Update release notes wrt #360; test clean up

release-notes/CREDITS-2.x

@@ -115,6 +115,12 @@ Jochen Schalanda (joschi@github)
 * Reported #318: XMLMapper fails to deserialize null (POJO reference) from blank tag
  (2.12.0)
 
+Migwel@github
+
+* Contributed #360: Add a feature to support writing `xsi:nil` attribute for
+  `null` values
+ (2.12.0)
+
 Ingo Wiarda (dewarim@github)
 
 * Reported #374: Deserialization fails with `XmlMapper` and

release-notes/VERSION-2.x

@@ -35,6 +35,8 @@ Project: jackson-dataformat-xml
  (reported by Jochen S)
 #319: Empty root tag into `List` deserialization bug
  (reported by Seatec13@github)
+#360: Add a feature to support writing `xsi:nil` attribute for `null` values
+ (contributed by Migwel@github)
 #374: Deserialization fails with `XmlMapper` and `DeserializationFeature.UNWRAP_ROOT_VALUE`
  (reported by Ingo W)
 #377: `ToXmlGenerator` ignores `Base64Variant` while serializing `byte[]`

src/test/java/com/fasterxml/jackson/dataformat/xml/ser/CustomSerializerTest.java

@@ -0,0 +1,36 @@
+package com.fasterxml.jackson.dataformat.xml.ser;
+
+import java.io.IOException;
+
+import com.fasterxml.jackson.core.JsonGenerator;
+import com.fasterxml.jackson.databind.SerializerProvider;
+import com.fasterxml.jackson.databind.module.SimpleModule;
+import com.fasterxml.jackson.databind.ser.std.StdScalarSerializer;
+import com.fasterxml.jackson.dataformat.xml.XmlMapper;
+import com.fasterxml.jackson.dataformat.xml.XmlTestBase;
+
+public class CustomSerializerTest extends XmlTestBase
+{
+    @SuppressWarnings("serial")
+    static class CustomSerializer extends StdScalarSerializer<String>
+    {
+        public CustomSerializer() { super(String.class); }
+
+        @Override
+        public void serialize(String value, JsonGenerator jgen,
+                SerializerProvider provider) throws IOException {
+            jgen.writeString("custom:"+value);
+        }
+    }
+
+    // for [dataformat-xml#41]
+    public void testCustomSerializer() throws Exception
+    {
+        SimpleModule module = new SimpleModule();
+        module.addSerializer(String.class, new CustomSerializer());
+        final XmlMapper mapper = XmlMapper.builder()
+                .addModule(module)
+                .build();
+        assertEquals("<String>custom:foo</String>", mapper.writeValueAsString("foo"));
+    }
+}

src/test/java/com/fasterxml/jackson/dataformat/xml/ser/NullSerializationTest.java

@@ -0,0 +1,33 @@
+package com.fasterxml.jackson.dataformat.xml.ser;
+
+import java.io.IOException;
+
+import com.fasterxml.jackson.dataformat.xml.XmlMapper;
+import com.fasterxml.jackson.dataformat.xml.XmlTestBase;
+
+public class NullSerializationTest extends XmlTestBase
+{
+    static class WrapperBean<T>
+    {
+        public T value;
+
+        public WrapperBean() { }
+        public WrapperBean(T v) { value = v; }
+    }
+
+    // [dataformat-xml#360]
+    public void testNil() throws IOException
+    {
+        final XmlMapper mapper = XmlMapper.builder()
+                .configure(ToXmlGenerator.Feature.WRITE_NULLS_AS_XSI_NIL, true)
+                .build();
+
+        // First, map in a general wrapper
+        assertEquals("<WrapperBean><value xmlns:xsi=\"http://www.w3.org/2001/XMLSchema-instance\" xsi:nil=\"true\"/></WrapperBean>",
+                mapper.writeValueAsString(new WrapperBean<>(null)));
+
+        // and then as root -- not sure what it should exactly look like but...
+        String xml = mapper.writeValueAsString(null);
+        assertEquals("<null xmlns:xsi=\"http://www.w3.org/2001/XMLSchema-instance\" xsi:nil=\"true\"/>", xml);
+    }
+}

src/test/java/com/fasterxml/jackson/dataformat/xml/ser/TestSerialization.java

@@ -3,10 +3,6 @@
 import java.io.*;
 import java.util.*;
 
-import com.fasterxml.jackson.core.JsonGenerator;
-import com.fasterxml.jackson.databind.SerializerProvider;
-import com.fasterxml.jackson.databind.ser.std.StdScalarSerializer;
-import com.fasterxml.jackson.dataformat.xml.JacksonXmlModule;
 import com.fasterxml.jackson.dataformat.xml.XmlMapper;
 import com.fasterxml.jackson.dataformat.xml.XmlTestBase;
 import com.fasterxml.jackson.dataformat.xml.annotation.JacksonXmlCData;
@@ -68,17 +64,6 @@ static class CDataStringArrayBean
         public String[] value = {"<some<data\"", "abc"};
     }
 
-    static class CustomSerializer extends StdScalarSerializer<String>
-    {
-        public CustomSerializer() { super(String.class); }
-
-        @Override
-        public void serialize(String value, JsonGenerator jgen,
-                SerializerProvider provider) throws IOException {
-            jgen.writeString("custom:"+value);
-        }
-    }
-
     static class CustomMap extends LinkedHashMap<String, Integer> { }
 
     /*
@@ -87,7 +72,7 @@ static class CustomMap extends LinkedHashMap<String, Integer> { }
     /**********************************************************
      */
 
-    protected XmlMapper _xmlMapper = new XmlMapper();
+    private final XmlMapper _xmlMapper = new XmlMapper();
 
     public void testSimpleAttribute() throws IOException
     {
@@ -111,17 +96,6 @@ public void testSimpleAttrAndElem() throws IOException
         assertEquals("<AttrAndElem id=\"42\"><elem>whatever</elem></AttrAndElem>", xml);
     }
 
-    public void testNil() throws IOException
-    {
-        XmlMapper mapper = new XmlMapper();
-        mapper.configure(ToXmlGenerator.Feature.WRITE_NULLS_AS_XSI_NIL, true);
-        WrapperBean<String> bean = new WrapperBean<>(null);
-        // First, map in a general wrapper
-        String xml = mapper.writeValueAsString(bean);
-        assertEquals("<WrapperBean><value xmlns:xsi=\"http://www.w3.org/2001/XMLSchema-instance\" xsi:nil=\"true\"/></WrapperBean>", xml);
-    }
-
-    @SuppressWarnings("boxing")
     public void testMap() throws IOException
     {
         // First, map in a general wrapper
@@ -176,15 +150,6 @@ public void testCDataStringArray() throws IOException
         xml = removeSjsxpNamespace(xml);
         assertEquals("<CDataStringArrayBean><value><value><![CDATA[<some<data\"]]></value><value><![CDATA[abc]]></value></value></CDataStringArrayBean>", xml);
     }
-
-    // for [dataformat-xml#41]
-    public void testCustomSerializer() throws Exception
-    {
-        JacksonXmlModule module = new JacksonXmlModule();
-        module.addSerializer(String.class, new CustomSerializer());
-        XmlMapper xml = new XmlMapper(module);
-        assertEquals("<String>custom:foo</String>", xml.writeValueAsString("foo"));
-    }
 
     // manual 'test' to see "what would JAXB do?"
     /*