Merge datetime#376 (from 2.21 branch) (minimal, no tests) (#5400)

Author: cowtowncoder

src/main/java/tools/jackson/databind/ext/javatime/deser/InstantDeserializer.java

@@ -206,37 +206,27 @@ protected InstantDeserializer(InstantDeserializer<T> base,
         _readTimestampsAsNanosOverride = readTimestampsAsNanosOverride;
     }
 
-    /*
-    @SuppressWarnings("unchecked")
-    protected InstantDeserializer(InstantDeserializer<T> base,
-            DatatypeFeatures features)
-    {
-        super((Class<T>) base.handledType(), base._formatter);
-        parsedToValue = base.parsedToValue;
-        fromMilliseconds = base.fromMilliseconds;
-        fromNanoseconds = base.fromNanoseconds;
-        adjust = base.adjust;
-        replaceZeroOffsetAsZ = base.replaceZeroOffsetAsZ;
-        _adjustToContextTZOverride = base._adjustToContextTZOverride;
-        _readTimestampsAsNanosOverride = base._readTimestampsAsNanosOverride;
-    }
-    */
-
+    /**
+     * NOTE: {@code public} since 2.21 / 3.1
+     */
     @Override
-    protected InstantDeserializer<T> withDateFormat(DateTimeFormatter dtf) {
+    public InstantDeserializer<T> withDateFormat(DateTimeFormatter dtf) {
         if (dtf == _formatter) {
             return this;
         }
         return new InstantDeserializer<>(this, dtf);
     }
 
+    /**
+     * NOTE: {@code public} since 2.21 / 3.1
+     */
     @Override
-    protected InstantDeserializer<T> withLeniency(Boolean leniency) {
+    public InstantDeserializer<T> withLeniency(Boolean leniency) {
         return new InstantDeserializer<>(this, _formatter, leniency);
     }
 
     @SuppressWarnings("unchecked")
-    @Override // @since 2.12.1
+    @Override
     protected JSR310DateTimeDeserializerBase<?> _withFormatOverrides(DeserializationContext ctxt,
             BeanProperty property, JsonFormat.Value formatOverrides)
     {

src/main/java/tools/jackson/databind/ext/javatime/ser/OffsetDateTimeSerializer.java

@@ -27,6 +27,27 @@ protected OffsetDateTimeSerializer(OffsetDateTimeSerializer base,
         super(base, formatter, useTimestamp, useNanoseconds, shape);
     }
 
+    /**
+     * Method for constructing a new {@code OffsetDateTimeSerializer} with settings
+     * of this serializer but with custom {@link DateTimeFormatter} overrides.
+     * Commonly used on {@code INSTANCE} like so:
+     *<pre>
+     *  DateTimeFormatter dtf = new DateTimeFormatterBuilder()
+     *          .append(DateTimeFormatter.ISO_LOCAL_DATE)
+     *          .appendLiteral('T')
+     *          // and so on
+     *          .toFormatter();
+     *  OffsetDateTimeSerializer ser = OffsetDateTimeSerializer.INSTANCE
+     *          .withFormatter(dtf);
+     *  // register via Module
+     *</pre>
+     *
+     * @since 2.21 / 3.1
+     */
+    public OffsetDateTimeSerializer withFormatter(DateTimeFormatter formatter)     {
+        return new OffsetDateTimeSerializer(this, _useTimestamp, formatter, _shape);
+    }
+
     @Override
     protected JSR310FormattedSerializerBase<?> withFormat(DateTimeFormatter formatter,
             Boolean useTimestamp,