Concurrency, reflection and Factory pattern
- From: "Maciej" <mgawinecki@xxxxxxxxx>
- Date: 28 Nov 2006 06:24:13 -0800
Hi everyone,
Here is my problem:
Case:
- server application which launches concurrently tasks (precisely
classes extending class Task)
- new types of task can be registered at the server by the developer
- only class of task which matches incoming request, is launched
Proposed solution:
- Developer registers not instances of tasks, but their classes in the
server
- If static method matches() of one task's class returns true, then
this class is instancianized by use of Java reflection
Pros:
1. no instance of Task class is necessary to check its matching
condition
2. both: matching condition and related solve() method are defined in a
single class
Cons:
1. this approach is easy to abuse, since static methods cannot be
abstract and or overriden, which does not force developer to implement
them in classes which derive from Task class.
I was wondering about using Factory pattern, which creates instances of
class, but this forces me to break 2nd advantage. Do you see any other
solution ?
TIA,
Maciej
ps. Here is example of Task class
public abstract class Task<R,T> {
private R request;
/* This method must be implemented in deriving class */
public abstract T solve();
/* This method method must be over-hidden in deriving class. */
public static boolean matches(R request) {
return false;
}
public Task(R request) {
this.request = request;
}
.
- Prev by Date: Send messages on Multicast Group from different subnets
- Next by Date: Thread + stack + synchronization.
- Previous by thread: Send messages on Multicast Group from different subnets
- Next by thread: Thread + stack + synchronization.
- Index(es):
Relevant Pages
|
