Warnings cleanup, minor refactoring of XMLGregorianCalendarSerializer

16 files changed, 93 insertions, 42 deletions

diff --git a/src/main/java/com/fasterxml/jackson/databind/ext/CoreXMLSerializers.java b/src/main/java/com/fasterxml/jackson/databind/ext/CoreXMLSerializers.java
index a9460fbb8..d44fa4b67 100644
--- a/src/main/java/com/fasterxml/jackson/databind/ext/CoreXMLSerializers.java
+++ b/src/main/java/com/fasterxml/jackson/databind/ext/CoreXMLSerializers.java
@@ -1,16 +1,17 @@
 package com.fasterxml.jackson.databind.ext;
 
 import java.io.IOException;
-import java.lang.reflect.Type;
+import java.util.Calendar;
 
 import javax.xml.datatype.Duration;
 import javax.xml.datatype.XMLGregorianCalendar;
 import javax.xml.namespace.QName;
 
 import com.fasterxml.jackson.core.*;
-
 import com.fasterxml.jackson.databind.*;
 import com.fasterxml.jackson.databind.jsonFormatVisitors.JsonFormatVisitorWrapper;
+import com.fasterxml.jackson.databind.jsontype.TypeSerializer;
+import com.fasterxml.jackson.databind.ser.ContextualSerializer;
 import com.fasterxml.jackson.databind.ser.Serializers;
 import com.fasterxml.jackson.databind.ser.std.CalendarSerializer;
 import com.fasterxml.jackson.databind.ser.std.StdSerializer;
@@ -36,31 +37,76 @@ public class CoreXMLSerializers extends Serializers.Base
             return ToStringSerializer.instance;
         }
         if (XMLGregorianCalendar.class.isAssignableFrom(raw)) {
-            return new XMLGregorianCalendarSerializer();
+            return XMLGregorianCalendarSerializer.instance;
         }
         return null;
     }
 
-    public static class XMLGregorianCalendarSerializer extends StdSerializer<XMLGregorianCalendar>
+    @SuppressWarnings("serial")
+    public static class XMLGregorianCalendarSerializer
+        extends StdSerializer<XMLGregorianCalendar>
+        implements ContextualSerializer
     {
+        final static XMLGregorianCalendarSerializer instance = new XMLGregorianCalendarSerializer();
+
+        final JsonSerializer<Object> _delegate;
+        
         public XMLGregorianCalendarSerializer() {
+            this(CalendarSerializer.instance);
+        }
+
+        @SuppressWarnings("unchecked")
+        protected XMLGregorianCalendarSerializer(JsonSerializer<?> del) {
             super(XMLGregorianCalendar.class);
+            _delegate = (JsonSerializer<Object>) del;
+        }
+
+        @Override
+        public JsonSerializer<?> getDelegatee() {
+            return _delegate;
+        }
+
+        @Deprecated
+        @Override
+        public boolean isEmpty(XMLGregorianCalendar value) {
+            return _delegate.isEmpty(_convert(value));
+        }
+
+        @Override
+        public boolean isEmpty(SerializerProvider provider, XMLGregorianCalendar value) {
+            return _delegate.isEmpty(provider, _convert(value));
         }
 
         @Override
         public void serialize(XMLGregorianCalendar value, JsonGenerator jgen, SerializerProvider provider)
-                throws IOException, JsonGenerationException {
-            CalendarSerializer.instance.serialize(value.toGregorianCalendar(), jgen, provider);
+                throws IOException {
+            _delegate.serialize(_convert(value), jgen, provider);
         }
-        
+
         @Override
-        public JsonNode getSchema(SerializerProvider provider, Type typeHint) throws JsonMappingException {
-            return CalendarSerializer.instance.getSchema(provider, typeHint);
+        public void serializeWithType(XMLGregorianCalendar value, JsonGenerator gen, SerializerProvider provider,
+                TypeSerializer typeSer) throws IOException
+        {
+            _delegate.serializeWithType(_convert(value), gen, provider, typeSer);
         }
 
         @Override
         public void acceptJsonFormatVisitor(JsonFormatVisitorWrapper visitor, JavaType typeHint) throws JsonMappingException {
-            CalendarSerializer.instance.acceptJsonFormatVisitor(visitor, null);
+            _delegate.acceptJsonFormatVisitor(visitor, null);
+        }
+
+        @Override
+        public JsonSerializer<?> createContextual(SerializerProvider prov, BeanProperty property)
+                throws JsonMappingException {
+            JsonSerializer<?> ser = prov.handlePrimaryContextualization(_delegate, property);
+            if (ser != _delegate) {
+                return new XMLGregorianCalendarSerializer(ser);
+            }
+            return this;
+        }
+
+        protected Calendar _convert(XMLGregorianCalendar input) {
+            return (input == null) ? null : input.toGregorianCalendar();
         }
     }
 }
diff --git a/src/main/java/com/fasterxml/jackson/databind/ext/DOMSerializer.java b/src/main/java/com/fasterxml/jackson/databind/ext/DOMSerializer.java
index 90cb1dd90..9095b32c1 100644
--- a/src/main/java/com/fasterxml/jackson/databind/ext/DOMSerializer.java
+++ b/src/main/java/com/fasterxml/jackson/databind/ext/DOMSerializer.java
@@ -1,13 +1,13 @@
 package com.fasterxml.jackson.databind.ext;
 
 import java.io.IOException;
+
 import org.w3c.dom.Node;
 import  org.w3c.dom.bootstrap.DOMImplementationRegistry;
 import  org.w3c.dom.ls.DOMImplementationLS;
 import  org.w3c.dom.ls.LSSerializer;
 
 import com.fasterxml.jackson.core.*;
-
 import com.fasterxml.jackson.databind.JavaType;
 import com.fasterxml.jackson.databind.JsonMappingException;
 import com.fasterxml.jackson.databind.JsonNode;
@@ -15,6 +15,7 @@ import com.fasterxml.jackson.databind.SerializerProvider;
 import com.fasterxml.jackson.databind.jsonFormatVisitors.JsonFormatVisitorWrapper;
 import com.fasterxml.jackson.databind.ser.std.StdSerializer;
 
+@SuppressWarnings("serial")
 public class DOMSerializer extends StdSerializer<Node>
 {
     protected final DOMImplementationLS _domImpl;
diff --git a/src/main/java/com/fasterxml/jackson/databind/ser/ContainerSerializer.java b/src/main/java/com/fasterxml/jackson/databind/ser/ContainerSerializer.java
index 1da6d88ee..ac0820096 100644
--- a/src/main/java/com/fasterxml/jackson/databind/ser/ContainerSerializer.java
+++ b/src/main/java/com/fasterxml/jackson/databind/ser/ContainerSerializer.java
@@ -12,6 +12,7 @@ import com.fasterxml.jackson.databind.ser.std.StdSerializer;
  * etc) and {@link java.util.Map}s and iterable things
  * ({@link java.util.Iterator}s).
  */
+@SuppressWarnings("serial")
 public abstract class ContainerSerializer<T>
     extends StdSerializer<T>
 {
diff --git a/src/main/java/com/fasterxml/jackson/databind/ser/impl/FailingSerializer.java b/src/main/java/com/fasterxml/jackson/databind/ser/impl/FailingSerializer.java
index fafa13d2b..80d96b38b 100644
--- a/src/main/java/com/fasterxml/jackson/databind/ser/impl/FailingSerializer.java
+++ b/src/main/java/com/fasterxml/jackson/databind/ser/impl/FailingSerializer.java
@@ -4,7 +4,6 @@ import java.io.IOException;
 import java.lang.reflect.Type;
 
 import com.fasterxml.jackson.core.*;
-
 import com.fasterxml.jackson.databind.JavaType;
 import com.fasterxml.jackson.databind.JsonMappingException;
 import com.fasterxml.jackson.databind.JsonNode;
@@ -19,10 +18,11 @@ import com.fasterxml.jackson.databind.ser.std.StdSerializer;
  * as well as for catching unintended usage (like trying to use null
  * as Map/Object key).
  */
-public final class FailingSerializer
+@SuppressWarnings("serial")
+public class FailingSerializer
     extends StdSerializer<Object>
 {
-    final String _msg;
+    protected final String _msg;
     
     public FailingSerializer(String msg) {
         super(Object.class);
@@ -30,16 +30,13 @@ public final class FailingSerializer
     }
     
     @Override
-    public void serialize(Object value, JsonGenerator jgen, SerializerProvider provider)
-        throws IOException, JsonGenerationException
+    public void serialize(Object value, JsonGenerator jgen, SerializerProvider provider) throws IOException
     {
         throw new JsonGenerationException(_msg);
     }
 
     @Override
-    public JsonNode getSchema(SerializerProvider provider, Type typeHint)
-        throws JsonMappingException
-    {
+    public JsonNode getSchema(SerializerProvider provider, Type typeHint) throws JsonMappingException {
         return null;
     }
     
diff --git a/src/main/java/com/fasterxml/jackson/databind/ser/impl/IndexedListSerializer.java b/src/main/java/com/fasterxml/jackson/databind/ser/impl/IndexedListSerializer.java
index 417db7991..a7ff0f50f 100644
--- a/src/main/java/com/fasterxml/jackson/databind/ser/impl/IndexedListSerializer.java
+++ b/src/main/java/com/fasterxml/jackson/databind/ser/impl/IndexedListSerializer.java
@@ -20,6 +20,8 @@ import com.fasterxml.jackson.databind.ser.std.AsArraySerializerBase;
 public final class IndexedListSerializer
     extends AsArraySerializerBase<List<?>>
 {
+    private static final long serialVersionUID = 1L;
+
     public IndexedListSerializer(JavaType elemType, boolean staticTyping, TypeSerializer vts,
             BeanProperty property, JsonSerializer<Object> valueSerializer)
     {
diff --git a/src/main/java/com/fasterxml/jackson/databind/ser/std/ArraySerializerBase.java b/src/main/java/com/fasterxml/jackson/databind/ser/std/ArraySerializerBase.java
index 2968db186..bcc4f91b2 100644
--- a/src/main/java/com/fasterxml/jackson/databind/ser/std/ArraySerializerBase.java
+++ b/src/main/java/com/fasterxml/jackson/databind/ser/std/ArraySerializerBase.java
@@ -3,7 +3,6 @@ package com.fasterxml.jackson.databind.ser.std;
 import java.io.IOException;
 
 import com.fasterxml.jackson.core.*;
-
 import com.fasterxml.jackson.databind.*;
 import com.fasterxml.jackson.databind.jsontype.TypeSerializer;
 import com.fasterxml.jackson.databind.ser.*;
@@ -14,6 +13,7 @@ import com.fasterxml.jackson.databind.ser.*;
  * 
  * @param <T> Type of arrays serializer handles
  */
+@SuppressWarnings("serial")
 public abstract class ArraySerializerBase<T>
     extends ContainerSerializer<T>
 {
diff --git a/src/main/java/com/fasterxml/jackson/databind/ser/std/AsArraySerializerBase.java b/src/main/java/com/fasterxml/jackson/databind/ser/std/AsArraySerializerBase.java
index 91a6510c8..7ae5fc98f 100644
--- a/src/main/java/com/fasterxml/jackson/databind/ser/std/AsArraySerializerBase.java
+++ b/src/main/java/com/fasterxml/jackson/databind/ser/std/AsArraySerializerBase.java
@@ -20,6 +20,7 @@ import com.fasterxml.jackson.databind.ser.impl.PropertySerializerMap;
  * arrays; typically serializers used for {@link java.util.Collection}
  * and array types.
  */
+@SuppressWarnings("serial")
 public abstract class AsArraySerializerBase<T>
     extends ContainerSerializer<T>
     implements ContextualSerializer
diff --git a/src/main/java/com/fasterxml/jackson/databind/ser/std/CollectionSerializer.java b/src/main/java/com/fasterxml/jackson/databind/ser/std/CollectionSerializer.java
index bdbcbc39d..1b32c344b 100644
--- a/src/main/java/com/fasterxml/jackson/databind/ser/std/CollectionSerializer.java
+++ b/src/main/java/com/fasterxml/jackson/databind/ser/std/CollectionSerializer.java
@@ -24,6 +24,8 @@ import com.fasterxml.jackson.databind.ser.impl.PropertySerializerMap;
 public class CollectionSerializer
     extends AsArraySerializerBase<Collection<?>>
 {
+    private static final long serialVersionUID = 1L;
+
     /*
     /**********************************************************
     /* Life-cycle
diff --git a/src/main/java/com/fasterxml/jackson/databind/ser/std/DateSerializer.java b/src/main/java/com/fasterxml/jackson/databind/ser/std/DateSerializer.java
index 7a484483a..c22f2c580 100644
--- a/src/main/java/com/fasterxml/jackson/databind/ser/std/DateSerializer.java
+++ b/src/main/java/com/fasterxml/jackson/databind/ser/std/DateSerializer.java
@@ -5,7 +5,6 @@ import java.text.DateFormat;
 import java.util.*;
 
 import com.fasterxml.jackson.core.*;
-
 import com.fasterxml.jackson.databind.*;
 import com.fasterxml.jackson.databind.annotation.JacksonStdImpl;
 
@@ -14,6 +13,7 @@ import com.fasterxml.jackson.databind.annotation.JacksonStdImpl;
  * potentially more readable Strings.
  */
 @JacksonStdImpl
+@SuppressWarnings("serial")
 public class DateSerializer
     extends DateTimeSerializerBase<Date>
 {
diff --git a/src/main/java/com/fasterxml/jackson/databind/ser/std/DateTimeSerializerBase.java b/src/main/java/com/fasterxml/jackson/databind/ser/std/DateTimeSerializerBase.java
index 2825a0a78..eb8464788 100644
--- a/src/main/java/com/fasterxml/jackson/databind/ser/std/DateTimeSerializerBase.java
+++ b/src/main/java/com/fasterxml/jackson/databind/ser/std/DateTimeSerializerBase.java
@@ -17,6 +17,7 @@ import com.fasterxml.jackson.databind.jsonFormatVisitors.*;
 import com.fasterxml.jackson.databind.ser.ContextualSerializer;
 import com.fasterxml.jackson.databind.util.StdDateFormat;
 
+@SuppressWarnings("serial")
 public abstract class DateTimeSerializerBase<T>
     extends StdScalarSerializer<T>
     implements ContextualSerializer
diff --git a/src/main/java/com/fasterxml/jackson/databind/ser/std/FileSerializer.java b/src/main/java/com/fasterxml/jackson/databind/ser/std/FileSerializer.java
index 8db1757c3..f587729cd 100644
--- a/src/main/java/com/fasterxml/jackson/databind/ser/std/FileSerializer.java
+++ b/src/main/java/com/fasterxml/jackson/databind/ser/std/FileSerializer.java
@@ -4,7 +4,6 @@ import java.io.File;
 import java.io.IOException;
 import java.lang.reflect.Type;
 
-import com.fasterxml.jackson.core.JsonGenerationException;
 import com.fasterxml.jackson.core.JsonGenerator;
 import com.fasterxml.jackson.databind.JavaType;
 import com.fasterxml.jackson.databind.JsonMappingException;
@@ -16,21 +15,19 @@ import com.fasterxml.jackson.databind.jsonFormatVisitors.JsonFormatVisitorWrappe
  * For now, File objects get serialized by just outputting
  * absolute (but not canonical) name as String value
  */
+@SuppressWarnings("serial")
 public class FileSerializer
     extends StdScalarSerializer<File>
 {
     public FileSerializer() { super(File.class); }
 
     @Override
-    public void serialize(File value, JsonGenerator jgen, SerializerProvider provider)
-        throws IOException, JsonGenerationException
-    {
+    public void serialize(File value, JsonGenerator jgen, SerializerProvider provider) throws IOException {
         jgen.writeString(value.getAbsolutePath());
     }
 
     @Override
-    public JsonNode getSchema(SerializerProvider provider, Type typeHint)
-    {
+    public JsonNode getSchema(SerializerProvider provider, Type typeHint) {
         return createSchemaNode("string", true);
     }
     
diff --git a/src/main/java/com/fasterxml/jackson/databind/ser/std/NumberSerializers.java b/src/main/java/com/fasterxml/jackson/databind/ser/std/NumberSerializers.java
index e368b37b3..ca9bbc1fc 100644
--- a/src/main/java/com/fasterxml/jackson/databind/ser/std/NumberSerializers.java
+++ b/src/main/java/com/fasterxml/jackson/databind/ser/std/NumberSerializers.java
@@ -18,6 +18,7 @@ import com.fasterxml.jackson.databind.ser.ContextualSerializer;
 /**
  * Container class for serializers used for handling standard JDK-provided types.
  */
+@SuppressWarnings("serial")
 public class NumberSerializers
 {
     protected NumberSerializers() { }
diff --git a/src/main/java/com/fasterxml/jackson/databind/ser/std/StdArraySerializers.java b/src/main/java/com/fasterxml/jackson/databind/ser/std/StdArraySerializers.java
index 19f7929f8..798292059 100644
--- a/src/main/java/com/fasterxml/jackson/databind/ser/std/StdArraySerializers.java
+++ b/src/main/java/com/fasterxml/jackson/databind/ser/std/StdArraySerializers.java
@@ -19,6 +19,7 @@ import com.fasterxml.jackson.databind.type.TypeFactory;
  * Dummy container class to group standard homogenous array serializer implementations
  * (primitive arrays and String array).
  */
+@SuppressWarnings("serial")
 public class StdArraySerializers
 {
     protected final static HashMap<String, JsonSerializer<?>> _arraySerializers =
@@ -81,7 +82,7 @@ public class StdArraySerializers
      */
 
     @JacksonStdImpl
-    public final static class BooleanArraySerializer extends ArraySerializerBase<boolean[]>
+    public static class BooleanArraySerializer extends ArraySerializerBase<boolean[]>
     {
         // as above, assuming no one re-defines primitive/wrapper types
         private final static JavaType VALUE_TYPE = TypeFactory.defaultInstance().uncheckedSimpleType(Boolean.class);
@@ -169,7 +170,7 @@ public class StdArraySerializers
      * NOTE: since it is NOT serialized as an array, can not use AsArraySerializer as base
      */
     @JacksonStdImpl
-    public final static class ByteArraySerializer extends StdSerializer<byte[]>
+    public static class ByteArraySerializer extends StdSerializer<byte[]>
     {
         public ByteArraySerializer() {
             super(byte[].class);
@@ -221,7 +222,7 @@ public class StdArraySerializers
     }
 
     @JacksonStdImpl
-    public final static class ShortArraySerializer extends TypedPrimitiveArraySerializer<short[]>
+    public static class ShortArraySerializer extends TypedPrimitiveArraySerializer<short[]>
     {
         // as above, assuming no one re-defines primitive/wrapper types
         private final static JavaType VALUE_TYPE = TypeFactory.defaultInstance().uncheckedSimpleType(Short.TYPE);
@@ -317,7 +318,7 @@ public class StdArraySerializers
      * NOTE: since it is NOT serialized as an array, can not use AsArraySerializer as base
      */
     @JacksonStdImpl
-    public final static class CharArraySerializer extends StdSerializer<char[]>
+    public static class CharArraySerializer extends StdSerializer<char[]>
     {
         public CharArraySerializer() { super(char[].class); }
         
@@ -388,7 +389,7 @@ public class StdArraySerializers
     }
 
     @JacksonStdImpl
-    public final static class IntArraySerializer extends ArraySerializerBase<int[]>
+    public static class IntArraySerializer extends ArraySerializerBase<int[]>
     {
         // as above, assuming no one re-defines primitive/wrapper types
         private final static JavaType VALUE_TYPE = TypeFactory.defaultInstance().uncheckedSimpleType(Integer.TYPE);
@@ -465,7 +466,7 @@ public class StdArraySerializers
     }
 
     @JacksonStdImpl
-    public final static class LongArraySerializer extends TypedPrimitiveArraySerializer<long[]>
+    public static class LongArraySerializer extends TypedPrimitiveArraySerializer<long[]>
     {
         // as above, assuming no one re-defines primitive/wrapper types
         private final static JavaType VALUE_TYPE = TypeFactory.defaultInstance().uncheckedSimpleType(Long.TYPE);
@@ -554,7 +555,7 @@ public class StdArraySerializers
     }
 
     @JacksonStdImpl
-    public final static class FloatArraySerializer extends TypedPrimitiveArraySerializer<float[]>
+    public static class FloatArraySerializer extends TypedPrimitiveArraySerializer<float[]>
     {
         // as above, assuming no one re-defines primitive/wrapper types
         private final static JavaType VALUE_TYPE = TypeFactory.defaultInstance().uncheckedSimpleType(Float.TYPE);
@@ -641,7 +642,7 @@ public class StdArraySerializers
     }
 
     @JacksonStdImpl
-    public final static class DoubleArraySerializer extends ArraySerializerBase<double[]>
+    public static class DoubleArraySerializer extends ArraySerializerBase<double[]>
     {
         // as above, assuming no one re-defines primitive/wrapper types
         private final static JavaType VALUE_TYPE = TypeFactory.defaultInstance().uncheckedSimpleType(Double.TYPE);
diff --git a/src/main/java/com/fasterxml/jackson/databind/ser/std/StdDelegatingSerializer.java b/src/main/java/com/fasterxml/jackson/databind/ser/std/StdDelegatingSerializer.java
index a9e86ab57..0b435ead1 100644
--- a/src/main/java/com/fasterxml/jackson/databind/ser/std/StdDelegatingSerializer.java
+++ b/src/main/java/com/fasterxml/jackson/databind/ser/std/StdDelegatingSerializer.java
@@ -1,7 +1,6 @@
 package com.fasterxml.jackson.databind.ser.std;
 
 import com.fasterxml.jackson.core.JsonGenerator;
-
 import com.fasterxml.jackson.databind.*;
 import com.fasterxml.jackson.databind.jsonFormatVisitors.JsonFormatVisitable;
 import com.fasterxml.jackson.databind.jsonFormatVisitors.JsonFormatVisitorWrapper;
@@ -24,6 +23,7 @@ import java.lang.reflect.Type;
  *
  * @since 2.1
  */
+@SuppressWarnings("serial")
 public class StdDelegatingSerializer
     extends StdSerializer<Object>
     implements ContextualSerializer, ResolvableSerializer,
diff --git a/src/main/java/com/fasterxml/jackson/databind/ser/std/StdJdkSerializers.java b/src/main/java/com/fasterxml/jackson/databind/ser/std/StdJdkSerializers.java
index 13ae3e3e6..f8f446844 100644
--- a/src/main/java/com/fasterxml/jackson/databind/ser/std/StdJdkSerializers.java
+++ b/src/main/java/com/fasterxml/jackson/databind/ser/std/StdJdkSerializers.java
@@ -6,7 +6,6 @@ import java.util.*;
 import java.util.concurrent.atomic.*;
 
 import com.fasterxml.jackson.core.*;
-
 import com.fasterxml.jackson.databind.*;
 import com.fasterxml.jackson.databind.jsonFormatVisitors.JsonFormatVisitorWrapper;
 import com.fasterxml.jackson.databind.jsonFormatVisitors.JsonIntegerFormatVisitor;
@@ -17,6 +16,7 @@ import com.fasterxml.jackson.databind.ser.BasicSerializerFactory;
  * are serializer as scalars; some using basic {@link ToStringSerializer},
  * others explicit serializers.
  */
+@SuppressWarnings("serial")
 public class StdJdkSerializers
 {
     /**
@@ -64,7 +64,7 @@ public class StdJdkSerializers
     /**********************************************************
      */
 
-    public final static class AtomicBooleanSerializer
+    public static class AtomicBooleanSerializer
         extends StdScalarSerializer<AtomicBoolean>
     {
         public AtomicBooleanSerializer() { super(AtomicBoolean.class, false); }
@@ -85,7 +85,7 @@ public class StdJdkSerializers
         }
     }
     
-    public final static class AtomicIntegerSerializer
+    public static class AtomicIntegerSerializer
         extends StdScalarSerializer<AtomicInteger>
     {
         public AtomicIntegerSerializer() { super(AtomicInteger.class, false); }
@@ -110,7 +110,7 @@ public class StdJdkSerializers
         }
     }
 
-    public final static class AtomicLongSerializer
+    public static class AtomicLongSerializer
         extends StdScalarSerializer<AtomicLong>
     {
         public AtomicLongSerializer() { super(AtomicLong.class, false); }
@@ -135,8 +135,8 @@ public class StdJdkSerializers
             }
         }
     }
-    
-    public final static class AtomicReferenceSerializer
+
+    public static class AtomicReferenceSerializer
         extends StdSerializer<AtomicReference<?>>
     {
         public AtomicReferenceSerializer() { super(AtomicReference.class, false); }
diff --git a/src/main/java/com/fasterxml/jackson/databind/ser/std/StdKeySerializers.java b/src/main/java/com/fasterxml/jackson/databind/ser/std/StdKeySerializers.java
index 33ea2acb6..515c08fc6 100644
--- a/src/main/java/com/fasterxml/jackson/databind/ser/std/StdKeySerializers.java
+++ b/src/main/java/com/fasterxml/jackson/databind/ser/std/StdKeySerializers.java
@@ -7,6 +7,7 @@ import java.util.Date;
 import com.fasterxml.jackson.core.*;
 import com.fasterxml.jackson.databind.*;
 
+@SuppressWarnings("serial")
 public class StdKeySerializers
 {
     protected final static JsonSerializer<Object> DEFAULT_KEY_SERIALIZER = new StdKeySerializer();