1 files changed, 42 insertions, 0 deletions
diff --git a/src/main/java/org/junit/validator/AnnotationValidatorFactory.java b/src/main/java/org/junit/validator/AnnotationValidatorFactory.java
new file mode 100644
index 0000000..7309fdd
--- /dev/null
+++ b/src/main/java/org/junit/validator/AnnotationValidatorFactory.java
@@ -0,0 +1,42 @@
+package org.junit.validator;
+
+import java.util.concurrent.ConcurrentHashMap;
+
+/**
+ * Creates instances of Annotation Validators.
+ *
+ * @since 4.12
+ */
+public class AnnotationValidatorFactory {
+    private static final ConcurrentHashMap<ValidateWith, AnnotationValidator> VALIDATORS_FOR_ANNOTATION_TYPES =
+            new ConcurrentHashMap<ValidateWith, AnnotationValidator>();
+
+    /**
+     * Creates the AnnotationValidator specified by the value in
+     * {@link org.junit.validator.ValidateWith}. Instances are
+     * cached.
+     *
+     * @return An instance of the AnnotationValidator.
+     *
+     * @since 4.12
+     */
+    public AnnotationValidator createAnnotationValidator(ValidateWith validateWithAnnotation) {
+        AnnotationValidator validator = VALIDATORS_FOR_ANNOTATION_TYPES.get(validateWithAnnotation);
+        if (validator != null) {
+            return validator;
+        }
+
+        Class<? extends AnnotationValidator> clazz = validateWithAnnotation.value();
+        if (clazz == null) {
+            throw new IllegalArgumentException("Can't create validator, value is null in annotation " + validateWithAnnotation.getClass().getName());
+        }
+        try {
+            AnnotationValidator annotationValidator = clazz.newInstance();
+            VALIDATORS_FOR_ANNOTATION_TYPES.putIfAbsent(validateWithAnnotation, annotationValidator);
+            return VALIDATORS_FOR_ANNOTATION_TYPES.get(validateWithAnnotation);
+        } catch (Exception e) {
+            throw new RuntimeException("Exception received when creating AnnotationValidator class " + clazz.getName(), e);
+        }
+    }
+
+}