All Questions
24 questions
1vote
1answer
234views
Refactoring instanceOf, moving logic to POJO when it has database interaction
I'm refactoring some old code, I have a lot of istanceOf in the business part: if (record instanceof RecordA) { RecordA recordA = (RecordA) record; ...
- 200
2votes
1answer
204views
Is it allowed to include the composition in the compositor in the Strategy Pattern
I have a range of different animals in my zoo such as turtles, birds etc. As they all share a common trait such as either swimming, flying etc., I thought a strategy pattern would be appropriate to ...
- 2,492
0votes
6answers
247views
Adding client specific method to a listener interface is a good idea?
I'm using a listener pattern where a class A listens for events from various classes B, C, D with the help of a listener interface I Essentially the structure looks like: interface I { void ...
- 3,085
152votes
6answers
118kviews
What is the point of having every service class have an interface? [duplicate]
At the company I work at, every service class has a corresponding interface. Is this necessary? Notes: Most of these interfaces are only used by a single class We are not creating any sort of ...
- 109
3votes
1answer
4kviews
Should an abstract class implement an interface, as opposed to defining its own abstract methods?
I'm defining a class structure for persisting to our cassandra database, and I'm unsure about using a combination of an abstract class and an interface. I have two concrete classes, one for persisting ...
3votes
5answers
2kviews
Explanation of the definition of interface inheritance as described in GoF book
I am reading the first chapter of the Gof book. Section 1.6 discusses about class vs interface inheritance: Class versus Interface Inheritance It's important to understand the difference between an ...
- 121
0votes
3answers
368views
Send records using async or sync way
I have bunch of keys and values that I want to send to our messaging queue by packing them in one byte array. I will make one byte array of all the keys and values which should always be less than 50K ...
- 137
2votes
5answers
1kviews
Facade pattern or just expose child objects?
Wondering about pros and cons around a facade pattern implementation (or perhaps there is a better pattern I should consider), versus simply exposing a dependent object to a caller. Consider the ...
CommunityBot
- 1
1vote
2answers
328views
Is this one method interface a good response to this interview question?
Today I received a rejection letter from a company where as part of the interview process they gave a a couple days to respond to the following question (paraphrased): Let’s say say you have ...
CommunityBot
- 1
3votes
1answer
540views
Contract interface/class with inner classes/interfaces
Brief description of my project structure. I have some base classes like BaseView, BasePresenter ... . Also my project consists of modules, module represents one complete part of the application. ...
- 1,899
9votes
4answers
5kviews
How to force "program to an interface" without using a java Interface in java 1.6
In java 1.8 they have wonderful new "default interface methods". In 1.6 how close can we come? The goal: use code to keep clients from being able to tell that a class is not a java interface. If we ...
CommunityBot
- 1
3votes
1answer
184views
Leo Brodie's "Interface Component"
On page 85 of Leo Brodie's book, Thinking Forth, he describes a component which he calls the "Interface Component." He describes its differences from, and benefits over a standard interface ...
CommunityBot
- 1
3votes
3answers
2kviews
Preemptive interfaces in Java - good, bad or "a matter of taste"
I frequently come across projects that strictly define an interface for each and every class. 90% of those interfaces feature only a single implementation. Proponents of these "preemptive interfacs" ...
- 39.6k
3votes
4answers
6kviews
Implements > extends, but what about variables?
It's preferable to write programs that depend on interfaces rather than on superclasses, but what if you want a class to have certain variables? Sometimes you want a class to implement a certain ...
CommunityBot
- 1
4votes
3answers
6kviews
Communicating to an Object from another without coupling in java?
So I have a Person object, and a GumballMachine object. The behavior I'm searching for is, in the intent to avoid unnecessary coupling, have the method insertCoin() called from within the Person ...
CommunityBot
- 1
