More work on #4515: start refactoring BasicDeserializerFactory (#4539)

src/main/java/com/fasterxml/jackson/databind/BeanDescription.java

@@ -14,9 +14,9 @@
 /**
  * Basic container for information gathered by {@link ClassIntrospector} to
  * help in constructing serializers and deserializers.
- * Note that the main implementation type is
+ * Note that the one implementation type is
  * {@link com.fasterxml.jackson.databind.introspect.BasicBeanDescription},
- * meaning that it is safe to upcast to this type.
+ * meaning that it is safe to upcast to that type.
  */
 public abstract class BeanDescription
 {
@@ -109,7 +109,7 @@ public boolean isNonStaticInnerClass() {
 
     /*
     /**********************************************************
-    /* Basic API for finding creator members
+    /* Basic API for finding Creators, related information
     /**********************************************************
      */
 
@@ -166,6 +166,15 @@ public boolean isNonStaticInnerClass() {
      */
     public abstract AnnotatedConstructor findDefaultConstructor();
 
+    /**
+     * Method that is replacing earlier Creator introspection access methods.
+     *
+     * @since 2.18
+     *
+     * @return Container for introspected Creator candidates, if any
+     */
+    public abstract PotentialCreators getPotentialCreators();
+
     /*
     /**********************************************************
     /* Basic API for finding property accessors

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

@@ -623,12 +623,6 @@ protected void _addExplicitFactoryCreators(DeserializationContext ctxt,
                 continue;
             }
 
-            // zero-arg method factory methods fine, as long as explicit
-            if (argCount == 0) {
-                creators.setDefaultCreator(factory);
-                continue;
-            }
-
             switch (creatorMode) {
             case DELEGATING:
                 _addExplicitDelegatingCreator(ctxt, beanDesc, creators,
@@ -707,34 +701,8 @@ protected void _addImplicitFactoryCreators(DeserializationContext ctxt,
                 NameTransformer unwrapper = intr.findUnwrappingNameTransformer(param);
                 if (unwrapper != null) {
                     _reportUnwrappedCreatorProperty(ctxt, beanDesc, param);
-                    /*
-                    properties[i] = constructCreatorProperty(ctxt, beanDesc, UNWRAPPED_CREATOR_PARAM_NAME, i, param, null);
-                    ++implicitNameCount;
-                    */
                     continue;
                 }
-                // One more thing: implicit names are ok iff ctor has creator annotation
-                /*
-                if (isCreator) {
-                    if (name != null && !name.isEmpty()) {
-                        ++implicitNameCount;
-                        properties[i] = constructCreatorProperty(ctxt, beanDesc, name, i, param, injectable);
-                        continue;
-                    }
-                }
-                */
-                /* 25-Sep-2014, tatu: Actually, we may end up "losing" naming due to higher-priority constructor
-                 *  (see TestCreators#testConstructorCreator() test). And just to avoid running into that problem,
-                 *  let's add one more work around
-                 */
-                /*
-                PropertyName name2 = _findExplicitParamName(param, intr);
-                if (name2 != null && !name2.isEmpty()) {
-                    // Hmmh. Ok, fine. So what are we to do with it... ?
-                    // For now... skip. May need to revisit this, should this become problematic
-                    continue main_loop;
-                }
-                */
                 if (nonAnnotatedParam == null) {
                     nonAnnotatedParam = param;
                 }
@@ -841,10 +809,6 @@ protected void _addExplicitPropertyCreator(DeserializationContext ctxt,
                 NameTransformer unwrapper = ctxt.getAnnotationIntrospector().findUnwrappingNameTransformer(param);
                 if (unwrapper != null) {
                     _reportUnwrappedCreatorProperty(ctxt, beanDesc, param);
-                    /*
-                    properties[i] = constructCreatorProperty(ctxt, beanDesc, UNWRAPPED_CREATOR_PARAM_NAME, i, param, null);
-                    ++explicitNameCount;
-                    */
                 }
                 name = candidate.findImplicitParamName(i);
                 _validateNamedPropertyParameter(ctxt, beanDesc, candidate, i,

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

@@ -340,6 +340,11 @@ public List<AnnotatedAndMetadata<AnnotatedConstructor, JsonCreator.Mode>> getCon
         return result;
     }
 
+    @Override
+    public PotentialCreators getPotentialCreators() {
+        return _propCollector.getPotentialCreators();
+    }
+
     @Override
     public Object instantiateBean(boolean fixAccess) {
         AnnotatedConstructor ac = _classInfo.getDefaultConstructor();

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

@@ -91,6 +91,11 @@ public class POJOPropertiesCollector
 
     protected List<POJOPropertyBuilder> _creatorProperties;
 
+    /**
+     * @since 2.18
+     */
+    protected PotentialCreators _potentialCreators;
+
     /**
      * A set of "field renamings" that have been discovered, indicating
      * intended renaming of other accessors: key is the implicit original
@@ -218,6 +223,14 @@ public List<BeanPropertyDefinition> getProperties() {
         return new ArrayList<>(props.values());
     }
 
+    // @since 2.18
+    public PotentialCreators getPotentialCreators() {
+        if (!_collected) {
+            collectAll();
+        }
+        return _potentialCreators;
+    }
+
     public Map<Object, AnnotatedMember> getInjectables() {
         if (!_collected) {
             collectAll();
@@ -626,6 +639,8 @@ protected void _addFields(Map<String, POJOPropertyBuilder> props)
     // Completely rewritten in 2.18
     protected void _addCreators(Map<String, POJOPropertyBuilder> props)
     {
+        final PotentialCreators creators = new PotentialCreators();
+        _potentialCreators = creators;
         _creatorProperties = new ArrayList<>();
 
         // First, resolve explicit annotations for all potential Creators
@@ -648,35 +663,35 @@ protected void _addCreators(Map<String, POJOPropertyBuilder> props)
         _removeDisabledCreators(constructors);
         _removeDisabledCreators(factories);
 
-        final PotentialCreators collector = new PotentialCreators();
         // and use annotations to find explicitly chosen Creators
         if (_useAnnotations) { // can't have explicit ones without Annotation introspection
             // Start with Constructors as they have higher precedence:
-            _addExplicitlyAnnotatedCreators(collector, constructors, props, false);
+            _addExplicitlyAnnotatedCreators(creators, constructors, props, false);
             // followed by Factory methods (lower precedence)
-            _addExplicitlyAnnotatedCreators(collector, factories, props,
-                    collector.hasPropertiesBased());
+            _addExplicitlyAnnotatedCreators(creators, factories, props,
+                    creators.hasPropertiesBased());
         }
 
         // If no Explicitly annotated creators found, look
         // for ones with explicitly-named ({@code @JsonProperty}) parameters
-        if (!collector.hasPropertiesBased()) {
+        if (!creators.hasPropertiesBased()) {
             // only discover constructor Creators?
-            _addCreatorsWithAnnotatedNames(collector, constructors);
+            _addCreatorsWithAnnotatedNames(creators, constructors);
         }
 
         // But if no annotation-based Creators found, find/use canonical Creator
         // (JDK 17 Record/Scala/Kotlin)
-        if (!collector.hasPropertiesBased()) {
+        if (!creators.hasPropertiesBased()) {
             // for Records:
             if ((canonical != null) && constructors.contains(canonical)) {
                 constructors.remove(canonical);
-                collector.addPropertiesBased(_config, canonical, "canonical");
+                creators.setPropertiesBased(_config, canonical, "canonical");
             }
         }
 
-        // And finally add logical properties:
-        PotentialCreator primary = collector.propertiesBased;
+        // And finally add logical properties for the One Properties-based
+        // creator selected (if any):
+        PotentialCreator primary = creators.propertiesBased;
         if (primary != null) {
             _addCreatorParams(props, primary);
         }
@@ -766,10 +781,10 @@ private void _addExplicitlyAnnotatedCreators(PotentialCreators collector,
             if (propsBased) {
                 // Skipping done if we already got higher-precedence Creator
                 if (!skipPropsBased) {
-                    collector.addPropertiesBased(_config, ctor, "explicit");
+                    collector.setPropertiesBased(_config, ctor, "explicit");
                 }
             } else {
-                collector.addDelegating(ctor);
+                collector.addExplicitDelegating(ctor);
             }
         }
     }
@@ -788,7 +803,7 @@ private void _addCreatorsWithAnnotatedNames(PotentialCreators collector,
             }
             it.remove();
 
-            collector.addPropertiesBased(_config, ctor, "implicit");
+            collector.setPropertiesBased(_config, ctor, "implicit");
         }
     }
 

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

@@ -152,6 +152,10 @@ public String implicitNameSimple(int ix) {
         return (pn == null) ? null : pn.getSimpleName();
     }
 
+    public BeanPropertyDefinition[] propertyDefs() {
+        return propertyDefs;
+    }
+
     /*
     /**********************************************************************
     /* Misc other

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

@@ -11,7 +11,10 @@ public class PotentialCreators
      */
     public PotentialCreator propertiesBased;
 
-    public final List<PotentialCreator> delegating = new ArrayList<>();
+    private List<PotentialCreator> explicitDelegating;
+
+    private List<PotentialCreator> implicitDelegatingConstructors;
+    private List<PotentialCreator> implicitDelegatingFactories;
 
     public PotentialCreators()
     {
@@ -24,7 +27,7 @@ public PotentialCreators()
      */
 
     // desc -> "explicit", "implicit" etc
-    public void addPropertiesBased(MapperConfig<?> config, PotentialCreator ctor, String mode)
+    public void setPropertiesBased(MapperConfig<?> config, PotentialCreator ctor, String mode)
     {
         if (propertiesBased != null) {
             throw new IllegalArgumentException(String.format(
@@ -34,9 +37,19 @@ public void addPropertiesBased(MapperConfig<?> config, PotentialCreator ctor, St
         propertiesBased = ctor.introspectParamNames(config);
     }
 
-    public void addDelegating(PotentialCreator ctor)
+    public void addExplicitDelegating(PotentialCreator ctor)
+    {
+        if (explicitDelegating == null) {
+            explicitDelegating = new ArrayList<>();
+        }
+        explicitDelegating.add(ctor);
+    }
+
+    public void setImplicitDelegating(List<PotentialCreator> implicitConstructors,
+            List<PotentialCreator> implicitFactories)
     {
-        delegating.add(ctor);
+        implicitDelegatingConstructors = implicitConstructors;
+        implicitDelegatingFactories = implicitFactories;
     }
 
     /*
@@ -50,6 +63,18 @@ public boolean hasPropertiesBased() {
     }
 
     public boolean hasPropertiesBasedOrDelegating() {
-        return (propertiesBased != null) || !delegating.isEmpty();
+        return (propertiesBased != null) || (explicitDelegating != null && !explicitDelegating.isEmpty());
+    }
+
+    public List<PotentialCreator> getExplicitDelegating() {
+        return (explicitDelegating == null) ? Collections.emptyList() : explicitDelegating;
+    }
+
+    public List<PotentialCreator> getImplicitDelegatingFactories() {
+        return implicitDelegatingFactories;
+    }
+
+    public List<PotentialCreator> getImplicitDelegatingConstructors() {
+        return implicitDelegatingConstructors;
     }
 }