1 files changed, 93 insertions, 0 deletions
diff --git a/openecomp-be/lib/openecomp-sdc-logging-lib/openecomp-sdc-logging-api/src/main/java/org/openecomp/sdc/logging/api/ServiceBinder.java b/openecomp-be/lib/openecomp-sdc-logging-lib/openecomp-sdc-logging-api/src/main/java/org/openecomp/sdc/logging/api/ServiceBinder.java
new file mode 100644
index 0000000000..b16f3944e9
--- /dev/null
+++ b/openecomp-be/lib/openecomp-sdc-logging-lib/openecomp-sdc-logging-api/src/main/java/org/openecomp/sdc/logging/api/ServiceBinder.java
@@ -0,0 +1,93 @@
+/*
+ * Copyright © 2016-2017 European Support Limited
+ *
+ * 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.
+ */
+
+package org.openecomp.sdc.logging.api;
+
+import org.openecomp.sdc.logging.provider.LoggerCreationService;
+import org.openecomp.sdc.logging.provider.LoggingContextService;
+import org.openecomp.sdc.logging.provider.LoggingServiceProvider;
+
+import java.util.Iterator;
+import java.util.Optional;
+import java.util.ServiceLoader;
+
+/**
+ * <p>Binds to a concrete implementation of logging services.</p>
+ *
+ * <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>
+ *
+ * @author evitaliy
+ * @since 13/09/2016.
+ *
+ * @see ServiceLoader
+ */
+
+// No advanced logging can be used here because we don't know
+// which underlying implementation will be used
+@SuppressWarnings({"UseOfSystemOutOrSystemErr", "squid:S106"})
+class ServiceBinder {
+
+    private static final LoggingServiceProvider PROVIDER = lookupProvider();
+
+    private ServiceBinder () {
+        // prevent instantiation
+    }
+
+    private static LoggingServiceProvider lookupProvider() {
+
+        ServiceLoader<LoggingServiceProvider> loader = ServiceLoader.load(LoggingServiceProvider.class);
+        Iterator<LoggingServiceProvider> iterator = loader.iterator();
+
+        if (!iterator.hasNext()) {
+            System.err.printf("[ERROR] No provider configured for logging services %s. " +
+                            "Default implementation will be used.\n",
+                    LoggingServiceProvider.class.getName());
+            return null;
+        }
+
+        try {
+
+            LoggingServiceProvider provider = iterator.next();
+            if (!iterator.hasNext()) {
+                return provider;
+            }
+
+            Logger logger = provider.getLogger(ServiceBinder.class);
+            if (logger.isWarnEnabled()) {
+                logger.warn("More than one provider for logging services {} found",
+                        LoggingServiceProvider.class.getName());
+            }
+
+            return provider;
+
+        } catch (Exception e) {
+            // don't fail if the provider cannot be instantiated
+            e.printStackTrace(System.err);
+            return null;
+        }
+    }
+
+    static Optional<LoggingContextService> getContextServiceBinding() {
+        return Optional.ofNullable(PROVIDER);
+    }
+
+    static Optional<LoggerCreationService> getCreationServiceBinding() {
+        return Optional.ofNullable(PROVIDER);
+    }
+}
+