Fix #725

Author: cowtowncoder

release-notes/VERSION

@@ -12,6 +12,7 @@ Project: jackson-databind
  (reported by Charles A)
 #700: Cannot Change Default Abstract Type Mapper from LinkedHashMap
  (reported by wealdtech@github)
+#725: Auto-detect multi-argument constructor with implicit names if it is the only visible creator
 - Remove old cglib compatibility tests; cause problems in Eclipse
 
 2.5.2 (not yet released)

src/main/java/com/fasterxml/jackson/databind/deser/BasicDeserializerFactory.java

@@ -6,11 +6,12 @@
 import java.util.concurrent.atomic.AtomicReference;
 
 import com.fasterxml.jackson.annotation.JsonCreator;
+
 import com.fasterxml.jackson.core.JsonLocation;
+
 import com.fasterxml.jackson.databind.*;
 import com.fasterxml.jackson.databind.cfg.DeserializerFactoryConfig;
 import com.fasterxml.jackson.databind.cfg.HandlerInstantiator;
-import com.fasterxml.jackson.databind.cfg.MapperConfig;
 import com.fasterxml.jackson.databind.deser.impl.CreatorCollector;
 import com.fasterxml.jackson.databind.deser.std.*;
 import com.fasterxml.jackson.databind.ext.OptionalHandlerFactory;
@@ -19,11 +20,7 @@
 import com.fasterxml.jackson.databind.jsontype.TypeDeserializer;
 import com.fasterxml.jackson.databind.jsontype.TypeResolverBuilder;
 import com.fasterxml.jackson.databind.type.*;
-import com.fasterxml.jackson.databind.util.ClassUtil;
-import com.fasterxml.jackson.databind.util.EnumResolver;
-import com.fasterxml.jackson.databind.util.NameTransformer;
-import com.fasterxml.jackson.databind.util.SimpleBeanPropertyDefinition;
-import com.fasterxml.jackson.databind.util.TokenBuffer;
+import com.fasterxml.jackson.databind.util.*;
 
 /**
  * Abstract factory base class that can provide deserializers for standard
@@ -495,10 +492,18 @@ public ValueInstantiator _valueInstantiatorInstance(DeserializationConfig config
                 // simple case; everything covered:
                 if ((namedCount + injectCount) == argCount) {
                     creators.addPropertyCreator(ctor, isCreator, properties);
-                } else if ((explicitNameCount == 0) && ((injectCount + 1) == argCount)) {
+                    continue;
+                }
+                if ((explicitNameCount == 0) && ((injectCount + 1) == argCount)) {
                     // Secondary: all but one injectable, one un-annotated (un-named)
                     creators.addDelegatingCreator(ctor, isCreator, properties);
-                } else { // otherwise, epic fail
+                    continue;
+                }
+                // otherwise, epic fail?
+                // 16-Mar-2015, tatu: due to [#725], need to be more permissive. For now let's
+                //    only report problem if there's no implicit name
+                PropertyName impl = _findImplicitParamName(nonAnnotatedParam, intr);
+                if (impl == null || impl.isEmpty()) {
                     // Let's consider non-static inner class as a special case...
                     int ix = nonAnnotatedParam.getIndex();
                     if ((ix == 0) && ClassUtil.isNonStaticInnerClass(ctor.getDeclaringClass())) {
@@ -508,7 +513,6 @@ public ValueInstantiator _valueInstantiatorInstance(DeserializationConfig config
                     throw new IllegalArgumentException("Argument #"+ix
                             +" of constructor "+ctor+" has no property name annotation; must have name when multiple-parameter constructor annotated as Creator");
                 }
-                continue;
             }
             // [#725]: as a fallback, all-implicit names may work as well
             if (!creators.hasDefaultCreator()) {
@@ -518,7 +522,6 @@ public ValueInstantiator _valueInstantiatorInstance(DeserializationConfig config
                 implicitCtors.add(ctor);
             }
         }
-
         // last option, as per [#725]: consider implicit-names-only, visible constructor,
         // if just one found
         if ((implicitCtors != null) && !creators.hasDelegatingCreator()
@@ -546,7 +549,6 @@ protected void _checkImplicitlyNamedConstructors(DeserializationContext ctxt,
                 continue;
             }
             // as per earlier notes, only end up here if no properties associated with creator
-
             final int argCount = ctor.getParameterCount();
             CreatorProperty[] properties = new CreatorProperty[argCount];
             for (int i = 0; i < argCount; ++i) {
@@ -889,21 +891,20 @@ protected PropertyName _findParamName(AnnotatedParameter param, AnnotationIntros
         return null;
     }
 
-    @Deprecated // in 2.6, remove from 2.7
-    protected PropertyName _findExplicitParamName(AnnotatedParameter param, AnnotationIntrospector intr)
+    protected PropertyName _findImplicitParamName(AnnotatedParameter param, AnnotationIntrospector intr)
     {
-        if (param != null && intr != null) {
-            return intr.findNameForDeserialization(param);
+        String str = intr.findImplicitPropertyName(param);
+        if (str != null && !str.isEmpty()) {
+            return PropertyName.construct(str);
         }
         return null;
     }
 
     @Deprecated // in 2.6, remove from 2.7
-    protected PropertyName _findImplicitParamName(AnnotatedParameter param, AnnotationIntrospector intr)
+    protected PropertyName _findExplicitParamName(AnnotatedParameter param, AnnotationIntrospector intr)
     {
-        String str = intr.findImplicitPropertyName(param);
-        if (str != null && !str.isEmpty()) {
-            return PropertyName.construct(str);
+        if (param != null && intr != null) {
+            return intr.findNameForDeserialization(param);
         }
         return null;
     }
@@ -917,7 +918,7 @@ protected boolean _hasExplicitParamName(AnnotatedParameter param, AnnotationIntr
         }
         return false;
     }
-    
+
     /*
     /**********************************************************
     /* JsonDeserializerFactory impl: array deserializers

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

@@ -20,7 +20,7 @@ public class POJOPropertiesCollector
     /* Configuration
     /**********************************************************
      */
-    
+
     /**
      * Configuration settings
      */

src/test/java/com/fasterxml/jackson/failing/MultiArgConstructorTest.java

@@ -78,8 +78,8 @@ public void testMultiArgWithPartialOverride() throws Exception
     {
         final ObjectMapper mapper = new ObjectMapper();
         mapper.setAnnotationIntrospector(new MyParamIntrospector());
-        MultiArgCtorBean bean = mapper.readValue(aposToQuotes("{'b2':7, 'c':222, 'a':-99}"),
-                MultiArgCtorBean.class);
+        MultiArgCtorBeanWithAnnotations bean = mapper.readValue(aposToQuotes("{'b2':7, 'c':222, 'a':-99}"),
+                MultiArgCtorBeanWithAnnotations.class);
         assertNotNull(bean);
         assertEquals(7, bean._b);
         assertEquals(-99, bean._a);