fix(nlc): add a deprecation message (#1185)

* fix(nlc): add a deprecation message on Natural Language Classifier logger

* fix(nlc): update deprecated annotation for Natural Language Classifier

Co-authored-by: Michael G Mosca <moscam@us.ibm.com>

Author: nan2iz

natural-language-classifier/src/main/java/com/ibm/watson/natural_language_classifier/v1/NaturalLanguageClassifier.java

@@ -52,6 +52,14 @@
  * @see <a href="https://cloud.ibm.com/docs/natural-language-classifier">Natural Language
  *     Classifier</a>
  */
+
+ /**
+ * @deprecated On 9 August 2021, IBM announced the deprecation of the Natural Language Classifier service.
+ * The service will no longer be available from 8 August 2022. As of 9 September 2021, you will not be able to create new instances.
+ * Existing instances will be supported until 8 August 2022. Any instance that still exists on that date will be deleted.
+ * (https://github.com/watson-developer-cloud/java-sdk/tree/master#natural-language-classifier-deprecation).
+ */
+@Deprecated
 public class NaturalLanguageClassifier extends BaseService {
 
   public static final String DEFAULT_SERVICE_NAME = "natural_language_classifier";
@@ -100,6 +108,12 @@ public NaturalLanguageClassifier(String serviceName, Authenticator authenticator
     super(serviceName, authenticator);
     setServiceUrl(DEFAULT_SERVICE_URL);
     this.configureService(serviceName);
+
+    System.err.println(
+      "On 9 August 2021, IBM announced the deprecation of the Natural Language Classifier service."
+        + "\nThe service will no longer be available from 8 August 2022. As of 9 September 2021, you will not be able to create new instances." 
+        + "\nExisting instances will be supported until 8 August 2022. Any instance that still exists on that date will be deleted."
+        + "\n(https://github.com/watson-developer-cloud/java-sdk/tree/master#natural-language-classifier-deprecation).");
   }
 
   /**