#250 extract collection callback, improve implementation

Author: aburmeis

src/main/java/com/arangodb/springframework/core/template/ArangoTemplate.java

@@ -45,7 +45,6 @@
 import com.arangodb.springframework.core.mapping.event.ArangoMappingEvent;
 import com.arangodb.springframework.core.mapping.event.BeforeDeleteEvent;
 import com.arangodb.springframework.core.mapping.event.BeforeSaveEvent;
-import com.arangodb.springframework.core.template.DefaultUserOperation.CollectionCallback;
 import com.arangodb.springframework.core.util.ArangoExceptionTranslator;
 import com.arangodb.springframework.core.util.MetadataUtils;
 import com.arangodb.util.MapBuilder;
@@ -761,8 +760,12 @@ public CollectionOperations collection(final Class<?> entityClass) throws DataAc
 	}
 
 	@Override
-	public CollectionOperations collection(String name) {
-		return ArangoOperations.super.collection(name);
+	public CollectionOperations collection(String name) throws DataAccessException {
+		ArangoPersistentEntity<?> persistentEntity = converter.getMappingContext().getPersistentEntities().stream()
+				.filter(e -> name.equals(e.getCollection()))
+				.findAny()
+				.orElse(null);
+		return collection(_collection(name, persistentEntity, persistentEntity == null ? new CollectionCreateOptions() : persistentEntity.getCollectionOptions(), false));
 	}
 
 	@Override

src/main/java/com/arangodb/springframework/core/template/CollectionCallback.java

@@ -0,0 +1,41 @@
+package com.arangodb.springframework.core.template;
+
+import com.arangodb.springframework.core.ArangoOperations;
+import com.arangodb.springframework.core.CollectionOperations;
+import org.springframework.dao.DataAccessException;
+
+/**
+ * Internal interface to handle collection operations.
+ * Typically implemented by same class as {@link com.arangodb.springframework.core.ArangoOperations}.
+ */
+public interface CollectionCallback {
+
+    /**
+     * @see com.arangodb.springframework.core.ArangoOperations#collection(Class)
+     */
+    CollectionOperations collection(Class<?> type) throws DataAccessException;
+
+    /**
+     * @see com.arangodb.springframework.core.ArangoOperations#collection(String)
+     */
+    CollectionOperations collection(String name) throws DataAccessException;
+
+
+    static CollectionCallback fromOperations(ArangoOperations operations) {
+        if (operations instanceof CollectionCallback) {
+            return (CollectionCallback) operations;
+        }
+        return new CollectionCallback() {
+            @Override
+            public CollectionOperations collection(Class<?> type) {
+                return operations.collection(type);
+            }
+
+            @Override
+            public CollectionOperations collection(String name) {
+                return operations.collection(name);
+            }
+        };
+    }
+
+}

src/main/java/com/arangodb/springframework/core/template/DefaultUserOperation.java

@@ -29,7 +29,6 @@
 import com.arangodb.entity.UserEntity;
 import com.arangodb.model.UserCreateOptions;
 import com.arangodb.model.UserUpdateOptions;
-import com.arangodb.springframework.core.CollectionOperations;
 import com.arangodb.springframework.core.UserOperations;
 
 /**
@@ -38,12 +37,6 @@
  */
 public class DefaultUserOperation implements UserOperations {
 
-	public interface CollectionCallback {
-		CollectionOperations collection(Class<?> type);
-
-		CollectionOperations collection(String name);
-	}
-
 	private final ArangoDatabase db;
 	private final String username;
 	private final PersistenceExceptionTranslator exceptionTranslator;