enhancement: #1947 implement chain of responsibilities with java stream (#2123)

chain-of-responsibility/etc/chain-of-responsibility.urm.puml

@@ -5,25 +5,34 @@ package com.iluwatar.chain {
     + main(args : String[]) {static}
   }
   class OrcCommander {
-    + OrcCommander(handler : RequestHandler)
-    + handleRequest(req : Request)
-    + toString() : String
+    - LOGGER : Logger {static}
+    + OrcCommander()
+    + canHandleRequest(req : Request) : boolean
+    + getPriority() : int
+    + handle(req : Request)
+    + name() : String
   }
   class OrcKing {
-    - chain : RequestHandler
+    - handlers : List<RequestHandler>
     + OrcKing()
     - buildChain()
     + makeRequest(req : Request)
   }
   class OrcOfficer {
-    + OrcOfficer(handler : RequestHandler)
-    + handleRequest(req : Request)
-    + toString() : String
+    - LOGGER : Logger {static}
+    + OrcOfficer()
+    + canHandleRequest(req : Request) : boolean
+    + getPriority() : int
+    + handle(req : Request)
+    + name() : String
   }
   class OrcSoldier {
-    + OrcSoldier(handler : RequestHandler)
-    + handleRequest(req : Request)
-    + toString() : String
+    - LOGGER : Logger {static}
+    + OrcSoldier()
+    + canHandleRequest(req : Request) : boolean
+    + getPriority() : int
+    + handle(req : Request)
+    + name() : String
   }
   class Request {
     - handled : boolean
@@ -36,13 +45,11 @@ package com.iluwatar.chain {
     + markHandled()
     + toString() : String
   }
-  abstract class RequestHandler {
-    - LOGGER : Logger {static}
-    - next : RequestHandler
-    + RequestHandler(next : RequestHandler)
-    + handleRequest(req : Request)
-    # printHandling(req : Request)
-    + toString() : String {abstract}
+  interface RequestHandler {
+    + canHandleRequest(Request) : boolean {abstract}
+    + getPriority() : int {abstract}
+    + handle(Request) {abstract}
+    + name() : String {abstract}
   }
   enum RequestType {
     + COLLECT_TAX {static}
@@ -52,10 +59,9 @@ package com.iluwatar.chain {
     + values() : RequestType[] {static}
   }
 }
-OrcKing -->  "-chain" RequestHandler
-RequestHandler -->  "-next" RequestHandler
+OrcKing -->  "-handlers" RequestHandler
 Request -->  "-requestType" RequestType
-OrcCommander --|> RequestHandler 
-OrcOfficer --|> RequestHandler 
-OrcSoldier --|> RequestHandler 
+OrcCommander ..|> RequestHandler 
+OrcOfficer ..|> RequestHandler 
+OrcSoldier ..|> RequestHandler 
 @enduml