[Webinar] Learn how to a build a cloud-first strategyRegister Now

x
  • Status: Solved
  • Priority: Medium
  • Security: Public
  • Views: 14109
  • Last Modified:

Difference between loosely coupled and tightly coupled.

What is difference between Loosely coupled and tightly coupled application.This is in context of JMS(Java Message Service)like example.:-

"Messaging enables distributed communication that is loosely coupled and messaging differs from tightly coupled technologies such as Remote Method Invocation "

What exactly above quotes mean.
0
deepakad
Asked:
deepakad
1 Solution
 
Prasanna_HebbarCommented:
Loosely coupled applications : Each of the applications can be modified independently. Easy for maintainance. For example, if you are using xml for data transfer between two applications, in future you can add two more tags to your xml. So one application(server) can change, not requiring the other application(client) to change.

But in case of tightly coupled applications, ie RMI. the method signature is defined. Eg:
process(String firstName, String lastName);
Suppose tomorrow if you want to change the signature, say add one more parameter.
process(String firstName, String lastName, String middleInitial);

Then the server application and the client application has to be changed simultaneously.

So changing one application requires the changes to other applications in tightly coupled applications. Whereas this is mostly not required in loosely coupled applications.
0
 
JonathanJonasCommented:
The following is a definition from http://www.techweb.com/encyclopedia/ It refers to coupling in hardware, but is useful anyway.

tightly coupled

 
Refers to two or more computers linked together and dependent on each other. One computer may control the other, or both computers may monitor each other. For example, a database machine is tightly coupled to the main processor. Two computers tied together for multiprocessing are tightly coupled. Contrast with loosely coupled, such as personal computers in a LAN.
 

In terms of application software, the meaning is similar - an app or component which is tightly coupled depends on another app or component and if the other app has changed it will not function properly. Tight coupling is a Bad Thing. Loose coupling is desirable, it enables an app to change the way it works internally without affecting other components which use it.

JMS is loosely coupled because it allows disparate systems to subscribe to a queue or topic unlike RMI which directly uses the objects that it needs.

Cheers,

Jonathan
 
0
 
deepakadAuthor Commented:
Hi Prasana,

Is this is the case will be true in JMS also.

If yes then i can accept your answer.
0
 
sudhakar_koundinyaCommented:
No comment has been added lately, so it's time to clean up this TA.
I will leave a recommendation in the Cleanup topic area that this question is:


[Points to Prasanna_Hebbar]


Please leave any comments here within the next seven days.
 
PLEASE DO NOT ACCEPT THIS COMMENT AS AN ANSWER!
 
sudhakar_koundinya
EE Cleanup Volunteer
---------------------
If you feel that your question was not properly addressed, or that none of the comments received were appropriate answers, please post your concern in THIS thread.
0

Featured Post

What does it mean to be "Always On"?

Is your cloud always on? With an Always On cloud you won't have to worry about downtime for maintenance or software application code updates, ensuring that your bottom line isn't affected.

Tackle projects and never again get stuck behind a technical roadblock.
Join Now