Fix issue with non-Optional generic parameters in controller methods throwing an exception (#764)

* Fix issue with non-Optional generic parameters in controller methods throwing an exception

Author: dpoineau

ninja-core/src/main/java/ninja/params/ControllerMethodInvoker.java

@@ -417,6 +417,13 @@ private MethodParameter(Type genericType) {
                     if (maybeOptional.isAssignableFrom(Optional.class)) {
                         isOptional = true;
                         parameterClass = getClass(parameterizedType.getActualTypeArguments()[0]);
+                    } else {
+                        // This case is necessary here for types like List<String>
+                        // because genericType is not a class in that case, so letting it fall through below throws an exception.
+                        // So we explicitly handle the case here and use parameterizedType.getRawType() as the parameterClass
+                        // (which would be List in the example above), and matches the behavior of older Ninja versions.
+                        isOptional = false;
+                        parameterClass = maybeOptional;
                     }
                 }
 

ninja-core/src/test/java/ninja/params/ControllerMethodInvokerTest.java

@@ -58,6 +58,7 @@
 import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.Date;
+import java.util.List;
 import java.util.Optional;
 
 import static org.junit.Assert.*;
@@ -1073,6 +1074,14 @@ public void bodyWithOptionalShouldBeEmptyIfNoBodyPresent() {
         verify(mockController).bodyWithOptional(Optional.empty());
     }
 
+    @Test
+    public void bodyWithGenericTypeShouldRun() {
+        List<String> body = Arrays.asList("value1", "value2");
+        when(context.parseBody(List.class)).thenReturn(body);
+        create("bodyWithGenericType").invoke(mockController, context);
+        verify(mockController).bodyWithGenericType(body);
+    }
+
     // JSR303Validation(@Pattern(regexp = "[a-z]*") String param1,
     // @Length(min = 5, max = 10) String param2, @Min(3) @Max(10) int param3);
     @Test
@@ -1426,6 +1435,8 @@ public Result multiple(@Param("param1") String param1, @PathParam("param2") int
         public Result badValidatorWithOptional(@Param("param1") @NumberValue(min = 10) Optional<String> param1);
 
         public Result body(Object body);
+
+        public Result bodyWithGenericType(List<String> myList);
 
         public Result bodyWithOptional(Optional<Object> body);