composite

Composite

Composite Pattern structures components into a tree structure and treat each node and leaf uniformly.

Code

Employee is an interface implemented by Engineer and Manager. Manager has multiple direct reports where each report is an Employee - a Engineer or another Manager. So, we build a tree structure here - Manager is a node (or a leaf if he/she doesn't have any direct report), and Engineer is a leaf.

Reference

• https://en.wikipedia.org/wiki/Composite_pattern
• https://dzone.com/articles/composite-design-pattern-in-java-1