Generate a _type attribute with the target class for min, max, range etc

We are especially interested in the target types of numbers and datetime types if we want to simplify or optimise the min, max, range, size etc adapters as they can be created knowning the specific type that is being validated.

Author: rbygrave

validator-generator/src/main/java/io/avaje/validation/generator/AnnotationUtil.java

@@ -1,5 +1,6 @@
 package io.avaje.validation.generator;
 
+import static io.avaje.validation.generator.Util.trimAnnotations;
 import static java.util.function.Predicate.not;
 import static java.util.stream.Collectors.joining;
 import static java.util.stream.Collectors.toMap;
@@ -19,12 +20,13 @@
 import javax.lang.model.element.TypeElement;
 import javax.lang.model.element.VariableElement;
 import javax.lang.model.type.ArrayType;
+import javax.lang.model.type.TypeMirror;
 import javax.lang.model.util.ElementFilter;
 
 final class AnnotationUtil {
 
   interface Handler {
-    String attributes(AnnotationMirror annotationMirror, Element element);
+    String attributes(AnnotationMirror annotationMirror, Element element, Element target);
 
     String attributes(Map<String, Object> attributeMap);
   }
@@ -43,16 +45,12 @@ interface Handler {
     handlers.put("jakarta.validation.constraints.DecimalMax", decimalHandler);
     handlers.put("jakarta.validation.constraints.DecimalMin", decimalHandler);
 
-    final var commonHandler = new CommonHandler();
-    final String[] keys = {
-      "AssertFalse",
-      "AssertTrue",
-      "Null",
-      "NotNull",
-      "NotBlank",
-      "NotEmpty",
+    final String[] withTypeKeys = {
+      "Length",
+      "Range",
+      "Max",
+      "Min",
       "Size",
-      "Email",
       "Past",
       "PastOrPresent",
       "Future",
@@ -62,8 +60,21 @@ interface Handler {
       "PositiveOrZero",
       "Negative",
       "NegativeOrZero",
-      "Max",
-      "Min"
+    };
+    var c = new CommonWithTypeHandler();
+    for (final String key : withTypeKeys) {
+      handlers.put("io.avaje.validation.constraints." + key, c);
+      handlers.put("jakarta.validation.constraints." + key, c);
+    }
+    final var commonHandler = new CommonHandler();
+    final String[] keys = {
+      "AssertFalse",
+      "AssertTrue",
+      "Null",
+      "NotNull",
+      "NotBlank",
+      "NotEmpty",
+      "Email",
     };
     for (final String key : keys) {
       handlers.put("io.avaje.validation.constraints." + key, commonHandler);
@@ -73,11 +84,11 @@ interface Handler {
 
   private AnnotationUtil() {}
 
-  static String annotationAttributeMap(AnnotationMirror annotationMirror) {
+  static String annotationAttributeMap(AnnotationMirror annotationMirror, Element target) {
     final Element element = annotationMirror.getAnnotationType().asElement();
     final Handler handler = handlers.get(element.toString());
     return Objects.requireNonNullElse(handler, defaultHandler)
-        .attributes(annotationMirror, element);
+        .attributes(annotationMirror, element, target);
   }
 
   static String annotationAttributeMap(String annotationStr) {
@@ -221,7 +232,7 @@ private static String avajeKey(String messageKey) {
   static class PatternHandler extends BaseHandler {
 
     @Override
-    public String attributes(AnnotationMirror annotationMirror, Element element) {
+    public String attributes(AnnotationMirror annotationMirror, Element element, Element target) {
       return new PatternHandler().writeAttributes(annotationMirror);
     }
 
@@ -289,21 +300,24 @@ static class StandardHandler extends BaseHandler {
 
     protected final AnnotationMirror annotationMirror;
     protected final Element element;
+    protected final Element target;
 
     /** Prototype factory */
     StandardHandler() {
       this.annotationMirror = null;
       this.element = null;
+      this.target = null;
     }
 
-    StandardHandler(AnnotationMirror annotationMirror, Element element) {
+    StandardHandler(AnnotationMirror annotationMirror, Element element, Element target) {
       this.annotationMirror = annotationMirror;
       this.element = element;
+      this.target = target;
     }
 
     @Override
-    public String attributes(AnnotationMirror annotationMirror, Element element) {
-      return new StandardHandler(annotationMirror, element).writeAttributes();
+    public String attributes(AnnotationMirror annotationMirror, Element element, Element target) {
+      return new StandardHandler(annotationMirror, element, target).writeAttributes();
     }
 
     String writeAttributes() {
@@ -316,10 +330,15 @@ String writeAttributes() {
         }
         writeAttribute(member.getSimpleName(), value, defaultValue);
       }
+      writeTypeAttribute(target.asType());
       sb.append(")");
       return sb.toString();
     }
 
+    protected void writeTypeAttribute(TypeMirror typeMirror) {
+      // do nothing by default
+    }
+
     void writeAttribute(Name simpleName, AnnotationValue value, AnnotationValue defaultValue) {
       writeAttributeKey(simpleName.toString());
       if (value != null) {
@@ -365,18 +384,39 @@ public String attributes(Map<String, Object> attributeMap) {
     }
   }
 
+  static class CommonWithTypeHandler extends CommonHandler {
+
+    CommonWithTypeHandler(AnnotationMirror annotationMirror, Element element, Element target) {
+      super(annotationMirror, element, target);
+    }
+
+    CommonWithTypeHandler() {
+    }
+
+    @Override
+    public String attributes(AnnotationMirror annotationMirror, Element element, Element target) {
+      return new CommonWithTypeHandler(annotationMirror, element, target).writeAttributes();
+    }
+
+    @Override
+    protected void writeTypeAttribute(TypeMirror typeMirror) {
+      writeAttributeKey("_type");
+      sb.append(trimAnnotations(typeMirror.toString()) + ".class");
+    }
+  }
+
   static class CommonHandler extends StandardHandler {
 
     /** Prototype factory only */
     CommonHandler() {}
 
-    CommonHandler(AnnotationMirror annotationMirror, Element element) {
-      super(annotationMirror, element);
+    CommonHandler(AnnotationMirror annotationMirror, Element element, Element target) {
+      super(annotationMirror, element, target);
     }
 
     @Override
-    public String attributes(AnnotationMirror annotationMirror, Element element) {
-      return new CommonHandler(annotationMirror, element).writeAttributes();
+    public String attributes(AnnotationMirror annotationMirror, Element element, Element target) {
+      return new CommonHandler(annotationMirror, element, target).writeAttributes();
     }
 
     @Override
@@ -405,12 +445,12 @@ static class DecimalHandler extends CommonHandler {
     DecimalHandler() {}
 
     @Override
-    public String attributes(AnnotationMirror annotationMirror, Element element) {
-      return new DecimalHandler(annotationMirror, element).writeAttributes();
+    public String attributes(AnnotationMirror annotationMirror, Element element, Element target) {
+      return new DecimalHandler(annotationMirror, element, target).writeAttributes();
     }
 
-    DecimalHandler(AnnotationMirror annotationMirror, Element element) {
-      super(annotationMirror, element);
+    DecimalHandler(AnnotationMirror annotationMirror, Element element, Element target) {
+      super(annotationMirror, element, target);
     }
 
     @Override

validator-generator/src/main/java/io/avaje/validation/generator/ContraintReader.java

@@ -38,7 +38,7 @@ final class ContraintReader implements BeanReader {
             .collect(
                 toMap(
                     a -> GenericType.parse(a.getAnnotationType().toString()),
-                    AnnotationUtil::annotationAttributeMap));
+                    a -> AnnotationUtil.annotationAttributeMap(a, element)));
   }
 
   private List<AnnotationMirror> expand(AnnotationMirror m, List<AnnotationMirror> mirrors) {

validator-generator/src/main/java/io/avaje/validation/generator/ElementAnnotationContainer.java

@@ -52,7 +52,7 @@ static ElementAnnotationContainer create(Element element) {
             .collect(
                 toMap(
                     a -> GenericType.parse(a.getAnnotationType().toString()),
-                    AnnotationUtil::annotationAttributeMap));
+                    a -> AnnotationUtil.annotationAttributeMap(a, element)));
 
     return new ElementAnnotationContainer(genericType, hasValid, annotations, typeUse1, typeUse2);
   }