Java 11 migrate remaining e (#1112)

* Moves eip-aggregator to Java 11

* Moves eip-message-channel to Java 11

* Moves eip-publish-subscribe to Java 11

* Moves eip-splitter to Java 11

* Moves eip-wire-tap to Java 11

* Moves event-aggregator to Java 11

* Moves event-asynchronous to Java 11

* Moves event-driven-architecture to Java 11

* Moves event-queue to Java 11

* Moves event-sourcing to Java 11

* Moves execute-around to Java 11

* Moves extension-objects to Java 11

extension-objects/src/main/java/App.java

@@ -24,7 +24,8 @@
 import abstractextensions.CommanderExtension;
 import abstractextensions.SergeantExtension;
 import abstractextensions.SoldierExtension;
-import org.slf4j.Logger;
+import java.util.Optional;
+import java.util.function.Function;
 import org.slf4j.LoggerFactory;
 import units.CommanderUnit;
 import units.SergeantUnit;
@@ -45,9 +46,9 @@ public class App {
   public static void main(String[] args) {
 
     //Create 3 different units
-    Unit soldierUnit = new SoldierUnit("SoldierUnit1");
-    Unit sergeantUnit = new SergeantUnit("SergeantUnit1");
-    Unit commanderUnit = new CommanderUnit("CommanderUnit1");
+    var soldierUnit = new SoldierUnit("SoldierUnit1");
+    var sergeantUnit = new SergeantUnit("SergeantUnit1");
+    var commanderUnit = new CommanderUnit("CommanderUnit1");
 
     //check for each unit to have an extension
     checkExtensionsForUnit(soldierUnit);
@@ -57,32 +58,24 @@ public class App {
   }
 
   private static void checkExtensionsForUnit(Unit unit) {
-    final Logger logger = LoggerFactory.getLogger(App.class);
+    final var logger = LoggerFactory.getLogger(App.class);
 
-    SoldierExtension soldierExtension =
-        (SoldierExtension) unit.getUnitExtension("SoldierExtension");
-    SergeantExtension sergeantExtension =
-        (SergeantExtension) unit.getUnitExtension("SergeantExtension");
-    CommanderExtension commanderExtension =
-        (CommanderExtension) unit.getUnitExtension("CommanderExtension");
+    var name = unit.getName();
+    Function<String, Runnable> func = (e) -> () -> logger.info(name + " without " + e);
 
-    //if unit have extension call the method
-    if (soldierExtension != null) {
-      soldierExtension.soldierReady();
-    } else {
-      logger.info(unit.getName() + " without SoldierExtension");
-    }
+    var extension = "SoldierExtension";
+    Optional.ofNullable(unit.getUnitExtension(extension))
+        .map(e -> (SoldierExtension) e)
+        .ifPresentOrElse(SoldierExtension::soldierReady, func.apply(extension));
 
-    if (sergeantExtension != null) {
-      sergeantExtension.sergeantReady();
-    } else {
-      logger.info(unit.getName() + " without SergeantExtension");
-    }
+    extension = "SergeantExtension";
+    Optional.ofNullable(unit.getUnitExtension(extension))
+        .map(e -> (SergeantExtension) e)
+        .ifPresentOrElse(SergeantExtension::sergeantReady, func.apply(extension));
 
-    if (commanderExtension != null) {
-      commanderExtension.commanderReady();
-    } else {
-      logger.info(unit.getName() + " without CommanderExtension");
-    }
+    extension = "CommanderExtension";
+    Optional.ofNullable(unit.getUnitExtension(extension))
+        .map(e -> (CommanderExtension) e)
+        .ifPresentOrElse(CommanderExtension::commanderReady, func.apply(extension));
   }
 }

extension-objects/src/main/java/units/CommanderUnit.java

@@ -25,6 +25,7 @@ package units;
 
 import abstractextensions.UnitExtension;
 import concreteextensions.Commander;
+import java.util.Optional;
 
 /**
  * Class defining CommanderUnit.
@@ -39,10 +40,7 @@ public class CommanderUnit extends Unit {
   public UnitExtension getUnitExtension(String extensionName) {
 
     if (extensionName.equals("CommanderExtension")) {
-      if (unitExtension == null) {
-        unitExtension = new Commander(this);
-      }
-      return unitExtension;
+      return Optional.ofNullable(unitExtension).orElseGet(() -> new Commander(this));
     }
 
     return super.getUnitExtension(extensionName);

extension-objects/src/main/java/units/SergeantUnit.java

@@ -25,6 +25,7 @@ package units;
 
 import abstractextensions.UnitExtension;
 import concreteextensions.Sergeant;
+import java.util.Optional;
 
 /**
  * Class defining SergeantUnit.
@@ -39,10 +40,7 @@ public class SergeantUnit extends Unit {
   public UnitExtension getUnitExtension(String extensionName) {
 
     if (extensionName.equals("SergeantExtension")) {
-      if (unitExtension == null) {
-        unitExtension = new Sergeant(this);
-      }
-      return unitExtension;
+      return Optional.ofNullable(unitExtension).orElseGet(() -> new Sergeant(this));
     }
 
     return super.getUnitExtension(extensionName);

extension-objects/src/main/java/units/SoldierUnit.java

@@ -25,6 +25,7 @@ package units;
 
 import abstractextensions.UnitExtension;
 import concreteextensions.Soldier;
+import java.util.Optional;
 
 /**
  * Class defining SoldierUnit.
@@ -39,12 +40,9 @@ public class SoldierUnit extends Unit {
   public UnitExtension getUnitExtension(String extensionName) {
 
     if (extensionName.equals("SoldierExtension")) {
-      if (unitExtension == null) {
-        unitExtension = new Soldier(this);
-      }
-
-      return unitExtension;
+      return Optional.ofNullable(unitExtension).orElseGet(() -> new Soldier(this));
     }
+
     return super.getUnitExtension(extensionName);
   }
 }