fixed NPE for enum & log cleanup (#51)

Author: jmisur

spring-auto-restdocs-core/src/main/java/capital/scalable/restdocs/constraints/ConstraintAndGroupDescriptionResolver.java

@@ -95,7 +95,8 @@ private String resolvePlainDescription(Constraint constraint) {
         try {
             return delegate.resolveDescription(constraint);
         } catch (MissingResourceException e) {
-            log.info("No description found for constraint {}", constraint.getName(), e);
+            log.warn("No description found for constraint {}: {}", constraint.getName(),
+                    e.getMessage());
             return "";
         }
     }

spring-auto-restdocs-core/src/main/java/capital/scalable/restdocs/constraints/ConstraintReaderImpl.java

@@ -27,6 +27,7 @@
 import static org.apache.commons.lang3.StringUtils.isBlank;
 import static org.springframework.util.ReflectionUtils.findField;
 
+import java.lang.reflect.Field;
 import java.util.ArrayList;
 import java.util.List;
 
@@ -76,10 +77,16 @@ public List<String> getConstraintMessages(MethodParameter param) {
 
     private List<String> getEnumConstraintMessage(Class<?> javaBaseClass, String javaFieldName) {
         // could be getter actually
-        Class<?> rawClass = findField(javaBaseClass, javaFieldName).getType();
-        if (rawClass == null || !rawClass.isEnum()) {
+        Field field = findField(javaBaseClass, javaFieldName);
+        if (field == null) {
             return emptyList();
         }
+
+        Class<?> rawClass = field.getType();
+        if (!rawClass.isEnum()) {
+            return emptyList();
+        }
+
         Class<Enum> enumClass = (Class<Enum>) rawClass;
 
         String value = arrayToString(enumClass.getEnumConstants());