Fix #1088

Author: cowtowncoder

release-notes/CREDITS

@@ -281,6 +281,8 @@ Laird Nelson (ljnelson@github)
   * Suggested #688: Provide a means for an ObjectMapper to discover mixin annotation
     classes on demand
    (2.6.0)
+  * Reported #1088: NPE possibility in SimpleMixinResolver
+   (2.6.6)
 
 Derk Norton (derknorton@github)
   * Suggested #689: Add `ObjectMapper.setDefaultPrettyPrinter(PrettyPrinter)`

release-notes/VERSION

@@ -4,6 +4,11 @@ Project: jackson-databind
 === Releases ===
 ------------------------------------------------------------------------
 
+2.6.6 (not released yet)
+
+#1088: NPE possibility in SimpleMixinResolver
+ (reported by Laird N)
+
 2.6.5 (19-Jan-2016)
 
 #1052: Don't generate a spurious NullNode after parsing an embedded object

src/main/java/com/fasterxml/jackson/databind/deser/std/DateDeserializers.java

@@ -6,10 +6,8 @@
 import java.util.*;
 
 import com.fasterxml.jackson.annotation.JsonFormat;
-
 import com.fasterxml.jackson.core.JsonParser;
 import com.fasterxml.jackson.core.JsonToken;
-
 import com.fasterxml.jackson.databind.BeanProperty;
 import com.fasterxml.jackson.databind.DeserializationContext;
 import com.fasterxml.jackson.databind.DeserializationFeature;
@@ -18,6 +16,7 @@
 import com.fasterxml.jackson.databind.annotation.JacksonStdImpl;
 import com.fasterxml.jackson.databind.deser.ContextualDeserializer;
 import com.fasterxml.jackson.databind.introspect.Annotated;
+import com.fasterxml.jackson.databind.jsontype.TypeDeserializer;
 import com.fasterxml.jackson.databind.util.StdDateFormat;
 
 /**
@@ -98,7 +97,7 @@ protected DateBasedDeserializer(DateBasedDeserializer<T> base,
         }
 
         protected abstract DateBasedDeserializer<T> withDateFormat(DateFormat df, String formatStr);
-        
+
         @Override
         public JsonDeserializer<?> createContextual(DeserializationContext ctxt, BeanProperty property)
            throws JsonMappingException
@@ -160,7 +159,7 @@ protected java.util.Date _parseDate(JsonParser p, DeserializationContext ctxt)
                         }
                     }
                 }
-                // Issue#381
+                // [databind#381]
                 if (t == JsonToken.START_ARRAY && ctxt.isEnabled(DeserializationFeature.UNWRAP_SINGLE_VALUE_ARRAYS)) {
                     p.nextToken();
                     final Date parsed = _parseDate(p, ctxt);
@@ -175,7 +174,7 @@ protected java.util.Date _parseDate(JsonParser p, DeserializationContext ctxt)
             return super._parseDate(p, ctxt);
         }
     }
-    
+
     /*
     /**********************************************************
     /* Deserializer implementations for Date types

src/main/java/com/fasterxml/jackson/databind/introspect/SimpleMixInResolver.java

@@ -61,12 +61,13 @@ public SimpleMixInResolver withoutLocalDefinitions() {
     public void setLocalDefinitions(Map<Class<?>, Class<?>> sourceMixins) {
         if (sourceMixins == null || sourceMixins.isEmpty()) {
             _localMixIns = null;
+        } else {
+            Map<ClassKey,Class<?>> mixIns = new HashMap<ClassKey,Class<?>>(sourceMixins.size());
+            for (Map.Entry<Class<?>,Class<?>> en : sourceMixins.entrySet()) {
+                mixIns.put(new ClassKey(en.getKey()), en.getValue());
+            }
+            _localMixIns = mixIns;
         }
-        Map<ClassKey,Class<?>> mixIns = new HashMap<ClassKey,Class<?>>(sourceMixins.size());
-        for (Map.Entry<Class<?>,Class<?>> en : sourceMixins.entrySet()) {
-            mixIns.put(new ClassKey(en.getKey()), en.getValue());
-        }
-        _localMixIns = mixIns;
     }
 
     public void addLocalDefinition(Class<?> target, Class<?> mixinSource) {