Fix #1998

Author: cowtowncoder

release-notes/VERSION-2.x

@@ -8,6 +8,9 @@ Project: jackson-databind
 
 #1565: Deserialization failure with Polymorphism using JsonTypeInfo `defaultImpl`,
   subtype as target
+#1998: Removing "type" attribute with Mixin not taken in account if
+  using ObjectMapper.copy()
+ (reported by SBKila@github)
 
 2.9.5 (26-Mar-2018)
 

src/main/java/com/fasterxml/jackson/databind/cfg/BaseSettings.java

@@ -147,6 +147,26 @@ public BaseSettings(ClassIntrospector ci, AnnotationIntrospector ai,
         _defaultBase64 = defaultBase64;
     }
 
+    /**
+     * Turns out we are not necessarily 100% stateless, alas, since {@link ClassIntrospector}
+     * typically has a cache. So this method is needed for deep copy() of Mapper.
+     *
+     * @since 2.9.6
+     */
+    public BaseSettings copy() {
+        return new BaseSettings(_classIntrospector.copy(),
+            _annotationIntrospector,
+            _propertyNamingStrategy,
+            _typeFactory,
+            _typeResolverBuilder,
+            _dateFormat,
+            _handlerInstantiator,
+            _locale,
+            _timeZone,
+            _defaultBase64);
+
+    }
+
     /*
     /**********************************************************
     /* Factory methods

src/main/java/com/fasterxml/jackson/databind/cfg/MapperConfigBase.java

@@ -134,13 +134,18 @@ protected MapperConfigBase(BaseSettings base,
     }
 
     /**
+     * Copy constructor usually called to make a copy for use by
+     * ObjectMapper that is copied.
+     *
      * @since 2.8
      */
     protected MapperConfigBase(MapperConfigBase<CFG,T> src,
             SimpleMixInResolver mixins, RootNameLookup rootNames,
             ConfigOverrides configOverrides)
     {
-        super(src);
+        // 18-Apr-2018, tatu: [databind#1898] need to force copying of `ClassIntrospector`
+        //    (to clear its cache) to avoid leakage
+        super(src, src._base.copy());
         _mixIns = mixins;
         _subtypeResolver = src._subtypeResolver;
         _rootNames = rootNames;

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

@@ -66,7 +66,12 @@ public BasicClassIntrospector() {
         // a small cache should go a long way here
         _cachedFCA = new LRUMap<JavaType,BasicBeanDescription>(16, 64);
     }
-    
+
+    @Override
+    public ClassIntrospector copy() {
+        return new BasicClassIntrospector();
+    }
+
     /*
     /**********************************************************
     /* Factory method impls

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

@@ -47,6 +47,13 @@ public interface MixInResolver
 
     protected ClassIntrospector() { }
 
+    /**
+     * Method that may be needed when `copy()`ing `ObjectMapper` instances.
+     *
+     * @since 2.9.6
+     */
+    public abstract ClassIntrospector copy();
+
     /*
     /**********************************************************
     /* Public API: factory methods

src/test/java/com/fasterxml/jackson/databind/mixins/MapperMixinsCopy1998Test.java

@@ -0,0 +1,128 @@
+package com.fasterxml.jackson.databind.mixins;
+
+import java.io.IOException;
+
+import com.fasterxml.jackson.annotation.*;
+
+import com.fasterxml.jackson.databind.*;
+
+public class MapperMixinsCopy1998Test extends BaseMapTest
+{
+    final static String FULLMODEL="{\"format\":\"1.0\",\"child\":{\"type\":\"CHILD_B\",\"name\":\"testB\"},\"notVisible\":\"should not be present\"}";
+    final static String EXPECTED="{\"format\":\"1.0\",\"child\":{\"name\":\"testB\"}}";
+
+    static class MyModelView { }
+
+    interface MixinConfig {
+        interface MyModelRoot {
+            @JsonView(MyModelView.class)
+            public String getFormat();
+
+            @JsonView(MyModelView.class)
+            public MyModelChildBase getChild();
+        }
+
+        @JsonTypeInfo(use = JsonTypeInfo.Id.NONE, include = JsonTypeInfo.As.EXISTING_PROPERTY)
+        interface MyModelChildBase {
+            @JsonView(MyModelView.class)
+            public String getName();
+        }
+
+    }
+
+    @JsonPropertyOrder({ "format", "child" })
+    static class MyModelRoot {
+        @JsonProperty
+        private String format = "1.0";
+
+        public String getFormat() {
+            return format;
+        }
+        @JsonProperty
+        private MyModelChildBase child;
+
+        public MyModelChildBase getChild() {
+            return child;
+        }
+
+        public void setChild(MyModelChildBase child) {
+            this.child = child;
+        }
+
+        @JsonProperty
+        private String notVisible = "should not be present";
+
+        public String getNotVisible() {
+            return notVisible;
+        }
+    }
+
+    @JsonTypeInfo(use = JsonTypeInfo.Id.NAME, property = "type")
+    @JsonSubTypes({
+            @JsonSubTypes.Type(value = MyChildA.class, name = "CHILD_A"),
+            @JsonSubTypes.Type(value = MyChildB.class, name = "CHILD_B")
+    })
+    abstract static class MyModelChildBase {
+        @JsonProperty
+        private String name;
+
+        public String getName() {
+            return name;
+        }
+
+        @JsonIgnore
+        public void setName(String name) {
+            this.name = name;
+        }
+    }
+
+    static class MyChildA extends MyModelChildBase {
+        public MyChildA(String name) {
+            setName(name);
+        }
+    }
+
+    static class MyChildB extends MyModelChildBase {
+        public MyChildB(String name) {
+            setName(name);
+        }
+    }
+
+    public void testB_KO() throws Exception
+    {
+        final ObjectMapper DEFAULT = defaultMapper();
+        MyModelRoot myModelInstance = new MyModelRoot();
+        myModelInstance.setChild(new MyChildB("testB"));
+
+        ObjectMapper myObjectMapper = DEFAULT.copy();
+
+        String postResult = getString(myModelInstance, myObjectMapper);
+        assertEquals(FULLMODEL, postResult);
+//        System.out.println("postResult: "+postResult);
+
+        myObjectMapper = DEFAULT.copy();
+//        myObjectMapper = defaultMapper();
+        myObjectMapper.addMixIn(MyModelRoot.class, MixinConfig.MyModelRoot.class)
+                .addMixIn(MyModelChildBase.class, MixinConfig.MyModelChildBase.class)
+                .disable(MapperFeature.DEFAULT_VIEW_INCLUSION)
+                .setConfig(myObjectMapper.getSerializationConfig().withView(MyModelView.class));
+
+        String result = getString(myModelInstance, myObjectMapper);
+System.out.println("result: "+result);
+        assertEquals(EXPECTED, result);
+
+    }
+
+    private String getString(MyModelRoot myModelInstance, ObjectMapper myObjectMapper) throws IOException {
+        return myObjectMapper.writerFor(MyModelRoot.class).writeValueAsString(myModelInstance);
+    }
+
+    private ObjectMapper defaultMapper()
+    {
+        return new ObjectMapper().setSerializationInclusion(JsonInclude.Include.NON_EMPTY)
+                .configure(SerializationFeature.WRITE_DATES_AS_TIMESTAMPS, false)
+                .configure(MapperFeature.ALLOW_COERCION_OF_SCALARS, false)
+                .configure(DeserializationFeature.FAIL_ON_UNKNOWN_PROPERTIES, true)
+            ;
+    }
+}