1 files changed, 54 insertions, 0 deletions
diff --git a/common/openecomp-logging-lib/openecomp-logging-api/src/main/java/org/openecomp/core/logging/api/BaseFactory.java b/common/openecomp-logging-lib/openecomp-logging-api/src/main/java/org/openecomp/core/logging/api/BaseFactory.java
new file mode 100644
index 0000000000..14943805cc
--- /dev/null
+++ b/common/openecomp-logging-lib/openecomp-logging-api/src/main/java/org/openecomp/core/logging/api/BaseFactory.java
@@ -0,0 +1,54 @@
+/*-
+ * ============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.logging.api;
+
+import java.util.Iterator;
+import java.util.ServiceLoader;
+
+/**
+ * Contains common functionality for factories used in the logging framework. <p>In order to use the
+ * factory, a particular (e.g. framework-specific) implementation of a service must be configured as
+ * described in <a href="http://docs.oracle.com/javase/8/docs/api/java/util/ServiceLoader.html">java.util.ServiceLoader</a>).</p>
+ *
+ * @see java.util.ServiceLoader
+ */
+public class BaseFactory {
+
+  protected static <T> T locateService(Class<T> clazz) throws Exception {
+
+    T service;
+    ServiceLoader<T> loader = ServiceLoader.load(clazz);
+    Iterator<T> iterator = loader.iterator();
+    if (iterator.hasNext()) {
+
+      service = iterator.next();
+      if (iterator.hasNext()) {
+        System.err.println(String.format("Warning! Configured more than one implementation of %s",
+            clazz.getName()));
+      }
+
+      return service;
+    }
+
+    throw new IllegalArgumentException(
+        (String.format("No implementations configured for %s", clazz.getName())));
+  }
+}