Command (org.refcodes:refcodes-command 2.0.0 API)

Type Parameters:

CTX - The context type to use, can by any Component, service or POJO.

RET - The return type of the Command's proceedings.

E - The exception type of the Command's erroneous termination.

All Known Subinterfaces:

Undoable<CTX,RET,E>

All Known Implementing Classes:

AbstractCommand, AbstractUndoable

Functional Interface:

This is a functional interface and can therefore be used as the assignment target for a lambda expression or method reference.
```
@FunctionalInterface
public interface Command<CTX,RET,E extends java.lang.Exception>
```
A Command (Command) represents an (atomic) operation applied to a context returning a result encapsulated in an object (as of object oriented programming). An Undoable is a command which provides means to undo its operation applied before. The Command is created by a client (e.g. the business logic) and passed to something like a command-bus or command-processor for execution.

Method Summary

All Methods Instance Methods Abstract Methods
Modifier and Type	Method	Description
`RET`	`execute(CTX aContext)`	The invoker executes a `Command` by providing it a context (being a service, a `Component` or a POJO).

- Method Detail
  - execute
```
RET execute(CTX aContext)
     throws E extends java.lang.Exception
```
    The invoker executes a Command by providing it a context (being a service, a Component or a POJO). The method works synchronously and waits (blocks the caller's thread) till a result is available.
    
    Parameters:
    
    aContext - The target object (being a service, a Component or a POJO) which is used by the Command to perform its (atomic) operation.
    
    Returns:
    
    The result of this Command after execution or Void in case this Command does not process a result.
    
    Throws:
    
    E - the e
    
    E extends java.lang.Exception