Fix #296: add null checks for type serialization for 7 types

Author: cowtowncoder

datetime/src/main/java/com/fasterxml/jackson/datatype/jsr310/ser/MonthDaySerializer.java

@@ -81,7 +81,8 @@ public void serializeWithType(MonthDay value, JsonGenerator g,
         WritableTypeId typeIdDef = typeSer.writeTypePrefix(g,
                 typeSer.typeId(value, serializationShape(provider)));
         // need to write out to avoid double-writing array markers
-        if (typeIdDef.valueShape == JsonToken.START_ARRAY) {
+        if ((typeIdDef != null)
+                && typeIdDef.valueShape == JsonToken.START_ARRAY) {
             _serializeAsArrayContents(value, g, provider);
         } else {
             g.writeString((_formatter == null) ? value.toString() : value.format(_formatter));

datetime/src/main/java/com/fasterxml/jackson/datatype/jsr310/ser/OffsetTimeSerializer.java

@@ -79,7 +79,8 @@ public void serializeWithType(OffsetTime value, JsonGenerator g, SerializerProvi
         WritableTypeId typeIdDef = typeSer.writeTypePrefix(g,
                 typeSer.typeId(value, serializationShape(provider)));
         // need to write out to avoid double-writing array markers
-        if (typeIdDef.valueShape == JsonToken.START_ARRAY) {
+        if ((typeIdDef != null)
+                && typeIdDef.valueShape == JsonToken.START_ARRAY) {
             _serializeAsArrayContents(value, g, provider);
         } else {
             String str = (_formatter == null) ? value.toString() : value.format(_formatter);

datetime/src/main/java/com/fasterxml/jackson/datatype/jsr310/ser/YearMonthSerializer.java

@@ -82,7 +82,8 @@ public void serializeWithType(YearMonth value, JsonGenerator g,
         WritableTypeId typeIdDef = typeSer.writeTypePrefix(g,
                 typeSer.typeId(value, serializationShape(provider)));
         // need to write out to avoid double-writing array markers
-        if (typeIdDef.valueShape == JsonToken.START_ARRAY) {
+        if ((typeIdDef != null)
+                && typeIdDef.valueShape == JsonToken.START_ARRAY) {
             _serializeAsArrayContents(value, g, provider);
         } else {
             g.writeString((_formatter == null) ? value.toString() : value.format(_formatter));

datetime/src/test/java/com/fasterxml/jackson/datatype/jsr310/misc/DeductionTypeSerialization296Test.java

@@ -1,9 +1,6 @@
 package com.fasterxml.jackson.datatype.jsr310.misc;
 
-import java.time.LocalDate;
-import java.time.LocalDateTime;
-import java.time.LocalTime;
-import java.time.Month;
+import java.time.*;
 
 import org.junit.Assert;
 import org.junit.Test;
@@ -52,4 +49,36 @@ public void testLocalTime() throws Exception
         Assert.assertEquals(a2q("{'value':'09:22:57'}"),
                 MAPPER.writeValueAsString(new Wrapper(time)));
     }
+
+    @Test
+    public void testMonthDate() throws Exception
+    {
+        MonthDay date = MonthDay.of(Month.JANUARY, 17);
+        Assert.assertEquals(a2q("{'value':'--01-17'}"),
+                MAPPER.writeValueAsString(new Wrapper(date)));
+    }
+
+    @Test
+    public void testOffsetTime() throws Exception
+    {
+        OffsetTime time = OffsetTime.of(15, 43, 0, 0, ZoneOffset.of("+0300"));
+        Assert.assertEquals(a2q("{'value':'15:43+03:00'}"),
+                MAPPER.writeValueAsString(new Wrapper(time)));
+    }
+
+    @Test
+    public void testYearMonth() throws Exception
+    {
+        YearMonth date = YearMonth.of(1986, Month.JANUARY);
+        Assert.assertEquals(a2q("{'value':'1986-01'}"),
+                MAPPER.writeValueAsString(new Wrapper(date)));
+    }
+
+    @Test
+    public void testZoneId() throws Exception
+    {
+        ZoneId zone = ZoneId.of("America/Denver");
+        Assert.assertEquals(a2q("{'value':'America/Denver'}"),
+                MAPPER.writeValueAsString(new Wrapper(zone)));
+    }
 }

release-notes/VERSION-2.x

@@ -8,6 +8,11 @@ Modules:
 === Releases ===
 ------------------------------------------------------------------------
 
+2.16.2 (not yet released)
+
+#296: NPE when serializing a `LocalDate` or `LocalDateTime` using `AsDeductionTypeSerializer`
+ (reported by @mike-reynolds-savient)
+
 2.16.1 (24-Dec-2023)
 
 #286: Breaking change in `InstantDeserializer API between 2.15 and 2.16