1 files changed, 56 insertions, 0 deletions
diff --git a/openecomp-be/lib/openecomp-sdc-logging-lib/openecomp-sdc-logging-core/src/main/java/org/openecomp/sdc/logging/slf4j/Context.java b/openecomp-be/lib/openecomp-sdc-logging-lib/openecomp-sdc-logging-core/src/main/java/org/openecomp/sdc/logging/slf4j/Context.java
new file mode 100644
index 0000000000..25784fefcd
--- /dev/null
+++ b/openecomp-be/lib/openecomp-sdc-logging-lib/openecomp-sdc-logging-core/src/main/java/org/openecomp/sdc/logging/slf4j/Context.java
@@ -0,0 +1,56 @@
+/*
+ * 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.slf4j;
+
+import java.util.Map;
+
+/**
+ * Does not store a state other than initial context values. Objects of this class may be reused by multiple threads,
+ * therefore they must be stateless to prevent inadvertent exchange of context values between threads.
+ *
+ * @author evitaliy
+ * @since 08 Jan 2018
+ */
+final class Context {
+
+    private final Map<ContextField, String> originalCtx;
+
+    Context() {
+        this.originalCtx = MDCDelegate.copy();
+    }
+
+    /**
+     * Pushes the initial context onto current thread, and returns the existing context. The result cannot be stored as
+     * local state (see the class comments), and must be kept in a local variable to work properly.
+     *
+     * @return previous context values
+     */
+    final Map<ContextField, String> replace() {
+        Map<ContextField, String> old = MDCDelegate.copy();
+        MDCDelegate.replace(this.originalCtx);
+        return old;
+    }
+
+    /**
+     * Pushes an old context onto current thread.
+     *
+     * @param old copy of the old context returned by {@link #replace()}
+     */
+    final void revert(Map<ContextField, String> old) {
+        MDCDelegate.replace(old);
+    }
+}