mvc: Add BindParam annotation for custom parsing/mapping

- supports BindParam "sub class" annotation
- ref #3472

Author: jknack

jooby/src/main/java/io/jooby/annotation/BindParam.java

@@ -17,7 +17,7 @@
  * @since 3.2.5
  */
 @Retention(RetentionPolicy.RUNTIME)
-@Target(ElementType.PARAMETER)
+@Target({ElementType.PARAMETER, ElementType.ANNOTATION_TYPE})
 public @interface BindParam {
   /**
    * Class containing the mapping function.

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

@@ -6,12 +6,12 @@
 package io.jooby.internal.apt;
 
 import java.util.*;
-import java.util.function.Function;
 import java.util.function.Predicate;
 import java.util.stream.Collectors;
 import java.util.stream.Stream;
 
 import javax.lang.model.element.AnnotationMirror;
+import javax.lang.model.element.Element;
 import javax.lang.model.element.VariableElement;
 
 public class MvcParameter {
@@ -132,6 +132,17 @@ private Map<String, AnnotationMirror> annotationMap(VariableElement parameter) {
     return Stream.of(parameter.getAnnotationMirrors(), parameter.asType().getAnnotationMirrors())
         .filter(Objects::nonNull)
         .flatMap(List::stream)
-        .collect(Collectors.toMap(it -> it.getAnnotationType().toString(), Function.identity()));
+        .flatMap(
+            it ->
+                Stream.concat(
+                    Stream.of(it),
+                    annotationFromAnnotationType(it.getAnnotationType().asElement()).stream()))
+        .filter(Objects::nonNull)
+        .map(it -> Map.entry(it.getAnnotationType().toString(), it))
+        .collect(Collectors.toMap(Map.Entry::getKey, Map.Entry::getValue, (e1, e2) -> e1));
+  }
+
+  private List<? extends AnnotationMirror> annotationFromAnnotationType(Element element) {
+    return Optional.ofNullable(element.getAnnotationMirrors()).orElse(Collections.emptyList());
   }
 }

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

@@ -161,7 +161,7 @@ public String toSourceCode(
               .orElseThrow(
                   () ->
                       new IllegalArgumentException(
-                          "Method not found: " + converter + "." + methodErrorName));
+                          "Method not found: " + converter + ".[unnamed]" + methodErrorName));
       if (!mapping.getModifiers().contains(Modifier.PUBLIC)) {
         throw new IllegalArgumentException("Method is not public: " + converter + "." + mapping);
       }

modules/jooby-apt/src/test/java/tests/i3472/BeanMapping.java

@@ -0,0 +1,14 @@
+/*
+ * Jooby https://jooby.io
+ * Apache License Version 2.0 https://jooby.io/LICENSE.txt
+ * Copyright 2014 Edgar Espina
+ */
+package tests.i3472;
+
+import io.jooby.Context;
+
+public class BeanMapping {
+  public static BindBean map(Context ctx) {
+    return new BindBean("extends:" + ctx.query("value").value());
+  }
+}

modules/jooby-apt/src/test/java/tests/i3472/C3472.java

@@ -26,6 +26,11 @@ public BindBean bindStatic(@BindParam(BindBean.class) BindBean bean) {
     return bean;
   }
 
+  @GET("/3472/extends")
+  public BindBean bindExtends(@SubAnnotation BindBean bean) {
+    return bean;
+  }
+
   public BindBean convert(Context ctx) {
     return new BindBean(ctx.query("value").value());
   }

modules/jooby-apt/src/test/java/tests/i3472/Issue3472.java

@@ -30,6 +30,9 @@ public void shouldBindWithCustomCode() throws Exception {
 
               assertEquals(
                   new BindBean("static:" + value), router.get("/3472/static", ctx).value());
+
+              assertEquals(
+                  new BindBean("extends:" + value), router.get("/3472/extends", ctx).value());
             });
   }
 }

modules/jooby-apt/src/test/java/tests/i3472/SubAnnotation.java

@@ -0,0 +1,11 @@
+/*
+ * Jooby https://jooby.io
+ * Apache License Version 2.0 https://jooby.io/LICENSE.txt
+ * Copyright 2014 Edgar Espina
+ */
+package tests.i3472;
+
+import io.jooby.annotation.BindParam;
+
+@BindParam(BeanMapping.class)
+public @interface SubAnnotation {}