Generate anonymous classes in vanilla mode

Author: RikkiGibson

src/JavaBlock.cs

@@ -71,6 +71,11 @@ public void ReturnAnonymousClass(string anonymousClassDeclaration, Action<JavaCl
             contents.ReturnAnonymousClass(anonymousClassDeclaration, anonymousClassBlock);
         }
 
+        public void AnonymousClass(string anonymousClassDeclaration, Action<JavaClass> anonymousClassBlock)
+        {
+            contents.AnonymousClass(anonymousClassDeclaration, anonymousClassBlock);
+        }
+
         public JavaIfBlock If(string condition, Action<JavaBlock> ifAction)
         {
             contents.If(condition, ifAction);

src/JavaCodeGenerator.cs

@@ -4280,14 +4280,19 @@ restAPIMethodReturnBodyClientType is ListType restAPIMethodReturnBodyClientListT
                             }
 
                             IType returnValueTypeArgumentType = ((GenericType)restAPIMethod.ReturnType).TypeArguments.Single();
+                            // TODO: generate anonymous classes for paging
+                            IType mapperReturnType = ((GenericType)returnValueTypeArgumentType).TypeArguments.Last();
 
                             string restAPIMethodArgumentList = GetRestAPIMethodArgumentList(autoRestMethodOrderedRetrofitParameters, settings);
 
                             function.Line($"return service.{restAPIMethod.Name}({restAPIMethodArgumentList})");
                             function.Indent(() =>
                             {
                                 function.Text(".map(");
-                                function.Lambda(returnValueTypeArgumentType.ToString(), "res", "res.body()");
+                                function.AnonymousClass($"new Function<{returnValueTypeArgumentType}, {mapperReturnType}>()", anonymousClass =>
+                                {
+                                    anonymousClass.PublicMethod($"{mapperReturnType} apply(RestResponse<?, ?> res)", method => method.Return("res.body()"));
+                                });
                                 function.Line(");");
                             });
                         });
@@ -4342,12 +4347,18 @@ restAPIMethodReturnBodyClientType is ListType restAPIMethodReturnBodyClientListT
                             ConvertClientTypesToWireTypes(function, autoRestMethodRetrofitParameters, methodClientReference, settings);
 
                             IType returnValueTypeArgumentType = ((GenericType)restAPIMethod.ReturnType).TypeArguments.Single();
+                            IType mapperReturnType = clientMethod.ReturnValue.Type;
+
                             string restAPIMethodArgumentList = GetRestAPIMethodArgumentList(autoRestMethodOrderedRetrofitParameters, settings);
                             function.Line($"return service.{clientMethod.RestAPIMethod.Name}({restAPIMethodArgumentList})");
                             function.Indent(() =>
                             {
                                 function.Text(".map(");
-                                function.Lambda(returnValueTypeArgumentType.ToString(), "res", "res.body()");
+
+                                function.AnonymousClass($"new Function<{returnValueTypeArgumentType}, {mapperReturnType}>()", anonymousClass =>
+                                {
+                                    anonymousClass.PublicMethod($"{mapperReturnType} apply(RestResponse<?, {mapperReturnType}> res)", method => method.Return("res.body()"));
+                                });
                                 function.Line(")");
                                 function.Line(".toObservable();");
                             });
@@ -4551,16 +4562,27 @@ restAPIMethodReturnBodyClientType is ListType restAPIMethodReturnBodyClientListT
                             {
                                 GenericType restAPIMethodClientReturnType = (GenericType)ConvertToClientType(restAPIMethod.ReturnType);
                                 IType returnValueTypeArgumentClientType = restAPIMethodClientReturnType.TypeArguments.Single();
+                                IType mapperReturnType = clientMethod.ReturnValue.Type;
                                 if (restAPIMethodReturnBodyClientType != PrimitiveType.Void)
                                 {
                                     function.Text($".flatMapMaybe(");
-                                    function.Lambda(returnValueTypeArgumentClientType.ToString(), "res", "res.body() == null ? Maybe.empty() : Maybe.just(res.body())");
+                                    function.AnonymousClass($"new Function<{returnValueTypeArgumentClientType}, {mapperReturnType}>()", anonymousClassBlock =>
+                                    {
+                                        anonymousClassBlock.PublicMethod(
+                                            $"{mapperReturnType} apply({returnValueTypeArgumentClientType} res)",
+                                            method => method.Return($"res.body() == null ? Maybe.<{restAPIMethodReturnBodyClientType.AsNullable()}>empty() : Maybe.just(res.body())"));
+                                    });
                                     function.Line(");");
                                 }
                                 else if (isFluentDelete)
                                 {
                                     function.Text($".flatMapMaybe(");
-                                    function.Lambda(returnValueTypeArgumentClientType.ToString(), "res", "Maybe.empty()");
+                                    function.AnonymousClass($"new Function<{returnValueTypeArgumentClientType}, {GenericType.Maybe(ClassType.Void)}>()", anonymousClassBlock =>
+                                    {
+                                        anonymousClassBlock.PublicMethod(
+                                            $"{GenericType.Maybe(ClassType.Void)} apply({returnValueTypeArgumentClientType} res)",
+                                            method => method.Return("Maybe.empty()"));
+                                    });
                                     function.Line(");");
                                 }
                                 else
@@ -5393,7 +5415,7 @@ private static string GetRestAPIMethodArgumentList(IEnumerable<AutoRestParameter
                 });
             return string.Join(", ", restAPIMethodArguments);
         }
-        
+
         private static string AddClientTypePrefix(string clientType, JavaSettings settings)
             => string.IsNullOrEmpty(settings.ClientTypePrefix) ? clientType : settings.ClientTypePrefix + clientType;
     }

src/JavaFileContents.cs

@@ -253,7 +253,7 @@ public void Import(IEnumerable<string> imports)
                 Line();
             }
         }
-        
+
         public void LineComment(string text)
         {
             LineComment(comment =>
@@ -319,11 +319,22 @@ public void ReturnAnonymousClass(string anonymousClassDeclaration, Action<JavaCl
             Indent(() =>
             {
                 JavaClass javaClass = new JavaClass(this);
-                anonymousClassBlock.Invoke(javaClass);
+                anonymousClassBlock(javaClass);
             });
             Line("};");
         }
 
+        public void AnonymousClass(string anonymousClassDeclaration, Action<JavaClass> anonymousClassBlock)
+        {
+            Line($"{anonymousClassDeclaration} {{");
+            Indent(() =>
+            {
+                JavaClass javaClass = new JavaClass(this);
+                anonymousClassBlock(javaClass);
+            });
+            Line("}");
+        }
+
         public void Annotation(params string[] annotations)
         {
             Annotation((IEnumerable<string>)annotations);

src/Model/RestAPIMethod.cs

@@ -154,6 +154,8 @@ public void AddImportsTo(ISet<string> imports, bool includeImplementationImports
 
             if (includeImplementationImports)
             {
+                imports.Add("io.reactivex.functions.Function");
+
                 if (IsResumable)
                 {
                     imports.Add("com.microsoft.rest.v2.annotations.ResumeOperation");