WW-3714 Shortcut adapters

core/src/main/java/com/opensymphony/xwork2/ActionContext.java

@@ -44,6 +44,9 @@ public class ActionContext extends org.apache.struts2.ActionContext {
     }
 
     public static ActionContext adapt(org.apache.struts2.ActionContext actualContext) {
+        if (actualContext instanceof ActionContext) {
+            return (ActionContext) actualContext;
+        }
         return actualContext != null ? new ActionContext(actualContext) : null;
     }
 

core/src/main/java/com/opensymphony/xwork2/ActionEventListener.java

@@ -43,6 +43,9 @@ public interface ActionEventListener extends org.apache.struts2.ActionEventListe
     String handleException(Throwable t, ValueStack stack);
 
     static ActionEventListener adapt(org.apache.struts2.ActionEventListener actualListener) {
+        if (actualListener instanceof ActionEventListener) {
+            return (ActionEventListener) actualListener;
+        }
         return actualListener != null ? new LegacyAdapter(actualListener) : null;
     }
 

core/src/main/java/com/opensymphony/xwork2/ActionInvocation.java

@@ -63,6 +63,9 @@ public interface ActionInvocation extends org.apache.struts2.ActionInvocation {
     void init(ActionProxy proxy);
 
     static ActionInvocation adapt(org.apache.struts2.ActionInvocation actualInvocation) {
+        if (actualInvocation instanceof ActionInvocation) {
+            return (ActionInvocation) actualInvocation;
+        }
         return actualInvocation != null ? new LegacyAdapter(actualInvocation) : null;
     }
 

core/src/main/java/com/opensymphony/xwork2/ActionProxy.java

@@ -27,6 +27,9 @@ public interface ActionProxy extends org.apache.struts2.ActionProxy {
     ActionInvocation getInvocation();
 
     static ActionProxy adapt(org.apache.struts2.ActionProxy actualProxy) {
+        if (actualProxy instanceof ActionProxy) {
+            return (ActionProxy) actualProxy;
+        }
         return actualProxy != null ? new LegacyAdapter(actualProxy) : null;
     }
 

core/src/main/java/com/opensymphony/xwork2/Result.java

@@ -34,6 +34,9 @@ public interface Result extends org.apache.struts2.Result {
     void execute(ActionInvocation invocation) throws Exception;
 
     static Result adapt(org.apache.struts2.Result actualResult) {
+        if (actualResult instanceof Result) {
+            return (Result) actualResult;
+        }
         return actualResult != null ? new LegacyAdapter(actualResult) : null;
     }
 

core/src/main/java/com/opensymphony/xwork2/interceptor/PreResultListener.java

@@ -36,6 +36,9 @@ public interface PreResultListener extends org.apache.struts2.interceptor.PreRes
     void beforeResult(ActionInvocation invocation, String resultCode);
 
     static PreResultListener adapt(org.apache.struts2.interceptor.PreResultListener actualListener) {
+        if (actualListener instanceof PreResultListener) {
+            return (PreResultListener) actualListener;
+        }
         return actualListener != null ? new LegacyAdapter(actualListener) : null;
     }
 

core/src/main/java/com/opensymphony/xwork2/util/ValueStack.java

@@ -32,6 +32,9 @@ public interface ValueStack extends org.apache.struts2.util.ValueStack {
     ActionContext getActionContext();
 
     static ValueStack adapt(org.apache.struts2.util.ValueStack actualStack) {
+        if (actualStack instanceof ValueStack) {
+            return (ValueStack) actualStack;
+        }
         return actualStack != null ? new LegacyAdapter(actualStack) : null;
     }