exposing method in PolymorphicReflectionCodec

axelspringer · Nov 7, 2017 · 0f5b66c · 0f5b66c
1 parent 85cd814
commit 0f5b66c
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Showing 4 changed files with 30 additions and 12 deletions.
diff --git a/README.md b/README.md
@@ -20,7 +20,7 @@ Note: There are plenty of code examples to be found in the tests.
 Attention: In order to scan packages you need to provide either [spring-core](https://github.com/spring-projects/spring-framework) library or [org.reflections.reflections](https://github.com/ronmamo/reflections) library in the class path.
 Alternatively you could register all your POJO classes one by one!
 
-Instantiate the POJOCodecProvider and add it to the CodecRegistry.
+Instantiate the [PojoCodecProvider](src/main/java/de/bild/codec/PojoCodecProvider.java) and add it to the CodecRegistry.
 Example: [PolymorphicReflectionCodecTest](src/test/java/de/bild/codec/PolymorphicReflectionCodecTest.java)
 
 One motivation to start this project was the missing feature of existing Pojo-codec solutions to easily model polymorphic structures and write/read those to/from the database (e.g.[https://github.com/mongodb/morphia/issues/22](https://github.com/mongodb/morphia/issues/22))

diff --git a/pom.xml b/pom.xml
@@ -6,7 +6,7 @@
 
     <groupId>de.bild.backend</groupId>
     <artifactId>polymorphia</artifactId>
-    <version>1.2.0</version>
+    <version>1.3.0</version>
 
     <name>${project.groupId}:${project.artifactId}</name>
 

diff --git a/src/main/java/de/bild/codec/PolymorphicReflectionCodec.java b/src/main/java/de/bild/codec/PolymorphicReflectionCodec.java
@@ -32,7 +32,7 @@ public PolymorphicReflectionCodec(Type type, Set<Type> validTypes, TypeCodecRegi
         boolean isAnyCodecCollectible = false;
 
         for (Type validType : validTypes) {
-            Class<?> clazz = AbstractTypeCodec.extractClass(validType);
+            Class<T> clazz = AbstractTypeCodec.extractClass(validType);
             if (!clazz.isInterface()) {
                 String discriminatorKey = getDiscriminatorKeyForClass(clazz);
                 boolean isFallBack = clazz.getDeclaredAnnotation(DiscriminatorFallback.class) != null;
@@ -162,13 +162,17 @@ protected T decodeWithType(BsonReader reader, DecoderContext decoderContext, Ref
 
     @Override
     public void encode(BsonWriter writer, T value, EncoderContext encoderContext) {
+        writer.writeStartDocument();
+        encodeFields(writer, value, encoderContext);
+        writer.writeEndDocument();
+    }
+
+    public void encodeFields(BsonWriter writer, T value, EncoderContext encoderContext) {
         ReflectionCodec<T> codecForValue = getCodecForClass(value.getClass());
         if (codecForValue != null) {
-            writer.writeStartDocument();
             writer.writeName(discriminatorKeys.get(codecForValue.getEncoderClass()));
             writer.writeString(mainDiscriminators.get(codecForValue.getEncoderClass()));
             encodeType(writer, value, encoderContext, codecForValue);
-            writer.writeEndDocument();
         } else {
             LOGGER.warn("The value to be encoded has the wrong type {}. This codec can only handle {}", value.getClass(), discriminatorToCodec);
         }
@@ -185,10 +189,11 @@ private ReflectionCodec getCodecForDiscriminator(String discriminator) {
 
     /**
      * Walks up class hierarchy until a registered codec (in the context of registered model classes) is found
+     *
      * @return a codec responsible for a valid class within the class hierarchy
      */
-    private ReflectionCodec<T> getCodecForClass(Class<?> clazz) {
-        if (Object.class.equals(clazz)) {
+    public ReflectionCodec<T> getCodecForClass(Class<?> clazz) {
+        if (clazz == null || Object.class.equals(clazz)) {
             return null;
         }
         ReflectionCodec<T> codec = classToCodec.get(clazz);

diff --git a/src/test/java/de/bild/codec/CodecResolverTest.java b/src/test/java/de/bild/codec/CodecResolverTest.java
@@ -3,6 +3,7 @@
 import com.mongodb.MongoClient;
 import com.mongodb.client.MongoCollection;
 import com.mongodb.client.model.Filters;
+import de.bild.codec.annotations.DiscriminatorKey;
 import de.bild.codec.annotations.Id;
 import org.apache.commons.lang3.reflect.TypeUtils;
 import org.bson.BsonReader;
@@ -54,7 +55,7 @@ public static CodecRegistry getCodecRegistry() {
                                     .register(CodecResolverTest.class)
                                     .registerCodecResolver((CodecResolver) (type, typeCodecRegistry) -> {
                                         if (TypeUtils.isAssignable(type, Base.class)) {
-                                            return new DocumentCodec(type, typeCodecRegistry);
+                                            return new DocumentCodec((Class<? extends Base>) type, typeCodecRegistry);
                                         }
                                         return null;
                                     })
@@ -70,7 +71,11 @@ public static CodecRegistry getCodecRegistry() {
     @Autowired
     private MongoClient mongoClient;
 
-    static class MetaData {
+    static class MetaBase {
+
+    }
+
+    static class MetaData extends MetaBase {
         @Id(collectible = true)
         ObjectId id;
         long version;
@@ -148,13 +153,21 @@ public int hashCode() {
 
 
     static class DocumentCodec<T extends Base> extends BasicReflectionCodec<T> {
-        private final ReflectionCodec<MetaData> documentMetaCodec;
+        final ReflectionCodec<MetaData> documentMetaCodec;
 
-        public DocumentCodec(Type type, TypeCodecRegistry typeCodecRegistry) {
+        public DocumentCodec(Class<T> type, TypeCodecRegistry typeCodecRegistry) {
             super(type, typeCodecRegistry);
-            this.documentMetaCodec = (ReflectionCodec<MetaData>) getMappedField("meta").getCodec();
+            MappedField mappedField = getMappedField("meta");
+            Codec metaCodec = mappedField.getCodec();
+            if (metaCodec instanceof PolymorphicReflectionCodec) {
+                PolymorphicReflectionCodec<MetaData> polymorphicMetaCodec = (PolymorphicReflectionCodec<MetaData>) metaCodec;
+                this.documentMetaCodec = polymorphicMetaCodec.getCodecForClass(mappedField.getField().getType());
+            } else {
+                this.documentMetaCodec = (ReflectionCodec<MetaData>) metaCodec;
+            }
         }
 
+
         @Override
         public T decodeFields(BsonReader reader, DecoderContext decoderContext, T instance) {
             MetaData documentMeta = instance.getMeta();