What is the difference between loose coupling and

Question

Can any one describe the exact difference between loose coupling and tight coupling in Object oriented paradigm?

Answer 1

The way I understand it is, that tightly coupled architecture does not provide a lot of flexibility for change when compared to loosely coupled architecture.

But in case of loosely coupled architectures, message formats or operating platforms or revamping the business logic does not impact the other end. If the system is taken down for a revamp, of course the other end will not be able to access the service for a while but other than that, the unchanged end can resume message exchange as it was before the revamp.

Answer 2

Loose coupling means that the degree of dependency between two components is very low.
Example: GSM SIM

Tight coupling means that the degree of dependency between two components is very high.
Example: CDMA Mobile

Answer 3

It's about classes dependency rate to another ones which is so low in loosely coupled and so high in tightly coupled. To be clear in the service orientation architecture, services are loosely coupled to each other against monolithic which classes dependency to each other is on purpose

Answer 4

In object oriented design, the amount of coupling refers to how much the design of one class depends on the design of another class. In other words, how often do changes in class A force related changes in class B? Tight coupling means the two classes often change together, loose coupling means they are mostly independent. In general, loose coupling is recommended because it's easier to test and maintain.

You may find this paper by Martin Fowler (PDF) helpful.

Answer 5

When two objects are loosely coupled, they can interact but have very little knowledge of each other.

Loosely coupled designs allow us to build flexible OO systems that can handle change.

Observer design pattern is a good example for making classes loosely coupled, you can have a look on it in Wikipedia.

Answer 6

There are certain tools that provide dependency injection through their library, for example in .net we have ninject Library .

If you are going further in java then spring provides this capabilities.

Loosly coupled objects can be made by introducing Interfaces in your code, thats what these sources do.

Say in your code you are writing

Myclass m = new Myclass();

now this statement in your method says that you are dependent on myclass this is called a tightly coupled. Now you provide some constructor injection , or property injection and instantiating object then it will become loosly coupled.