Extract required(...) method

Change-Id: I9a2a02aabd6b90c601f3bcd2cdd708e9af70d819
Issue-ID: DMAAP-1107
Signed-off-by: piotr.karas <piotr.karas@nokia.com>

14 files changed, 290 insertions, 197 deletions

diff --git a/src/main/java/org/onap/dmaap/dbcapi/model/ApiError.java b/src/main/java/org/onap/dmaap/dbcapi/model/ApiError.java
index 2e05740..c67e55b 100644
--- a/src/main/java/org/onap/dmaap/dbcapi/model/ApiError.java
+++ b/src/main/java/org/onap/dmaap/dbcapi/model/ApiError.java
@@ -21,10 +21,11 @@
 package org.onap.dmaap.dbcapi.model;
 
 import javax.xml.bind.annotation.XmlRootElement;
+import java.io.Serializable;
 import java.util.Objects;
 
 @XmlRootElement
-public class ApiError {
+public class ApiError implements Serializable {
 	private int code;
 	private String message;
 	private String fields;
diff --git a/src/main/java/org/onap/dmaap/dbcapi/resources/DR_NodeResource.java b/src/main/java/org/onap/dmaap/dbcapi/resources/DR_NodeResource.java
index 029222e..49dc69a 100644
--- a/src/main/java/org/onap/dmaap/dbcapi/resources/DR_NodeResource.java
+++ b/src/main/java/org/onap/dmaap/dbcapi/resources/DR_NodeResource.java
@@ -57,6 +57,7 @@ public class DR_NodeResource extends BaseLoggingClass {
 
 	private DR_NodeService dr_nodeService = new DR_NodeService();
 	private ResponseBuilder responseBuilder = new ResponseBuilder();
+	private RequiredChecker checker = new RequiredChecker();
 	
 	@GET
 	@ApiOperation( value = "return DR_Node details", 
@@ -88,8 +89,8 @@ public class DR_NodeResource extends BaseLoggingClass {
 		ApiService resp = new ApiService();
 
 		try {
-			resp.required( "dcaeLocation", node.getDcaeLocationName(), "");
-			resp.required( "fqdn", node.getFqdn(), "");
+			checker.required( "dcaeLocation", node.getDcaeLocationName());
+			checker.required( "fqdn", node.getFqdn());
 		} catch ( RequiredFieldException rfe ) {
 			return responseBuilder.error(new ApiError(BAD_REQUEST.getStatusCode(),
 					"missing required field", "dcaeLocation, fqdn"));
@@ -117,10 +118,10 @@ public class DR_NodeResource extends BaseLoggingClass {
 		ApiService resp = new ApiService();
 
 		try {
-			resp.required( "dcaeLocation", name, "");
-			resp.required( "fqdn", node.getFqdn(), "");
+			checker.required( "dcaeLocation", name);
+			checker.required( "fqdn", node.getFqdn());
 		} catch ( RequiredFieldException rfe ) {
-			return responseBuilder.error(resp.getErr());
+			return responseBuilder.error(rfe.getApiError());
 		}
 		node.setFqdn(name);
 		DR_Node nNode = dr_nodeService.updateDr_Node(node, resp.getErr());
@@ -146,10 +147,10 @@ public class DR_NodeResource extends BaseLoggingClass {
 		ApiService resp = new ApiService();
 
 		try {
-			resp.required( "fqdn", name, "");
+			checker.required( "fqdn", name);
 		} catch ( RequiredFieldException rfe ) {
-			logger.debug( resp.toString() );
-			return responseBuilder.error(resp.getErr());
+			logger.debug( rfe.getApiError().toString() );
+			return responseBuilder.error(rfe.getApiError());
 		}
 		dr_nodeService.removeDr_Node(name, resp.getErr());
 		if ( resp.getErr().is2xx() ) {
diff --git a/src/main/java/org/onap/dmaap/dbcapi/resources/DR_PubResource.java b/src/main/java/org/onap/dmaap/dbcapi/resources/DR_PubResource.java
index 9c2ae21..1054b03 100644
--- a/src/main/java/org/onap/dmaap/dbcapi/resources/DR_PubResource.java
+++ b/src/main/java/org/onap/dmaap/dbcapi/resources/DR_PubResource.java
@@ -60,6 +60,7 @@ public class DR_PubResource extends BaseLoggingClass {
 
 	private DR_PubService dr_pubService = new DR_PubService();
 	private ResponseBuilder responseBuilder = new ResponseBuilder();
+	private RequiredChecker checker = new RequiredChecker();
 	
 	@GET
 	@ApiOperation( value = "return DR_Pub details", 
@@ -96,13 +97,13 @@ public class DR_PubResource extends BaseLoggingClass {
 		logger.info( "Entry: POST /dr_pubs");
 
 		try {
-			resp.required( "feedId", pub.getFeedId(), "");
+			checker.required( "feedId", pub.getFeedId());
 		} catch ( RequiredFieldException rfe ) {
 			try {
-				resp.required( "feedName", pub.getFeedName(), "");
+				checker.required( "feedName", pub.getFeedName());
 			}catch ( RequiredFieldException rfe2 ) {
-				logger.debug( resp.toString() );
-				return responseBuilder.error(resp.getErr());
+				logger.debug( rfe2.getApiError().toString() );
+				return responseBuilder.error(rfe2.getApiError());
 			}
 			// if we found a FeedName instead of a FeedId then try to look it up.
 			List<Feed> nfeeds =  feeds.getAllFeeds( pub.getFeedName(), pub.getFeedVersion(), "equals");
@@ -113,10 +114,10 @@ public class DR_PubResource extends BaseLoggingClass {
 			fnew = nfeeds.get(0);
 		}
 		try {
-			resp.required( "dcaeLocationName", pub.getDcaeLocationName(), "");
+			checker.required( "dcaeLocationName", pub.getDcaeLocationName());
 		} catch ( RequiredFieldException rfe ) {
-			logger.debug( resp.getErr().toString() );
-			return responseBuilder.error(resp.getErr());
+			logger.debug( rfe.getApiError().toString() );
+			return responseBuilder.error(rfe.getApiError());
 		}
 
 
@@ -189,9 +190,9 @@ public class DR_PubResource extends BaseLoggingClass {
 		ApiService resp = new ApiService();
 
 		try {
-			resp.required( "pubId", id, "");
+			checker.required( "pubId", id);
 		} catch ( RequiredFieldException rfe ) {
-			return responseBuilder.error(resp.getErr());
+			return responseBuilder.error(rfe.getApiError());
 		}
 
 		DR_Pub pub =  dr_pubService.getDr_Pub( id, resp.getErr() );
@@ -245,9 +246,9 @@ public class DR_PubResource extends BaseLoggingClass {
 		ApiService resp = new ApiService();
 
 		try {
-			resp.required( "feedId", id, "");
+			checker.required( "feedId", id);
 		} catch ( RequiredFieldException rfe ) {
-			return responseBuilder.error(resp.getErr());
+			return responseBuilder.error(rfe.getApiError());
 		}
 
 		DR_Pub pub =  dr_pubService.getDr_Pub( id, resp.getErr() );
diff --git a/src/main/java/org/onap/dmaap/dbcapi/resources/DR_SubResource.java b/src/main/java/org/onap/dmaap/dbcapi/resources/DR_SubResource.java
index 01ac059..b74d5a1 100644
--- a/src/main/java/org/onap/dmaap/dbcapi/resources/DR_SubResource.java
+++ b/src/main/java/org/onap/dmaap/dbcapi/resources/DR_SubResource.java
@@ -62,6 +62,7 @@ import static javax.ws.rs.core.Response.Status.CREATED;
 public class DR_SubResource extends BaseLoggingClass {
 
 	private ResponseBuilder responseBuilder = new ResponseBuilder();
+	private RequiredChecker checker = new RequiredChecker();
 		
 	@GET
 	@ApiOperation( value = "return DR_Sub details", 
@@ -96,13 +97,13 @@ public class DR_SubResource extends BaseLoggingClass {
 		FeedService feeds = new FeedService();
 		Feed fnew = null;
 		try {
-			resp.required( "feedId", sub.getFeedId(), "");
+			checker.required( "feedId", sub.getFeedId());
 		} catch ( RequiredFieldException rfe ) {
 			try {
-				resp.required( "feedName", sub.getFeedName(), "");
+				checker.required( "feedName", sub.getFeedName());
 			}catch ( RequiredFieldException rfe2 ) {
-				logger.debug( resp.toString() );
-				return responseBuilder.error(resp.getErr());
+				logger.debug( rfe2.getApiError().toString() );
+				return responseBuilder.error(rfe2.getApiError());
 			}
 			// if we found a FeedName instead of a FeedId then try to look it up.
 			List<Feed> nfeeds =  feeds.getAllFeeds( sub.getFeedName(), sub.getFeedVersion(), "equals");
@@ -114,10 +115,10 @@ public class DR_SubResource extends BaseLoggingClass {
 		}
 			
 		try {
-			resp.required( "dcaeLocationName", sub.getDcaeLocationName(), "");
+			checker.required( "dcaeLocationName", sub.getDcaeLocationName());
 		} catch ( RequiredFieldException rfe ) {
-			logger.debug( resp.toString() );
-			return responseBuilder.error(resp.getErr());
+			logger.debug( rfe.getApiError().toString() );
+			return responseBuilder.error(rfe.getApiError());
 		}
 		// we may have fnew already if located by FeedName
 		if ( fnew == null ) {
@@ -161,13 +162,13 @@ public class DR_SubResource extends BaseLoggingClass {
 		ApiService resp = new ApiService();
 
 		try {
-			resp.required( "subId", name, "");
-			resp.required( "feedId", sub.getFeedId(), "");
-			resp.required( "dcaeLocationName", sub.getDcaeLocationName(), "");
+			checker.required( "subId", name);
+			checker.required( "feedId", sub.getFeedId());
+			checker.required( "dcaeLocationName", sub.getDcaeLocationName());
 	
 		} catch ( RequiredFieldException rfe ) {
-			logger.debug( resp.toString() );
-			return responseBuilder.error(resp.getErr());
+			logger.debug( rfe.getApiError().toString() );
+			return responseBuilder.error(rfe.getApiError());
 		}
 		FeedService feeds = new FeedService();
 		Feed fnew = feeds.getFeed( sub.getFeedId(), resp.getErr() );
@@ -201,10 +202,10 @@ public class DR_SubResource extends BaseLoggingClass {
 		ApiService resp = new ApiService();
 
 		try {
-			resp.required( "subId", id, "");
+			checker.required( "subId", id);
 		} catch ( RequiredFieldException rfe ) {
-			logger.debug( resp.toString() );
-			return responseBuilder.error(resp.getErr());
+			logger.debug( rfe.getApiError().toString() );
+			return responseBuilder.error(rfe.getApiError());
 		}
 		DR_SubService dr_subService = new DR_SubService();
 		dr_subService.removeDr_Sub(id, resp.getErr() );
@@ -229,10 +230,10 @@ public class DR_SubResource extends BaseLoggingClass {
 		ApiService resp = new ApiService();
 
 		try {
-			resp.required( "subId", id, "");
+			checker.required( "subId", id);
 		} catch ( RequiredFieldException rfe ) {
-			logger.debug( resp.toString() );
-			return responseBuilder.error(resp.getErr());
+			logger.debug( rfe.getApiError().toString() );
+			return responseBuilder.error(rfe.getApiError());
 		}
 		DR_SubService dr_subService = new DR_SubService();
 		DR_Sub sub =  dr_subService.getDr_Sub( id, resp.getErr() );
diff --git a/src/main/java/org/onap/dmaap/dbcapi/resources/DmaapResource.java b/src/main/java/org/onap/dmaap/dbcapi/resources/DmaapResource.java
index d7fb507..955cab7 100644
--- a/src/main/java/org/onap/dmaap/dbcapi/resources/DmaapResource.java
+++ b/src/main/java/org/onap/dmaap/dbcapi/resources/DmaapResource.java
@@ -7,9 +7,9 @@
  * 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.
@@ -24,11 +24,14 @@
 package org.onap.dmaap.dbcapi.resources;
 
 
-
 import io.swagger.annotations.Api;
 import io.swagger.annotations.ApiOperation;
 import io.swagger.annotations.ApiResponse;
 import io.swagger.annotations.ApiResponses;
+import org.onap.dmaap.dbcapi.logging.BaseLoggingClass;
+import org.onap.dmaap.dbcapi.model.ApiError;
+import org.onap.dmaap.dbcapi.model.Dmaap;
+import org.onap.dmaap.dbcapi.service.DmaapService;
 
 import javax.ws.rs.Consumes;
 import javax.ws.rs.GET;
@@ -41,13 +44,6 @@ import javax.ws.rs.core.MediaType;
 import javax.ws.rs.core.Response;
 import javax.ws.rs.core.UriInfo;
 
-import org.onap.dmaap.dbcapi.logging.BaseLoggingClass;
-import org.onap.dmaap.dbcapi.model.ApiError;
-import org.onap.dmaap.dbcapi.model.Dmaap;
-import org.onap.dmaap.dbcapi.service.ApiService;
-import org.onap.dmaap.dbcapi.service.DmaapService;
-
-
 
 @Path("/dmaap")
 @Api( value= "dmaap", description = "Endpoint for this instance of DMaaP object containing values for this OpenDCAE deployment" )
@@ -59,7 +55,8 @@ public class DmaapResource extends BaseLoggingClass {
 
 	private DmaapService dmaapService = new DmaapService();
 	private ResponseBuilder responseBuilder = new ResponseBuilder();
-	
+	private RequiredChecker checker = new RequiredChecker();
+
 	@GET
 	@ApiOperation( value = "return dmaap details", notes = "returns the `dmaap` object, which contains system wide configuration settings", response = Dmaap.class)
     @ApiResponses( value = {
@@ -71,7 +68,7 @@ public class DmaapResource extends BaseLoggingClass {
 		Dmaap d =  dmaapService.getDmaap();
 		return responseBuilder.success(d);
 	}
-	
+
 	@POST
 	@ApiOperation( value = "return dmaap details", notes = "Create a new DMaaP set system wide configuration settings for the *dcaeEnvironment*.  Deprecated with introduction of persistence in 1610.", response = Dmaap.class)
     @ApiResponses( value = {
@@ -79,26 +76,22 @@ public class DmaapResource extends BaseLoggingClass {
         @ApiResponse( code = 400, message = "Error", response = ApiError.class )
     })
 	public Response addDmaap( Dmaap obj ) {
-		ApiService check = new ApiService();	
 
-		try { //check for required fields
-			check.required( "dmaapName", obj.getDmaapName(), "^\\S+$" );  //no white space allowed in dmaapName
-			check.required( "dmaapProvUrl", obj.getDrProvUrl(), "" );
-			check.required( "topicNsRoot", obj.getTopicNsRoot(), "" );
-			check.required( "bridgeAdminTopic", obj.getBridgeAdminTopic(), "" );
+		try {
+			validateRequiredFields(obj);
 		} catch( RequiredFieldException rfe ) {
-			return responseBuilder.error(check.getErr());
+			return responseBuilder.error(rfe.getApiError());
 		}
-	
+
 		Dmaap d =  dmaapService.addDmaap(obj);
 		if ( d == null ) {
 			return responseBuilder.notFound();
 
-		} 
+		}
 
 		return responseBuilder.success(d);
 	}
-	
+
 	@PUT
 	@ApiOperation( value = "return dmaap details", notes = "Update system settings for *dcaeEnvironment*.", response = Dmaap.class)
     @ApiResponses( value = {
@@ -106,23 +99,25 @@ public class DmaapResource extends BaseLoggingClass {
         @ApiResponse( code = 400, message = "Error", response = ApiError.class )
     })
 	public Response updateDmaap(  Dmaap obj ) {
-		ApiService check = new ApiService();
 
-		try { //check for required fields
-			check.required( "dmaapName", obj.getDmaapName(), "^\\S+$" );  //no white space allowed in dmaapName
-			check.required( "dmaapProvUrl", obj.getDrProvUrl(), "" );
-			check.required( "topicNsRoot", obj.getTopicNsRoot(), "" );
-			check.required( "bridgeAdminTopic", obj.getBridgeAdminTopic(), "" );
+		try {
+			validateRequiredFields(obj);
 		} catch( RequiredFieldException rfe ) {
-			return responseBuilder.error(check.getErr());
+			return responseBuilder.error(rfe.getApiError());
 		}
+
 		Dmaap d =  dmaapService.updateDmaap(obj);
 		if ( d != null ) {
 			return responseBuilder.success(d);
 		} else {
 			return responseBuilder.notFound();
-		}	
+		}
+	}
+
+	private void validateRequiredFields(Dmaap obj) throws RequiredFieldException {
+		checker.required( "dmaapName", obj.getDmaapName(), "^\\S+$" );  //no white space allowed in dmaapName
+		checker.required( "dmaapProvUrl", obj.getDrProvUrl());
+		checker.required( "topicNsRoot", obj.getTopicNsRoot());
+		checker.required( "bridgeAdminTopic", obj.getBridgeAdminTopic());
 	}
-	
-	
 }
diff --git a/src/main/java/org/onap/dmaap/dbcapi/resources/FeedResource.java b/src/main/java/org/onap/dmaap/dbcapi/resources/FeedResource.java
index 382d88c..86a79f2 100644
--- a/src/main/java/org/onap/dmaap/dbcapi/resources/FeedResource.java
+++ b/src/main/java/org/onap/dmaap/dbcapi/resources/FeedResource.java
@@ -58,6 +58,7 @@ import org.onap.dmaap.dbcapi.service.FeedService;
 public class FeedResource extends BaseLoggingClass {
 
 	private ResponseBuilder responseBuilder = new ResponseBuilder();
+	private RequiredChecker checker = new RequiredChecker();
 
 	@GET
 	@ApiOperation( value = "return Feed details", 
@@ -96,13 +97,13 @@ public class FeedResource extends BaseLoggingClass {
 		ApiService resp = new ApiService();
 
 		try {
-			resp.required( "feedName", feed.getFeedName(), "");
-			resp.required( "feedVersion", feed.getFeedVersion(), "");
-			resp.required( "owner", feed.getOwner(), "" );
-			resp.required( "asprClassification", feed.getAsprClassification(), "" );
+			checker.required( "feedName", feed.getFeedName());
+			checker.required( "feedVersion", feed.getFeedVersion());
+			checker.required( "owner", feed.getOwner());
+			checker.required( "asprClassification", feed.getAsprClassification());
 		} catch ( RequiredFieldException rfe ) {
-			logger.debug( resp.toString() );
-			return responseBuilder.error(resp.getErr());
+			logger.debug( rfe.getApiError().toString() );
+			return responseBuilder.error(rfe.getApiError());
 		}
 		
 		
@@ -152,10 +153,10 @@ public class FeedResource extends BaseLoggingClass {
 		ApiService resp = new ApiService();
 
 		try {
-			resp.required( "feedId", id, "");
+			checker.required( "feedId", id);
 		} catch ( RequiredFieldException rfe ) {
-			logger.debug( resp.toString() );
-			return responseBuilder.error(resp.getErr());
+			logger.debug( rfe.getApiError().toString() );
+			return responseBuilder.error(rfe.getApiError());
 		}
 
 		Feed nfeed = feedService.getFeed( id, resp.getErr() );
diff --git a/src/main/java/org/onap/dmaap/dbcapi/resources/MR_ClientResource.java b/src/main/java/org/onap/dmaap/dbcapi/resources/MR_ClientResource.java
index a67ac8f..a65007d 100644
--- a/src/main/java/org/onap/dmaap/dbcapi/resources/MR_ClientResource.java
+++ b/src/main/java/org/onap/dmaap/dbcapi/resources/MR_ClientResource.java
@@ -62,6 +62,7 @@ public class MR_ClientResource extends BaseLoggingClass {
 
 	private MR_ClientService mr_clientService = new MR_ClientService();
 	private ResponseBuilder responseBuilder = new ResponseBuilder();
+	private RequiredChecker checker = new RequiredChecker();
 		
 	@GET
 	@ApiOperation( value = "return MR_Client details", 
@@ -95,18 +96,18 @@ public class MR_ClientResource extends BaseLoggingClass {
 		ApiService resp = new ApiService();
 
 		try {
-			resp.required( "fqtn", client.getFqtn(), "");
-			resp.required( "dcaeLocationName", client.getDcaeLocationName(), "");
+			checker.required( "fqtn", client.getFqtn());
+			checker.required( "dcaeLocationName", client.getDcaeLocationName());
 			String s = client.getClientRole();
 			if ( s == null ) {
 				s = client.getClientIdentity();
 			}
-			resp.required( "clientRole or clientIdentity", s, "" );
-			resp.required( "action", client.getAction(), "");
+			checker.required( "clientRole or clientIdentity", s);
+			checker.required( "action", client.getAction());
 
 		} catch ( RequiredFieldException rfe ) {
-			logger.debug( resp.toString() );
-			return responseBuilder.error(resp.getErr());
+			logger.debug( rfe.getApiError().toString() );
+			return responseBuilder.error(rfe.getApiError());
 		}
 		MR_ClusterService clusters = new MR_ClusterService();
 
@@ -161,14 +162,14 @@ public class MR_ClientResource extends BaseLoggingClass {
 		ApiService resp = new ApiService();
 
 		try {
-			resp.required( "fqtn", client.getFqtn(), "");
-			resp.required( "dcaeLocationName", client.getDcaeLocationName(), "");
-			resp.required( "clientRole", client.getClientRole(), "" );
-			resp.required( "action", client.getAction(), "");
+			checker.required( "fqtn", client.getFqtn());
+			checker.required( "dcaeLocationName", client.getDcaeLocationName());
+			checker.required( "clientRole", client.getClientRole());
+			checker.required( "action", client.getAction());
 
 		} catch ( RequiredFieldException rfe ) {
-			logger.debug( resp.toString() );
-			return responseBuilder.error(resp.getErr());
+			logger.debug( rfe.getApiError().toString() );
+			return responseBuilder.error(rfe.getApiError());
 		}
 		client.setMrClientId(clientId);
 		MR_Client nClient = mr_clientService.updateMr_Client(client, resp.getErr() );
@@ -196,10 +197,10 @@ public class MR_ClientResource extends BaseLoggingClass {
 		ApiService resp = new ApiService();
 
 		try {
-			resp.required( "clientId", id, "");
+			checker.required( "clientId", id);
 		} catch ( RequiredFieldException rfe ) {
-			logger.debug( resp.toString() );
-			return responseBuilder.error(resp.getErr());
+			logger.debug( rfe.getApiError().toString() );
+			return responseBuilder.error(rfe.getApiError());
 		}
 		mr_clientService.removeMr_Client(id, true, resp.getErr() );
 		if ( resp.getErr().is2xx()) {
@@ -224,10 +225,10 @@ public class MR_ClientResource extends BaseLoggingClass {
 		ApiService resp = new ApiService();
 
 		try {
-			resp.required( "clientId", id, "");
+			checker.required( "clientId", id);
 		} catch ( RequiredFieldException rfe ) {
-			logger.debug( resp.toString() );
-			return responseBuilder.error(resp.getErr());
+			logger.debug( rfe.getApiError().toString() );
+			return responseBuilder.error(rfe.getApiError());
 		}
 		MR_Client nClient =  mr_clientService.getMr_Client( id, resp.getErr() );
 		if ( resp.getErr().is2xx()) {
diff --git a/src/main/java/org/onap/dmaap/dbcapi/resources/MR_ClusterResource.java b/src/main/java/org/onap/dmaap/dbcapi/resources/MR_ClusterResource.java
index 5d2d379..598fcc2 100644
--- a/src/main/java/org/onap/dmaap/dbcapi/resources/MR_ClusterResource.java
+++ b/src/main/java/org/onap/dmaap/dbcapi/resources/MR_ClusterResource.java
@@ -56,6 +56,7 @@ public class MR_ClusterResource extends BaseLoggingClass {
 
 	private MR_ClusterService mr_clusterService = new MR_ClusterService();
 	private ResponseBuilder responseBuilder = new ResponseBuilder();
+	private RequiredChecker checker = new RequiredChecker();
 		
 	@GET
 	@ApiOperation( value = "return MR_Cluster details", 
@@ -86,10 +87,10 @@ public class MR_ClusterResource extends BaseLoggingClass {
 		ApiService resp = new ApiService();
 
 		try {
-			resp.required( "dcaeLocationName", cluster.getDcaeLocationName(), "" );  
-			resp.required( "fqdn", cluster.getFqdn(), "" );
+			checker.required( "dcaeLocationName", cluster.getDcaeLocationName());
+			checker.required( "fqdn", cluster.getFqdn());
 		} catch( RequiredFieldException rfe ) {
-			return responseBuilder.error(resp.getErr());
+			return responseBuilder.error(rfe.getApiError());
 		}
 		MR_Cluster mrc =  mr_clusterService.addMr_Cluster(cluster, resp.getErr() );
 		if ( mrc != null && mrc.isStatusValid() ) {
@@ -115,10 +116,10 @@ public class MR_ClusterResource extends BaseLoggingClass {
 		ApiService resp = new ApiService();
 
 		try {
-			resp.required( "fqdn", clusterId, "" );
-			resp.required( "dcaeLocationName", cluster.getDcaeLocationName(), "" );  
+			checker.required( "fqdn", clusterId);
+			checker.required( "dcaeLocationName", cluster.getDcaeLocationName());
 		} catch( RequiredFieldException rfe ) {
-			return responseBuilder.error(resp.getErr());
+			return responseBuilder.error(rfe.getApiError());
 		}
 		cluster.setDcaeLocationName(clusterId);
 		MR_Cluster mrc =  mr_clusterService.updateMr_Cluster(cluster, resp.getErr() );
@@ -143,9 +144,9 @@ public class MR_ClusterResource extends BaseLoggingClass {
 		ApiService resp = new ApiService();
 
 		try {
-			resp.required( "fqdn", id, "" );
+			checker.required( "fqdn", id);
 		} catch( RequiredFieldException rfe ) {
-			return responseBuilder.error(resp.getErr());
+			return responseBuilder.error(rfe.getApiError());
 		}
 		mr_clusterService.removeMr_Cluster(id, resp.getErr() );
 		if ( resp.getErr().is2xx()) {
@@ -169,9 +170,9 @@ public class MR_ClusterResource extends BaseLoggingClass {
 		ApiService resp = new ApiService();
 
 		try {
-			resp.required( "dcaeLocationName", id, "" );
+			checker.required( "dcaeLocationName", id);
 		} catch( RequiredFieldException rfe ) {
-			return responseBuilder.error(resp.getErr());
+			return responseBuilder.error(rfe.getApiError());
 		}
 		MR_Cluster mrc =  mr_clusterService.getMr_Cluster( id, resp.getErr() );
 		if ( mrc != null && mrc.isStatusValid() ) {
diff --git a/src/main/java/org/onap/dmaap/dbcapi/resources/RequiredChecker.java b/src/main/java/org/onap/dmaap/dbcapi/resources/RequiredChecker.java
new file mode 100644
index 0000000..36f0215
--- /dev/null
+++ b/src/main/java/org/onap/dmaap/dbcapi/resources/RequiredChecker.java
@@ -0,0 +1,53 @@
+/*
+ * ============LICENSE_START=======================================================
+ * PNF-REGISTRATION-HANDLER
+ * ================================================================================
+ * Copyright (C) 2019 NOKIA 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.onap.dmaap.dbcapi.resources;
+
+import org.onap.dmaap.dbcapi.model.ApiError;
+
+import java.util.regex.Matcher;
+import java.util.regex.Pattern;
+
+import static javax.ws.rs.core.Response.Status.BAD_REQUEST;
+
+public class RequiredChecker {
+
+    public void required(String name, Object val) throws RequiredFieldException {
+        if (val == null) {
+            throw new RequiredFieldException(new ApiError(BAD_REQUEST.getStatusCode(),
+                    "missing required field", name));
+        }
+    }
+
+    public void required(String name, String val, String expr) throws RequiredFieldException {
+
+        required(name, val);
+
+        if (expr != null && !expr.isEmpty()) {
+            Pattern pattern = Pattern.compile(expr);
+            Matcher matcher = pattern.matcher(val);
+            if (!matcher.find()) {
+                throw new RequiredFieldException(new ApiError(BAD_REQUEST.getStatusCode(),
+                        "value '" + val + "' violates regexp check '" + expr + "'", name));
+            }
+        }
+    }
+
+}
diff --git a/src/main/java/org/onap/dmaap/dbcapi/resources/RequiredFieldException.java b/src/main/java/org/onap/dmaap/dbcapi/resources/RequiredFieldException.java
index 74af356..2968d18 100644
--- a/src/main/java/org/onap/dmaap/dbcapi/resources/RequiredFieldException.java
+++ b/src/main/java/org/onap/dmaap/dbcapi/resources/RequiredFieldException.java
@@ -7,9 +7,9 @@
  * 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.
@@ -20,11 +20,27 @@
 
 package org.onap.dmaap.dbcapi.resources;
 
+import org.onap.dmaap.dbcapi.model.ApiError;
+
 public class RequiredFieldException extends Exception {
 
-	/**
-	 * 
-	 */
-	private static final long serialVersionUID = 1L;
+    private static final long serialVersionUID = 2L;
+
+    private final ApiError apiError;
+
+    public RequiredFieldException(ApiError apiError) {
+        super();
+        this.apiError = apiError;
+    }
+
+    public ApiError getApiError() {
+        return apiError;
+    }
 
+    @Override
+    public String toString() {
+        return "RequiredFieldException{" +
+                "apiError=" + apiError +
+                '}';
+    }
 }
diff --git a/src/main/java/org/onap/dmaap/dbcapi/resources/TopicResource.java b/src/main/java/org/onap/dmaap/dbcapi/resources/TopicResource.java
index 4f442c9..96b6a4a 100644
--- a/src/main/java/org/onap/dmaap/dbcapi/resources/TopicResource.java
+++ b/src/main/java/org/onap/dmaap/dbcapi/resources/TopicResource.java
@@ -63,6 +63,7 @@ public class TopicResource extends BaseLoggingClass {
 	private static String defaultReplicationCount;
 	private TopicService mr_topicService = new TopicService();
 	private ResponseBuilder responseBuilder = new ResponseBuilder();
+	private RequiredChecker checker = new RequiredChecker();
 	
 	public TopicResource() {
 		DmaapConfig p = (DmaapConfig)DmaapConfig.getConfig();
@@ -109,12 +110,12 @@ public class TopicResource extends BaseLoggingClass {
 		ApiService check = new ApiService();
 
 		try {
-			check.required( "topicName", topic.getTopicName(), "^\\S+$" );  //no white space allowed in topicName
-			check.required( "topicDescription", topic.getTopicDescription(), "" );
-			check.required( "owner", topic.getOwner(), "" );
+			checker.required( "topicName", topic.getTopicName(), "^\\S+$" );  //no white space allowed in topicName
+			checker.required( "topicDescription", topic.getTopicDescription());
+			checker.required( "owner", topic.getOwner());
 		} catch( RequiredFieldException rfe ) {
-			logger.error("Error", rfe);
-			return responseBuilder.error(check.getErr());
+			logger.error("Error", rfe.getApiError());
+			return responseBuilder.error(rfe.getApiError());
 		}
 		
 		ReplicationType t = topic.getReplicationCase();
@@ -182,10 +183,10 @@ public class TopicResource extends BaseLoggingClass {
 		ApiService check = new ApiService();
 
 		try {
-			check.required( "fqtn", id, "" );
+			checker.required( "fqtn", id);
 		} catch( RequiredFieldException rfe ) {
-			logger.error("Error", rfe);
-			return responseBuilder.error(check.getErr());
+			logger.error("Error", rfe.getApiError());
+			return responseBuilder.error(rfe.getApiError());
 		}
 		
 		mr_topicService.removeTopic(id, check.getErr());
@@ -212,10 +213,10 @@ public class TopicResource extends BaseLoggingClass {
 		ApiService check = new ApiService();
 
 		try {
-			check.required( "topicName", id, "^\\S+$" );  //no white space allowed in topicName
+			checker.required( "topicName", id, "^\\S+$" );  //no white space allowed in topicName
 		} catch( RequiredFieldException rfe ) {
-			logger.error("Error", rfe);
-			return responseBuilder.error(check.getErr());
+			logger.error("Error", rfe.getApiError());
+			return responseBuilder.error(rfe.getApiError());
 		}
 		Topic mrc =  mr_topicService.getTopic( id, check.getErr() );
 		if ( mrc == null ) {
diff --git a/src/main/java/org/onap/dmaap/dbcapi/service/ApiService.java b/src/main/java/org/onap/dmaap/dbcapi/service/ApiService.java
index b2eee6f..35e61db 100644
--- a/src/main/java/org/onap/dmaap/dbcapi/service/ApiService.java
+++ b/src/main/java/org/onap/dmaap/dbcapi/service/ApiService.java
@@ -24,9 +24,6 @@ import static com.att.eelf.configuration.Configuration.MDC_KEY_REQUEST_ID;
 import static com.att.eelf.configuration.Configuration.MDC_PARTNER_NAME;
 import static com.att.eelf.configuration.Configuration.MDC_SERVICE_NAME;
 
-import java.util.regex.Matcher;
-import java.util.regex.Pattern;
-import javax.ws.rs.core.Response.Status;
 import javax.xml.bind.DatatypeConverter;
 import org.onap.dmaap.dbcapi.aaf.DmaapPerm;
 import org.onap.dmaap.dbcapi.authentication.ApiPolicy;
@@ -34,7 +31,6 @@ import org.onap.dmaap.dbcapi.authentication.AuthenticationErrorException;
 import org.onap.dmaap.dbcapi.logging.BaseLoggingClass;
 import org.onap.dmaap.dbcapi.model.ApiError;
 import org.onap.dmaap.dbcapi.model.Dmaap;
-import org.onap.dmaap.dbcapi.resources.RequiredFieldException;
 import org.onap.dmaap.dbcapi.util.DmaapConfig;
 import org.onap.dmaap.dbcapi.util.RandomString;
 import org.slf4j.MDC;
@@ -109,37 +105,9 @@ public class ApiService extends BaseLoggingClass {
         this.err = err;
     }
 
-
-    // test for presence of a required field
-    public void required(String name, Object val, String expr) throws RequiredFieldException {
-        err.setCode(0);
-        if (val == null) {
-            err.setCode(Status.BAD_REQUEST.getStatusCode());
-            err.setMessage("missing required field");
-            err.setFields(name);
-            throw new RequiredFieldException();
-        }
-        if (expr != null && !expr.isEmpty()) {
-            Pattern pattern = Pattern.compile(expr);
-            Matcher matcher = pattern.matcher((CharSequence) val);
-            if (!matcher.find()) {
-                err.setCode(Status.BAD_REQUEST.getStatusCode());
-                err.setMessage("value '" + val + "' violates regexp check '" + expr + "'");
-                err.setFields(name);
-                throw new RequiredFieldException();
-            }
-        }
-    }
-
-    // utility to serialize ApiErr object
-    public String toString() {
-        return String.format("code=%d msg=%s fields=%s", err.getCode(), err.getMessage(), err.getFields());
-    }
-
-
-    public void setCode(int statusCode) {
-        err.setCode(statusCode);
-    }
+	public void setCode(int statusCode) {
+		err.setCode(statusCode);
+	}
 
 
     public void setMessage(String string) {
@@ -147,21 +115,11 @@ public class ApiService extends BaseLoggingClass {
     }
 
 
-    public void setFields(String string) {
-        err.setFields(string);
-    }
+	public void setFields(String string) {
+		err.setFields(string);
+	}
 
-    public void checkAuthorization(String auth, String uriPath, String httpMethod)
-        throws AuthenticationErrorException, Exception {
-        authorization = auth;
-        setUriFromPath(uriPath);
-        method = httpMethod;
-
-        checkAuthorization();
-    }
-
-
-    public void checkAuthorization() throws AuthenticationErrorException, Exception {
+    public void checkAuthorization() throws Exception {
 
         MDC.put(MDC_KEY_REQUEST_ID, requestId);
 
@@ -217,12 +175,6 @@ public class ApiService extends BaseLoggingClass {
             throw ae;
 
         }
-
-
-    }
-
-    public String getRequestId() {
-        return requestId;
     }
 
     public ApiService setRequestId(String requestId) {
@@ -236,3 +188,4 @@ public class ApiService extends BaseLoggingClass {
         return this;
     }
 }
+
diff --git a/src/test/java/org/onap/dmaap/dbcapi/resources/RequiredCheckerTest.java b/src/test/java/org/onap/dmaap/dbcapi/resources/RequiredCheckerTest.java
new file mode 100644
index 0000000..f07058b
--- /dev/null
+++ b/src/test/java/org/onap/dmaap/dbcapi/resources/RequiredCheckerTest.java
@@ -0,0 +1,86 @@
+/*
+ * ============LICENSE_START=======================================================
+ * PNF-REGISTRATION-HANDLER
+ * ================================================================================
+ * Copyright (C) 2019 NOKIA 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.onap.dmaap.dbcapi.resources;
+
+import org.hamcrest.BaseMatcher;
+import org.hamcrest.Description;
+import org.junit.Rule;
+import org.junit.Test;
+import org.junit.rules.ExpectedException;
+import org.onap.dmaap.dbcapi.model.ApiError;
+
+import static javax.ws.rs.core.Response.Status.BAD_REQUEST;
+import static org.junit.Assert.fail;
+
+public class RequiredCheckerTest {
+
+    private static final String NAME = "field_name";
+    @Rule
+    public ExpectedException thrown = ExpectedException.none();
+    private RequiredChecker requiredChecker = new RequiredChecker();
+
+
+    @Test
+    public void required_shouldThrowExceptionWhenObjectIsNull() throws RequiredFieldException {
+        thrown.expect(RequiredFieldException.class);
+        thrown.expect(new ApiErrorMatcher(new ApiError(BAD_REQUEST.getStatusCode(),
+                "missing required field", NAME)));
+
+        requiredChecker.required(NAME, null);
+    }
+
+    @Test
+    public void required_shouldThrowExceptionWhenRegexValidationFailed() throws RequiredFieldException {
+        thrown.expect(RequiredFieldException.class);
+        thrown.expect(new ApiErrorMatcher(new ApiError(BAD_REQUEST.getStatusCode(),
+                "value 'with white space' violates regexp check '^\\S+$'", NAME)));
+
+        requiredChecker.required(NAME, "with white space", "^\\S+$");
+    }
+
+    @Test
+    public void required_shouldPassValidation() {
+        try {
+            requiredChecker.required(NAME, "value", "^\\S+$");
+        } catch (RequiredFieldException e) {
+            fail("No exception should be thrown");
+        }
+    }
+
+    class ApiErrorMatcher extends BaseMatcher {
+
+        private final ApiError expectedApiEror;
+
+        ApiErrorMatcher(ApiError expectedApiEror) {
+            this.expectedApiEror = expectedApiEror;
+        }
+
+        @Override
+        public boolean matches(Object exception) {
+            return expectedApiEror.equals(((RequiredFieldException) exception).getApiError());
+        }
+
+        @Override
+        public void describeTo(Description description) {
+            description.appendText("Following ApiError is expected: ").appendValue(expectedApiEror);
+        }
+    }
+}
\ No newline at end of file
diff --git a/src/test/java/org/onap/dmaap/dbcapi/service/ApiServiceTest.java b/src/test/java/org/onap/dmaap/dbcapi/service/ApiServiceTest.java
index 33cce9d..dccfadf 100644
--- a/src/test/java/org/onap/dmaap/dbcapi/service/ApiServiceTest.java
+++ b/src/test/java/org/onap/dmaap/dbcapi/service/ApiServiceTest.java
@@ -59,22 +59,4 @@ public class ApiServiceTest {
 		rh.reflect( "org.onap.dmaap.dbcapi.service.ApiService", "set", v );
 
 	}
-
-	@Test
-	public void test3() {
-		ApiService nd = new ApiService();
-		nd.setAuth( "auth" );
-		try {
-			nd.required( "aName", null, "anExpr" );
-		} catch ( RequiredFieldException rfe ) {
-		}
-		try {
-			nd.checkAuthorization( "authval", "/uri/Path", "GET" );
-			nd.checkAuthorization();
-		} catch ( AuthenticationErrorException aee ) {
-		} catch ( Exception e ) {
-		}
-	}
-
-
 }