minor refactoring

src/main/java/com/fasterxml/jackson/databind/ser/std/ToStringSerializer.java

@@ -1,27 +1,18 @@
 package com.fasterxml.jackson.databind.ser.std;
 
-import java.io.IOException;
-import java.lang.reflect.Type;
-
-import com.fasterxml.jackson.core.*;
-import com.fasterxml.jackson.core.type.WritableTypeId;
-import com.fasterxml.jackson.databind.JavaType;
-import com.fasterxml.jackson.databind.JsonMappingException;
-import com.fasterxml.jackson.databind.JsonNode;
-import com.fasterxml.jackson.databind.SerializerProvider;
 import com.fasterxml.jackson.databind.annotation.JacksonStdImpl;
-import com.fasterxml.jackson.databind.jsonFormatVisitors.JsonFormatVisitorWrapper;
-import com.fasterxml.jackson.databind.jsontype.TypeSerializer;
 
 /**
  * Simple general purpose serializer, useful for any
  * type for which {@link Object#toString} returns the desired JSON
  * value.
+ *<p>
+ * Since 2.10 extends {@link ToStringSerializerBase}
  */
 @JacksonStdImpl
 @SuppressWarnings("serial")
 public class ToStringSerializer
-    extends StdSerializer<Object>
+    extends ToStringSerializerBase
 {
     /**
      * Singleton instance to use.
@@ -39,56 +30,16 @@ public class ToStringSerializer
     public ToStringSerializer() { super(Object.class); }
 
     /**
-     * Sometimes it may actually make sense to retain actual handled type, so...
+     * Sometimes it may actually make sense to retain actual handled type.
      * 
      * @since 2.5
      */
     public ToStringSerializer(Class<?> handledType) {
-        super(handledType, false);
-    }
-
-    @Override
-    public boolean isEmpty(SerializerProvider prov, Object value) {
-        return value.toString().isEmpty();
-    }
-
-    @Override
-    public void serialize(Object value, JsonGenerator gen, SerializerProvider provider)
-        throws IOException
-    {
-        gen.writeString(value.toString());
-    }
-
-    /* 01-Mar-2011, tatu: We were serializing as "raw" String; but generally that
-     *   is not what we want, since lack of type information would imply real
-     *   String type.
-     */
-    /**
-     * Default implementation will write type prefix, call regular serialization
-     * method (since assumption is that value itself does not need JSON
-     * Array or Object start/end markers), and then write type suffix.
-     * This should work for most cases; some sub-classes may want to
-     * change this behavior.
-     */
-    @Override
-    public void serializeWithType(Object value, JsonGenerator g, SerializerProvider provider,
-            TypeSerializer typeSer)
-        throws IOException
-    {
-        WritableTypeId typeIdDef = typeSer.writeTypePrefix(g,
-                typeSer.typeId(value, JsonToken.VALUE_STRING));
-        serialize(value, g, provider);
-        typeSer.writeTypeSuffix(g, typeIdDef);
-    }
-
-    @Override
-    public JsonNode getSchema(SerializerProvider provider, Type typeHint) throws JsonMappingException {
-        return createSchemaNode("string", true);
+        super(handledType);
     }
 
     @Override
-    public void acceptJsonFormatVisitor(JsonFormatVisitorWrapper visitor, JavaType typeHint) throws JsonMappingException
-    {
-        visitStringFormat(visitor, typeHint);
+    public final String valueToString(Object value) {
+        return value.toString();
     }
 }

src/main/java/com/fasterxml/jackson/databind/ser/std/ToStringSerializerBase.java

@@ -0,0 +1,74 @@
+package com.fasterxml.jackson.databind.ser.std;
+
+import java.io.IOException;
+import java.lang.reflect.Type;
+
+import com.fasterxml.jackson.core.JsonGenerator;
+import com.fasterxml.jackson.core.JsonToken;
+import com.fasterxml.jackson.core.type.WritableTypeId;
+import com.fasterxml.jackson.databind.JavaType;
+import com.fasterxml.jackson.databind.JsonMappingException;
+import com.fasterxml.jackson.databind.JsonNode;
+import com.fasterxml.jackson.databind.SerializerProvider;
+import com.fasterxml.jackson.databind.jsonFormatVisitors.JsonFormatVisitorWrapper;
+import com.fasterxml.jackson.databind.jsontype.TypeSerializer;
+
+/**
+ * Intermediate base class that serves as base for standard {@link ToStringSerializer}
+ * as well as for custom subtypes that want to add processing for converting from
+ * value to output into its {@code String} representation (whereas standard version
+ * simply calls value object's {@code toString()} method).
+ *
+ * @since 2.10
+ */
+@SuppressWarnings("serial")
+public abstract class ToStringSerializerBase
+    extends StdSerializer<Object>
+{
+    public ToStringSerializerBase(Class<?> handledType) {
+        super(handledType, false);
+    }
+
+    @Override
+    public boolean isEmpty(SerializerProvider prov, Object value) {
+        return valueToString(value).isEmpty();
+    }
+
+    @Override
+    public void serialize(Object value, JsonGenerator gen, SerializerProvider provider)
+        throws IOException
+    {
+        gen.writeString(valueToString(value));
+    }
+
+    /**
+     * Default implementation will write type prefix, call regular serialization
+     * method (since assumption is that value itself does not need JSON
+     * Array or Object start/end markers), and then write type suffix.
+     * This should work for most cases; some sub-classes may want to
+     * change this behavior.
+     */
+    @Override
+    public void serializeWithType(Object value, JsonGenerator g, SerializerProvider provider,
+            TypeSerializer typeSer)
+        throws IOException
+    {
+        WritableTypeId typeIdDef = typeSer.writeTypePrefix(g,
+                typeSer.typeId(value, JsonToken.VALUE_STRING));
+        serialize(value, g, provider);
+        typeSer.writeTypeSuffix(g, typeIdDef);
+    }
+
+    @Override
+    public JsonNode getSchema(SerializerProvider provider, Type typeHint) throws JsonMappingException {
+        return createSchemaNode("string", true);
+    }
+
+    @Override
+    public void acceptJsonFormatVisitor(JsonFormatVisitorWrapper visitor, JavaType typeHint) throws JsonMappingException
+    {
+        visitStringFormat(visitor, typeHint);
+    }
+
+    public abstract String valueToString(Object value);
+}