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diff --git a/openecomp-be/lib/openecomp-core-lib/openecomp-facade-lib/openecomp-facade-api/src/main/java/org/openecomp/core/factory/api/AbstractFactory.java b/openecomp-be/lib/openecomp-core-lib/openecomp-facade-lib/openecomp-facade-api/src/main/java/org/openecomp/core/factory/api/AbstractFactory.java
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+++ b/openecomp-be/lib/openecomp-core-lib/openecomp-facade-lib/openecomp-facade-api/src/main/java/org/openecomp/core/factory/api/AbstractFactory.java
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+/*-
+ * ============LICENSE_START=======================================================
+ * SDC
+ * ================================================================================
+ * Copyright (C) 2017 AT&T Intellectual Property. All rights reserved.
+ * ================================================================================
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ * 
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ * ============LICENSE_END=========================================================
+ */
+
+package org.openecomp.core.factory.api;
+
+import org.openecomp.core.factory.impl.AbstractFactoryBase;
+
+/**
+ * This class provides generic implementation of an abstract factory. Components exposed as Java
+ * interfaces should have their own concrete factories derived from the given class. This assures
+ * code alignment and consistency across all Service Management components.
+ * The class actually
+ * uses singleton pattern to instantiate and reuse just one instance of a factory. Therefore, each
+ * factory implementation has to be <i>thread-safe</i>.
+ * In a general case, the hierarchy of
+ * factory objects for an Java interface <tt>IUknown</tt> may look as follows:
+ * <pre>
+ *                     AbstractFactory&lt;IUnknown&gt;
+ *                                ^
+ *                                |
+ *   Application code ----> ConcreteFactory
+ *                                ^
+ *                                |
+ *                      +---------+---------+
+ *                      |                   |
+ *             BaselineFactoryImpl   CustomFactoryImpl
+ * </pre>
+ * Where the classes responsibility is: <ul> <li>Abstract factory - common logic to retrieve the
+ * implementation class name from a central repository.</li> <li>Concrete factory - abstract class
+ * that only exposes to application layer the type specific API such as: <ul> <li><tt>public static
+ * ConcreteFactory getInstance()</tt></li> </ul> <li>Baseline factory - out of the box
+ * implementation of concrete factory (that can be replaced by a custom one depending on customer
+ * needs) which actually implements method: <ul> <li><tt>public IUnknown createInterface()</tt></li>
+ * </ul> </ul> The normal concrete factory class may look like:
+ * <pre>
+ * public abstract class ConcreteFactory extends AbstractFactory&lt;IUnknown&gt; {
+ *   static {
+ *     registerFactory(ConcreteFactory.class, BaselineFactoryImpl.class);
+ *   }
+ * public static ConcreteFactory getInstance() {
+ * return AbstractFactory.&lt;IUnknown, ConcreteFactory.class&gt;getInstance(ConcreteFactory.class);
+ *   }
+ * }
+ * </pre>
+ *
+ * @param <I> Java interface type created by the factory.
+ */
+public abstract class AbstractFactory<I> extends AbstractFactoryBase {
+
+
+  /**
+   * Returns the interface implementor instance.
+   * <b>Note</b>: It's up to the concrete factory to decide on the actual
+   * implementation of the returned interface. Therefore, the call can get the
+   * same instance per each call in case of singleton implementation or new
+   * instance otherwise. However, the API consumer may not assume anything
+   * regarding the underlying logic and has always go through the factory to
+   * obtain the reference.
+   *
+   * @return Implementor of the exposed Java interface.
+   */
+  public abstract I createInterface();
+
+} // End of class