When to use Composite Design Pattern?
Composite Pattern should be used when clients need to ignore the difference between compositions of objects and individual objects. If programmers find that they are using multiple objects in the same way, and often have nearly identical code to handle each of them, then composite is a good choice, it is less complex in this situation to treat primitives and composites as homogeneous.
- Less number of objects reduces the memory usage, and it manages to keep us away from errors related to memory like java.lang.OutOfMemoryError.
- Although creating an object in Java is really fast, we can still reduce the execution time of our program by sharing objects.
Composite Design Pattern in Java
The Composite Design Pattern is a structural design pattern that lets you compose objects into tree-like structures to represent part-whole hierarchies. It allows clients to treat individual objects and compositions of objects uniformly. In other words, whether dealing with a single object or a group of objects (composite), clients can use them interchangeably.
As described by the Gang of four, “Compose objects into tree structure to represent part-whole hierarchies. Composite lets client treat individual objects and compositions of objects uniformly”.
The key concept is that you can manipulate a single instance of the object just as you would manipulate a group of them. The operations you can perform on all the composite objects often have the least common denominator relationship.
Important Topics for the Composite Design Pattern in Java
- Components of Composite Design Pattern
- Composite Design Pattern example in Java
- Why do we need Composite Design Pattern?
- When to use Composite Design Pattern?
- When not to use Composite Design Pattern?