jooby-apt: kotlin: mvc: don't generate primitive types with generics type

- test: allow to generate kotlin source code from Java input, just for testing purpose
- Add suppress unchecked warnings
- fix #3490

Author: jknack

modules/jooby-apt/src/main/java/io/jooby/apt/JoobyProcessor.java

@@ -58,7 +58,7 @@ static String string(ProcessingEnvironment environment, String option, String de
     }
   }
 
-  private MvcContext context;
+  protected MvcContext context;
   private Consumer<String> output;
   private final Set<Object> processed = new HashSet<>();
 
@@ -96,7 +96,7 @@ public boolean process(Set<? extends TypeElement> annotations, RoundEnvironment
       var routeMap = buildRouteRegistry(annotations, roundEnv);
       for (var router : routeMap.values()) {
         try {
-          var sourceCode = router.toSourceCode();
+          var sourceCode = router.toSourceCode(null);
           var sourceLocation = router.getGeneratedFilename();
           onGeneratedSource(toJavaFileObject(sourceLocation, sourceCode));
           context.debug("router %s: %s", router.getTargetType(), router.getGeneratedType());

modules/jooby-apt/src/main/java/io/jooby/internal/apt/CodeBlock.java

@@ -43,14 +43,14 @@ public static String type(boolean kt, CharSequence value) {
     var result = value.toString().replace("java.lang.", "");
     if (kt) {
       return switch (result) {
-        case "byte" -> "Byte";
-        case "boolean" -> "Boolean";
+        case "byte", "Byte" -> "Byte";
+        case "boolean", "Boolean" -> "Boolean";
         case "char", "Character" -> "Char";
         case "int", "Integer" -> "Int";
-        case "short" -> "Short";
-        case "long" -> "Long";
-        case "double" -> "Double";
-        case "float" -> "Float";
+        case "short", "Short" -> "Short";
+        case "long", "Long" -> "Long";
+        case "double", "Double" -> "Double";
+        case "float", "Float" -> "Float";
         case "Object" -> "Any";
         default -> {
           var arg = result.indexOf('<');

modules/jooby-apt/src/main/java/io/jooby/internal/apt/MvcRoute.java

@@ -29,6 +29,7 @@ public class MvcRoute {
   private final TypeDefinition returnType;
   private String generatedName;
   private final boolean suspendFun;
+  private boolean uncheckedCast;
 
   public MvcRoute(MvcContext context, MvcRouter router, ExecutableElement method) {
     this.context = context;
@@ -297,11 +298,19 @@ public List<String> generateHandlerCall(boolean kt) {
               kotlinNotEnoughTypeInformation,
               paramList.toString());
       if (!cast.isEmpty()) {
+        setUncheckedCast(true);
         call = kt ? call + " as " + returnTypeString : "(" + returnTypeString + ") " + call;
       }
       buffer.add(statement(indent(2), "return ", call, semicolon(kt)));
     }
     buffer.add(statement("}", System.lineSeparator()));
+    if (uncheckedCast) {
+      if (kt) {
+        buffer.add(0, statement("@Suppress(\"UNCHECKED_CAST\")"));
+      } else {
+        buffer.add(0, statement("@SuppressWarnings(\"unchecked\")"));
+      }
+    }
     return buffer;
   }
 
@@ -452,4 +461,8 @@ private String javadocComment(boolean kt) {
         String.join(", ", getRawParameterTypes(true)),
         ") */");
   }
+
+  public void setUncheckedCast(boolean value) {
+    this.uncheckedCast = value;
+  }
 }

modules/jooby-apt/src/main/java/io/jooby/internal/apt/MvcRouter.java

@@ -107,8 +107,8 @@ public String getPackageName() {
    *
    * @return
    */
-  public String toSourceCode() throws IOException {
-    var kt = isKt();
+  public String toSourceCode(Boolean generateKotlin) throws IOException {
+    var kt = generateKotlin == Boolean.TRUE || isKt();
     var generateTypeName = context.generateRouterName(getTargetType().getSimpleName().toString());
     try (var in = getClass().getResourceAsStream("Source" + (kt ? ".kt" : ".java"))) {
       Objects.requireNonNull(in);

modules/jooby-apt/src/main/java/io/jooby/internal/apt/ParameterGenerator.java

@@ -31,6 +31,7 @@ public String toSourceCode(
         boolean nullable) {
       if (type.is(Map.class)) {
         if (kt) {
+          route.setUncheckedCast(true);
           return CodeBlock.of(
               "(ctx.attributes[",
               CodeBlock.string(name),
@@ -42,17 +43,13 @@ public String toSourceCode(
               ")).orElseGet(() ->" + " ctx.getAttributes())");
         }
       } else {
-        return kt
-            ? CodeBlock.of(
-                "ctx.", method, "(", CodeBlock.string(name), ") as ", type.getRawType().toString())
-            : CodeBlock.of(
-                "(",
-                type.getRawType().toString(),
-                ") ctx.",
-                method,
-                "(",
-                CodeBlock.string(name),
-                ")");
+        if (kt) {
+          route.setUncheckedCast(true);
+          return CodeBlock.of(
+              "ctx.", method, "(", CodeBlock.string(name), ") as ", type.getRawType().toString());
+        }
+        return CodeBlock.of(
+            "(", type.getRawType().toString(), ") ctx.", method, "(", CodeBlock.string(name), ")");
       }
     }
   },
@@ -234,6 +231,7 @@ public String toSourceCode(
           var prefix = "";
           var suffix = "";
           if (toValue.getValue().isParameterizedType()) {
+            route.setUncheckedCast(true);
             prefix = "(";
             suffix = ") as " + CodeBlock.type(true, toValue.getValue().toString());
           }

modules/jooby-apt/src/main/java/io/jooby/internal/apt/TypeDefinition.java

@@ -31,7 +31,7 @@ public TypeDefinition(Types types, TypeMirror type) {
   }
 
   public String toSourceCode(boolean kt) {
-    return toSourceCode(this, kt);
+    return toSourceCode(this, kt, false);
   }
 
   public String getArgumentsString(boolean kt, boolean convertTypeVar, Set<TypeKind> kinds) {
@@ -54,7 +54,7 @@ public String getArgumentsString(boolean kt, boolean convertTypeVar, Set<TypeKin
         .collect(Collectors.joining(", ", "<", "> "));
   }
 
-  private static String toSourceCode(TypeDefinition type, boolean kt) {
+  private static String toSourceCode(TypeDefinition type, boolean kt, boolean generics) {
     if (type.isParameterizedType()) {
       var buffer = new StringBuilder();
       var methodName =
@@ -78,12 +78,16 @@ private static String toSourceCode(TypeDefinition type, boolean kt) {
             .append(", ");
       }
       for (TypeDefinition arg : type.getArguments()) {
-        buffer.append(toSourceCode(arg, kt)).append(separator);
+        // Generics are always wrapper
+        buffer.append(toSourceCode(arg, kt, true)).append(separator);
       }
       buffer.setLength(buffer.length() - separator.length());
       buffer.append(").getType()");
       return buffer.toString();
     } else {
+      if (generics && kt) {
+        return type.getRawType().toString().replace("java.lang.", "") + clazz(kt);
+      }
       return CodeBlock.type(kt, type.getRawType().toString()) + clazz(kt);
     }
   }

modules/jooby-apt/src/test/java/io/jooby/apt/ProcessorRunner.java

@@ -25,6 +25,7 @@
 import com.google.testing.compile.JavaFileObjects;
 import com.google.testing.compile.JavaSourcesSubjectFactory;
 import io.jooby.*;
+import io.jooby.internal.apt.MvcContext;
 
 public class ProcessorRunner {
 
@@ -71,6 +72,10 @@ public JavaFileObject getSource() {
       return source;
     }
 
+    public MvcContext getContext() {
+      return context;
+    }
+
     @Override
     protected void onGeneratedSource(JavaFileObject source) {
       this.source = source;
@@ -117,6 +122,12 @@ public ProcessorRunner withSource(SneakyThrows.Consumer<JavaFileObject> consumer
     return this;
   }
 
+  public ProcessorRunner withSource(boolean kt, SneakyThrows.Consumer<String> consumer)
+      throws IOException {
+    consumer.accept(processor.getContext().getRouters().get(0).toSourceCode(kt));
+    return this;
+  }
+
   private String[] sourceNames(Class input) {
     List<String> result = new ArrayList<>();
     while (input != Object.class) {

modules/jooby-apt/src/test/java/tests/i3490/Box3490.java

@@ -0,0 +1,16 @@
+/*
+ * Jooby https://jooby.io
+ * Apache License Version 2.0 https://jooby.io/LICENSE.txt
+ * Copyright 2014 Edgar Espina
+ */
+package tests.i3490;
+
+public class Box3490<T> {
+  private T value;
+
+  public Box3490(T value) {}
+
+  public T getValue() {
+    return value;
+  }
+}

modules/jooby-apt/src/test/java/tests/i3490/C3490.java

@@ -0,0 +1,17 @@
+/*
+ * Jooby https://jooby.io
+ * Apache License Version 2.0 https://jooby.io/LICENSE.txt
+ * Copyright 2014 Edgar Espina
+ */
+package tests.i3490;
+
+import io.jooby.annotation.GET;
+import io.jooby.annotation.QueryParam;
+
+public class C3490 {
+
+  @GET("/3490")
+  public Box3490<Integer> get(@QueryParam int id) {
+    return null;
+  }
+}

modules/jooby-apt/src/test/java/tests/i3490/Issue3490.java

@@ -0,0 +1,30 @@
+/*
+ * Jooby https://jooby.io
+ * Apache License Version 2.0 https://jooby.io/LICENSE.txt
+ * Copyright 2014 Edgar Espina
+ */
+package tests.i3490;
+
+import static org.junit.jupiter.api.Assertions.assertTrue;
+
+import java.io.IOException;
+
+import org.junit.jupiter.api.Test;
+
+import io.jooby.apt.ProcessorRunner;
+
+public class Issue3490 {
+
+  @Test
+  public void shouldNotGeneratePrimitiveOnKotlinGenerics() throws IOException {
+    new ProcessorRunner(new C3490())
+        .withSource(
+            true,
+            source -> {
+              assertTrue(
+                  source.contains(
+                      ".setReturnType(io.jooby.Reified.getParameterized(tests.i3490.Box3490::class.java,"
+                          + " Integer::class.java).getType())"));
+            });
+  }
+}