Learn Java Programming - Aggregation Tutorial

I highly recommend watching my Composition Tutorial prior to watching this one. We learned that an object demonstrating composition is composed of other objects that are created inside of the object during instantiation. The lifetime of those "internal" objects are entirely dependent upon the enclosing object. When the instance of the enclosing object is destroyed, those "internal" objects are destroyed as well. Aggregation is very similar to composition only with one key difference. An object demonstrating aggregation is composed of other objects that are created outside of the object during instantiation. In aggregation, the lifetime of those "internal" objects are not dependent upon the enclosing object. When the instance of the enclosing object is destroyed, those "internal" objects are still alive because they were created elsewhere. Consider the following code that demonstrates aggregation...