanced `for` loop. For each element, we can check that if age is greater than 50, then print the name of the employee.

>This can be done easily using streams in Java 8. We will share that solution as well. If you are not familiar with these Java 8 features, then you can use the classic approach.

# Problem 1: Find employees aged over 50

All the employee names whose age is more than 50.

## Solution:

We can iterate the ArrayList using a `for` loop or an enhanced `for` loop. For each element, we can check that if age is greater than 50, then print the name of the employee.

>This can be done easily using streams in Java 8. We will share that solution as well. If you are not familiar with these Java 8 features, then you can use the classic approach.

Let's look at the solutions for the ArrayList practice problems.

Let's Begin

Lists in Java

LinkedList in Java

CopyOnWriteArrayList in Java

Sets in Java

TreeSet in Java

HashMap In Java

TreeMap in Java

LinkedHashMap in Java

Additional Map Implementations

Arrays Class

Collections Class

ArrayList: Exercise Solution

Problem 1: Find employees aged over 50

Solution: