Use OptionalInt instead of Optional<Integer>

Author: mbax

src/main/java/org/kitteh/irc/client/library/defaults/element/isupport/DefaultISupportParameterOptionalInteger.java

@@ -29,7 +29,7 @@
 import org.kitteh.irc.client.library.defaults.element.DefaultISupportParameter;
 import org.kitteh.irc.client.library.element.ISupportParameter;
 
-import java.util.Optional;
+import java.util.OptionalInt;
 
 /**
  * Default implementation of {@link OptionalIntegerParameter}.
@@ -56,7 +56,7 @@ protected DefaultISupportParameterOptionalInteger(@NonNull Client client, @NonNu
     }
 
     @Override
-    public Optional<Integer> getInteger() {
-        return Optional.ofNullable(this.integer);
+    public OptionalInt getInteger() {
+        return this.integer == null ? OptionalInt.empty() : OptionalInt.of(this.integer);
     }
 }

src/main/java/org/kitteh/irc/client/library/element/ISupportParameter.java

@@ -30,6 +30,7 @@
 import java.util.List;
 import java.util.Map;
 import java.util.Optional;
+import java.util.OptionalInt;
 import java.util.Set;
 
 /**
@@ -57,7 +58,7 @@ interface OptionalIntegerParameter extends ISupportParameter {
          *
          * @return the processed value
          */
-        Optional<Integer> getInteger();
+        OptionalInt getInteger();
     }
 
     /**