Merge pull request #7 from kaiso/feature/#4

[FEATURE#4] add the collection attribute when storing the reference i…

Author: kaiso

src/main/java/io/github/kaiso/relmongo/events/callback/PersistentPropertySavingCallback.java

@@ -23,7 +23,10 @@
 import io.github.kaiso.relmongo.annotation.JoinProperty;
 import io.github.kaiso.relmongo.annotation.OneToMany;
 import io.github.kaiso.relmongo.annotation.OneToOne;
+import io.github.kaiso.relmongo.util.ReflectionsUtil;
+import io.github.kaiso.relmongo.util.RelMongoConstants;
 
+import org.springframework.data.mongodb.core.mapping.Document;
 import org.springframework.util.ReflectionUtils;
 import org.springframework.util.ReflectionUtils.FieldCallback;
 
@@ -57,22 +60,27 @@ private void saveAssociation(Field field) {
         Object reference = null;
         try {
             reference = ((BasicDBObject) source).get(field.getName());
+            String collection = getCollectionName(field);
             if (reference instanceof BasicDBList) {
                 BasicDBList list = new BasicDBList();
-                list.addAll(((BasicDBList) reference).stream().map(this::keepOnlyIdentifier).collect(Collectors.toList()));
+                list.addAll(((BasicDBList) reference).stream().map(dbObject -> this.keepOnlyIdentifier(dbObject, collection)).collect(Collectors.toList()));
                 ((BasicDBObject) source).remove(field.getName());
                 ((BasicDBObject) source).put(name, list);
             } else if (reference instanceof BasicDBObject) {
                 ((BasicDBObject) source).remove(field.getName());
-                ((BasicDBObject) source).put(name, this.keepOnlyIdentifier(reference));
+                ((BasicDBObject) source).put(name, this.keepOnlyIdentifier(reference, collection));
             }
         } catch (Exception e) {
             throw new IllegalArgumentException("Property defined in @JoinProperty annotation is not present", e);
         }
     }
 
-    private BasicDBObject keepOnlyIdentifier(Object obj) {
-        return new BasicDBObject().append("_id", ((DBObject) obj).get("_id"));
+    private BasicDBObject keepOnlyIdentifier(Object obj, String collection) {
+        return new BasicDBObject().append("_id", ((DBObject) obj).get("_id")).append(RelMongoConstants.RELMONGOTARGET_PROPERTY_NAME, collection);
+    }
+
+    private String getCollectionName(Field field) {
+        return ReflectionsUtil.getGenericType(field).getAnnotation(Document.class).collection();
     }
 
 }

src/main/java/io/github/kaiso/relmongo/mongo/PersistentRelationResolver.java

@@ -24,6 +24,7 @@
 import io.github.kaiso.relmongo.lazy.LazyLoadingProxy;
 import io.github.kaiso.relmongo.lazy.RelMongoLazyLoader;
 import io.github.kaiso.relmongo.model.LoadableObjectsMetadata;
+import io.github.kaiso.relmongo.util.RelMongoConstants;
 
 import org.springframework.cglib.proxy.Enhancer;
 import org.springframework.cglib.proxy.Factory;
@@ -83,7 +84,21 @@ public static Object lazyLoader(Class<?> type, Object original, MongoOperations
     private static boolean hasToLoad(BasicDBList objects) {
         // the last contition verifies if the objects were already laoded by another
         // query
-        return !objects.isEmpty() && ((BasicDBObject) objects.get(0)).size() <= 1;
+        if (objects.isEmpty())
+            return false;
+        BasicDBObject basicDBObject = (BasicDBObject) objects.get(0);
+        return hasToLoad(basicDBObject);
+    }
+
+    /**
+     * checks if an object is already populated to be loaded anther time or not
+     * 
+     * @param basicDBObject
+     * @return
+     */
+    private static boolean hasToLoad(BasicDBObject basicDBObject) {
+        int propscount = basicDBObject.get(RelMongoConstants.RELMONGOTARGET_PROPERTY_NAME) == null ? 1 : 2;
+        return basicDBObject.size() <= propscount;
     }
 
     public static Object mapIdentifier(Object object) {

src/main/java/io/github/kaiso/relmongo/util/RelMongoConstants.java

@@ -0,0 +1,11 @@
+package io.github.kaiso.relmongo.util;
+
+public final class RelMongoConstants {
+
+    private RelMongoConstants() {
+        super();
+    }
+
+    public static final String RELMONGOTARGET_PROPERTY_NAME = "_relmongo_target";
+
+}

src/test/java/io/github/kaiso/relmongo/tests/PersonRepositoryTest.java

@@ -15,6 +15,7 @@
 import io.github.kaiso.relmongo.data.repository.PassportRepository;
 import io.github.kaiso.relmongo.data.repository.PersonRepository;
 import io.github.kaiso.relmongo.tests.common.AbstractBaseTest;
+import io.github.kaiso.relmongo.util.RelMongoConstants;
 
 import org.junit.jupiter.api.BeforeEach;
 import org.junit.jupiter.api.Test;
@@ -104,6 +105,7 @@ public void shouldPersistOnlyReferencedPropertyOnOneToOneRelation() {
         System.out.println("relational id" + passport.getId());
         BasicDBObject obj = new BasicDBObject();
         obj.put("_id", passport.getId());
+        obj.put(RelMongoConstants.RELMONGOTARGET_PROPERTY_NAME  ,"passports");
         assertEquals(personNoRelational.get("passportref"), obj);
     }