Inner classes couldn't extend marshallers because cannot be Serializable

src/main/java/net/openhft/chronicle/hash/serialization/impl/InstanceCreatingMarshaller.java

@@ -63,10 +63,11 @@ public abstract class InstanceCreatingMarshaller<T> implements Serializable {
                     tClass + " by default, delegates to \n" +
                     this.getClass().getName() + " which assumes the type has a public no-arg\n" +
                     "constructor. If this is not true, you should either extend the marshaller,\n" +
-                    "overriding createInstance() and copy() (if defined), or write and\n" +
-                    "configure your own marshaller for " + tClass + " type from scratch, and\n" +
-                    "configure for the Chronicle Map via keyMarshaller[s]() or\n" +
-                    "valueMarshaller[s]() methods", e);
+                    "overriding createInstance() and copy() (if defined), and the extending\n" +
+                    "class shouldn't be inner, because such classes couldn't be Serializable\n" +
+                    "that is a requirement for marshaller classes, or write and configure your\n" +
+                    "own marshaller for " + tClass + " type from scratch, and configure for the\n" +
+                    "Chronicle Map via keyMarshaller[s]() or valueMarshaller[s]() methods", e);
         }
     }
 }

src/test/java/net/openhft/chronicle/map/CHMUseCasesTest.java

@@ -2638,16 +2638,10 @@ public class CHMUseCasesTest {
 
     @Test
     public void testBytesMarshallable2() throws IOException {
-        BytesMarshallableReader<Data> dataReader = new BytesMarshallableReader<Data>(Data.class) {
-            @Override
-            protected Data createInstance() {
-                return new Data();
-            }
-        };
         ChronicleMapBuilder<Data, Data> builder = ChronicleMapBuilder
                 .of(Data.class, Data.class)
-                .keyReaderAndDataAccess(dataReader, new DataDataAccess())
-                .valueReaderAndDataAccess(dataReader, new DataDataAccess())
+                .keyReaderAndDataAccess(new DataReader(), new DataDataAccess())
+                .valueReaderAndDataAccess(new DataReader(), new DataDataAccess())
                 .actualChunkSize(64)
                 .entries(1000);
         try (ChronicleMap<Data, Data> map = newInstance(builder)) {
@@ -2680,6 +2674,17 @@ public class CHMUseCasesTest {
             return new DataDataAccess();
         }
     }
+
+    private static class DataReader extends BytesMarshallableReader<Data> {
+        public DataReader() {
+            super(Data.class);
+        }
+
+        @Override
+        protected Data createInstance() {
+            return new Data();
+        }
+    }
 }
 
 interface IData extends BytesMarshallable {

src/test/java/net/openhft/chronicle/map/ConstantSizeBySampleTest.java

@@ -89,13 +89,8 @@ public class ConstantSizeBySampleTest {
     public void testUnexpectedlyLongConstantExternalizableValues() throws IOException {
         try (  ChronicleMap<Long, ExternalizableData> map =
                 ChronicleMapBuilder.of(Long.class, ExternalizableData.class)
-                        .valueReaderAndDataAccess(new ExternalizableReader<ExternalizableData>(
-                                ExternalizableData.class) {
-                            @Override
-                            protected ExternalizableData createInstance() {
-                                return new ExternalizableData();
-                            }
-                        }, new ExternalizableDataDataAccess())
+                        .valueReaderAndDataAccess(new ExternalizableDataReader(),
+                                new ExternalizableDataDataAccess())
                         .constantValueSizeBySample(new ExternalizableData())
                         .entries(100)
                         .actualSegments(1)
@@ -134,7 +129,7 @@ public class ConstantSizeBySampleTest {
     }
 
     private static class ExternalizableDataDataAccess
-            extends ExternalizableDataAccess<ExternalizableData> {
+            extends ExternalizableDataAccess<ExternalizableData> implements Serializable {
         public ExternalizableDataDataAccess() {
             super(ExternalizableData.class);
         }
@@ -149,4 +144,15 @@ public class ConstantSizeBySampleTest {
             return new ExternalizableDataDataAccess();
         }
     }
+
+    private static class ExternalizableDataReader extends ExternalizableReader<ExternalizableData> {
+        public ExternalizableDataReader() {
+            super(ExternalizableData.class);
+        }
+
+        @Override
+        protected ExternalizableData createInstance() {
+            return new ExternalizableData();
+        }
+    }
 }