Java Interfaces Methodology: Should every class implement an interface?

Posted by Amir Rachum on Stack Overflow See other posts from Stack Overflow or by Amir Rachum
Published on 2010-04-17T17:41:29Z Indexed on 2010/04/17 18:23 UTC
Read the original article Hit count: 185

Filed under:

java

|

interfaces

|

best-practices

I've been programming in Java for a few courses in the University and I have the following question:

Is it methodologically accepted that every class should implement an interface? Is it considered bad practice not to do so? Can you describe a situation where it's not a good idea to use interfaces?

Edit: Personally, I like the notion of using Interfaces for everything as a methodology and habit, even if it's not clearly beneficial. Eclipse automatically created a class file with all the methods, so it doesn't waste any time anyway.

© Stack Overflow or respective owner

Related posts about java

Tomcat 6: Access Control Exception?

as seen on Server Fault - Search for 'Server Fault'
I'm trying to setup a tomcat6 server, and I'm trying to match another setup someone else established. However, my deployment (default Ubuntu install) uses a policy.d/ directory structure, and the established server just uses a catalina.policy file. I've tried setting every entry in policy.d to match… >>> More
Problem in creation MDB Queue connection at Jboss StartUp

as seen on Stack Overflow - Search for 'Stack Overflow'
I am not able to create a Queue connection in JBOSS4.2.3GA Version & Java1.5, as I am using MDB as per the below details. I am putting this MDB in a jar file(named utsJar.jar) and copied it in deploy folder of JBOSS, In the test env. this MDB works well but in another env. [ env settings and… >>> More
failing to establish connection between Postgres db and gwt

as seen on Stack Overflow - Search for 'Stack Overflow'
Hi, I am using Postgres and gwt 2.0 for one of my applications. I am facing problem connecting to the database. When I try to connect it gives "ClassNotFoundException". Here is what I get when I try to connect to database: java.lang.ClassNotFoundException: org.postgresql.Driver at java.net… >>> More
failing to establish connection between postgre db and gwt

as seen on Stack Overflow - Search for 'Stack Overflow'
Hi, For i am using postgre and gwt 2.0 for one of my applications. I am facing problem connecting to the database. When i try to connect it gives "ClassNotFoundException". Here is what i get when i try to connect to database: java.lang.ClassNotFoundException: org.postgresql.Driver at java.net… >>> More
Migration and deployement problems JBoss 4.2.2.GA to JBoss 6.0.0.M2

as seen on Stack Overflow - Search for 'Stack Overflow'
Hi, I'm trying to migrate an application running on JBoss 4.2.2.GA to JBoss 6.0.0.M2 I give you some log to explain my problem : boot.log : 2010-03-16 09:59:29,406 ERROR [org.jboss.system.server.profileservice.ProfileServiceBootstrap] (Thread-2) Failed to load profile: Summary of incomplete deployments… >>> More

Related posts about interfaces

Should interfaces inherit interfaces

as seen on Programmers - Search for 'Programmers'
Although this is a general question it is also specific to a problem I am currently experiencing. I currently have an interface specified in my solution called public interface IContextProvider { IDataContext { get; set; } IAreaContext { get; set; } } This interface is often used throughout… >>> More
Should interfaces extend (and in doing so inherit methods of) other interfaces

as seen on Programmers - Search for 'Programmers'
Although this is a general question it is also specific to a problem I am currently experiencing. I currently have an interface specified in my solution called public interface IContextProvider { IDataContext { get; set; } IAreaContext { get; set; } } This interface is often used throughout… >>> More
What problems will I face if I remove the concept of interfaces from my code?

as seen on Programmers - Search for 'Programmers'
I have been programming for many years but I am still not comfortable with the concept of "Interfaces". I try to use interfaces but many times I don't see a mandatory use for it. I think this is probably because the projects weren't so big, or because interfaces are more useful when teamwork is involved… >>> More
Explicit C# interface implementation of interfaces that inherit from other interfaces

as seen on Stack Overflow - Search for 'Stack Overflow'
Consider the following three interfaces: interface IBaseInterface { event EventHandler SomeEvent; } interface IInterface1 : IBaseInterface { ... } interface IInterface 2 : IBaseInterface { ... } Now consider the following class that implements both IInterface1 and IInterface 2: class… >>> More
How to force multiple Interfaces to include certain the same properties?

as seen on Stack Overflow - Search for 'Stack Overflow'
I am trying to figure out a way to force all of my Interfaces to include properties of the same name/type. For example: I have two Interfaces; IGetAlarms and IGetDiagnostics. Each of the Interfaces will contain properties that are specific to the Interface itself, however I want to force the two… >>> More