fix some sdnr sonar bugs

sonar fixes for some sdnr components

Issue-ID: SDNC-1590
Change-Id: I02e44b6f5477bcd0490c3499caf20228eb9772ed
Signed-off-by: Michael DÜrre <michael.duerre@highstreet-technologies.com>

7 files changed, 96 insertions, 93 deletions

diff --git a/sdnr/wt/data-provider/provider/src/main/java/org/onap/ccsdk/features/sdnr/wt/dataprovider/database/elasticsearch/EsDataObjectReaderWriter2.java b/sdnr/wt/data-provider/provider/src/main/java/org/onap/ccsdk/features/sdnr/wt/dataprovider/database/elasticsearch/EsDataObjectReaderWriter2.java
index a86ecdde1..cb0f22da1 100644
--- a/sdnr/wt/data-provider/provider/src/main/java/org/onap/ccsdk/features/sdnr/wt/dataprovider/database/elasticsearch/EsDataObjectReaderWriter2.java
+++ b/sdnr/wt/data-provider/provider/src/main/java/org/onap/ccsdk/features/sdnr/wt/dataprovider/database/elasticsearch/EsDataObjectReaderWriter2.java
@@ -53,7 +53,7 @@ import org.slf4j.LoggerFactory;
  */
 public class EsDataObjectReaderWriter2<T extends DataObject> {
 
-    private final Logger LOG = LoggerFactory.getLogger(EsDataObjectReaderWriter2.class);
+    private static final Logger LOG = LoggerFactory.getLogger(EsDataObjectReaderWriter2.class);
 
     /** Typename for elastic search data schema **/
     private String dataTypeName;
@@ -202,7 +202,7 @@ public class EsDataObjectReaderWriter2<T extends DataObject> {
      *
      * @param writeInterfaceClazz
      */
-    public EsDataObjectReaderWriter2<T> setWriteInterface(@Nonnull Class<? extends DataObject> writeInterfaceClazz) {
+    public EsDataObjectReaderWriter2<T> setWriteInterface(Class<? extends DataObject> writeInterfaceClazz) {
         LOG.debug("Set write interface to {}", writeInterfaceClazz);
         if (writeInterfaceClazz == null) {
             throw new IllegalArgumentException("Null not allowed here.");
@@ -359,7 +359,7 @@ public class EsDataObjectReaderWriter2<T extends DataObject> {
         if(this.doFullsizeRequest) {
             query.doFullsizeRequest();
         }
-        SearchResult<T> res = new SearchResult<T>();
+        SearchResult<T> res = new SearchResult<>();
         SearchResult<SearchHit> result;
         List<SearchHit> hits;
         if (query != null) {
diff --git a/sdnr/wt/data-provider/provider/src/main/java/org/onap/ccsdk/features/sdnr/wt/dataprovider/database/elasticsearch/data/rpctypehelper/QueryByFilter.java b/sdnr/wt/data-provider/provider/src/main/java/org/onap/ccsdk/features/sdnr/wt/dataprovider/database/elasticsearch/data/rpctypehelper/QueryByFilter.java
index eef61e09c..69f9bcc29 100644
--- a/sdnr/wt/data-provider/provider/src/main/java/org/onap/ccsdk/features/sdnr/wt/dataprovider/database/elasticsearch/data/rpctypehelper/QueryByFilter.java
+++ b/sdnr/wt/data-provider/provider/src/main/java/org/onap/ccsdk/features/sdnr/wt/dataprovider/database/elasticsearch/data/rpctypehelper/QueryByFilter.java
@@ -96,10 +96,10 @@ public class QueryByFilter {
         if (fromPage < 0 || pageSize > 10000)
             throw new IllegalArgumentException("mismatching input parameters. From:" + fromPage + " size:" + pageSize);
 
-        filterList = YangHelper.getList(input.getFilter());
+        filterList = input == null ? null : YangHelper.getList(input.getFilter());
         if (filterList == null)
             filterList = emptyFilterList;
-        sortOrder = YangHelper.getList(input.getSortorder());
+        sortOrder = input == null ? null : YangHelper.getList(input.getSortorder());
         if (sortOrder == null)
             sortOrder = emptySortOrderList;
 
@@ -167,7 +167,7 @@ public class QueryByFilter {
      * Private and static implementations
      */
     private static QueryBuilder setSortOrder(QueryBuilder query, @Nullable List<Sortorder> sortorder, String prefix) {
-        if (sortorder != null && sortorder.size() > 0) {
+        if (sortorder != null && !sortorder.isEmpty()) {
             for (Sortorder so : sortorder) {
                 query.sort(handlePrefix(prefix, so.getProperty()), convert(so.getSortorder()));
             }
@@ -179,7 +179,7 @@ public class QueryByFilter {
         return sortOrder == SortOrder.Ascending
                 ? org.onap.ccsdk.features.sdnr.wt.common.database.queries.SortOrder.ASCENDING
                 : org.onap.ccsdk.features.sdnr.wt.common.database.queries.SortOrder.DESCENDING;
-    };
+    }
 
     private static Sortorder getSortOrder(@Nullable List<Sortorder> list, String prop) {
         if (list == null) {
@@ -353,7 +353,7 @@ public class QueryByFilter {
     }
 
     private static List<String> collectValues(Filter filter) {
-        List<String> values = new ArrayList<String>();
+        List<String> values = new ArrayList<>();
         if (filter.getFiltervalue() != null) {
             values.add(filter.getFiltervalue());
         }
@@ -364,7 +364,7 @@ public class QueryByFilter {
     }
 
     private static QueryBuilder fromFilter(@Nullable List<Filter> filters, String prefix) {
-        if (filters == null || filters.size() == 0) {
+        if (filters == null || filters.isEmpty()) {
             return QueryBuilders.matchAllQuery();
 
         } else if (filters.size() == 1) {
@@ -399,7 +399,6 @@ public class QueryByFilter {
                         tmpQuery.should(getSinglePropertyQuery(p, v, prefix));
                     }
                     query.must(tmpQuery);
-                    tmpQuery = QueryBuilders.boolQuery();
                 }
             }
             LOG.trace("Query result. {}", query.toJSON());
diff --git a/sdnr/wt/data-provider/provider/src/main/java/org/onap/ccsdk/features/sdnr/wt/dataprovider/http/DataTreeHttpServlet.java b/sdnr/wt/data-provider/provider/src/main/java/org/onap/ccsdk/features/sdnr/wt/dataprovider/http/DataTreeHttpServlet.java
index 115ff4f40..3c4a7621b 100644
--- a/sdnr/wt/data-provider/provider/src/main/java/org/onap/ccsdk/features/sdnr/wt/dataprovider/http/DataTreeHttpServlet.java
+++ b/sdnr/wt/data-provider/provider/src/main/java/org/onap/ccsdk/features/sdnr/wt/dataprovider/http/DataTreeHttpServlet.java
@@ -29,6 +29,7 @@ import java.io.UnsupportedEncodingException;
 import java.net.URLDecoder;
 import java.util.ArrayList;
 import java.util.List;
+import java.util.Optional;
 import java.util.regex.Matcher;
 import java.util.regex.Pattern;
 import javax.servlet.ServletException;
@@ -70,9 +71,9 @@ public class DataTreeHttpServlet extends HttpServlet {
         String body = null;
         StringBuilder stringBuilder = new StringBuilder();
         BufferedReader bufferedReader = null;
+        IOException toThrow = null;
+        try (InputStream inputStream = request.getInputStream()) {
 
-        try {
-            InputStream inputStream = request.getInputStream();
             if (inputStream != null) {
                 bufferedReader = new BufferedReader(new InputStreamReader(inputStream));
                 char[] charBuffer = new char[128];
@@ -84,17 +85,20 @@ public class DataTreeHttpServlet extends HttpServlet {
                 stringBuilder.append("");
             }
         } catch (IOException ex) {
-            throw ex;
+            toThrow = ex;
         } finally {
             if (bufferedReader != null) {
                 try {
                     bufferedReader.close();
                 } catch (IOException ex) {
-                    throw ex;
+                    LOG.debug("problem closing reader:", ex);
+                    toThrow = ex;
                 }
             }
         }
-
+        if (toThrow != null) {
+            throw toThrow;
+        }
         body = stringBuilder.toString();
         return body;
     }
@@ -164,13 +168,16 @@ public class DataTreeHttpServlet extends HttpServlet {
         final String regex = "^\\/tree\\/read-(.*)-tree\\/?(.*)$";
         final Pattern pattern = Pattern.compile(regex);
         final Matcher matcher = pattern.matcher(uri);
-        Entity e = null;
         if (matcher.find() && matcher.groupCount() > 0) {
             try {
-                e = Entity.forName(matcher.group(1)).get();
-                return new EntityWithTree(e, matcher.groupCount() > 1 ? matcher.group(2) : null);
+                Optional<Entity> oe = Entity.forName(matcher.group(1));
+                if (oe.isPresent()) {
+                    return new EntityWithTree(oe.get(), matcher.groupCount() > 1 ? matcher.group(2) : null);
+                } else {
+                    LOG.warn("unable to find entity for name {}", matcher.group(1));
+                }
             } catch (Exception e2) {
-                LOG.warn("unable to parse {} into entity: {}", matcher.group(2), e2);
+                LOG.warn("unable to parse {} into entity: ", matcher.group(2), e2);
             }
         }
         return null;
@@ -182,7 +189,7 @@ public class DataTreeHttpServlet extends HttpServlet {
         try {
             resp.getWriter().write(data.toJSON());
         } catch (IOException e) {
-            LOG.warn("problem sending response: {}", e);
+            LOG.warn("problem sending response: ", e);
         }
     }
 
@@ -196,14 +203,14 @@ public class DataTreeHttpServlet extends HttpServlet {
         }
 
         /**
-         *
-         * @param e database enttity to access
-         * @param tree tree description
-         *   e.g. nodeA           => tree entry for node-id=nodeA
-         *        nodeA/key0      => tree entry for node-id=nodeA and uuid=key0 and tree-level=0
-         *        nodeA/key0/key1 => tree entry for node-id=nodeA and uuid=key1 and tree-level=1
-         *
-         */
+        *
+        * @param e database enttity to access
+        * @param tree tree description
+        *   e.g. nodeA           => tree entry for node-id=nodeA
+        *        nodeA/key0      => tree entry for node-id=nodeA and uuid=key0 and tree-level=0
+        *        nodeA/key0/key1 => tree entry for node-id=nodeA and uuid=key1 and tree-level=1
+        *
+        */
         public EntityWithTree(Entity e, String tree) {
             this.entity = e;
             if (tree != null) {
diff --git a/sdnr/wt/data-provider/provider/src/main/java/org/onap/ccsdk/features/sdnr/wt/dataprovider/http/UserdataHttpServlet.java b/sdnr/wt/data-provider/provider/src/main/java/org/onap/ccsdk/features/sdnr/wt/dataprovider/http/UserdataHttpServlet.java
index 09a81c381..b51d2a6df 100644
--- a/sdnr/wt/data-provider/provider/src/main/java/org/onap/ccsdk/features/sdnr/wt/dataprovider/http/UserdataHttpServlet.java
+++ b/sdnr/wt/data-provider/provider/src/main/java/org/onap/ccsdk/features/sdnr/wt/dataprovider/http/UserdataHttpServlet.java
@@ -43,7 +43,7 @@ public class UserdataHttpServlet extends HttpServlet {
     private static final String REGEX = "^\\/userdata[\\/]?([a-zA-Z0-9]+)?$";
     private static final Pattern PATTERN = Pattern.compile(REGEX);
     private static final String JWT_PAYLOAD_USERNAME_PROPERTYKEY = "sub";
-    private HtUserdataManager dbUserManager;
+    private static HtUserdataManager dbUserManager;
 
     @Override
     protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
@@ -91,47 +91,46 @@ public class UserdataHttpServlet extends HttpServlet {
 
     private void handleGetRequest(HttpServletRequest req, HttpServletResponse resp, String key) {
         final String username = this.getUsername(req);
-        if(username==null) {
+        if (username == null) {
             resp.setStatus(HttpServletResponse.SC_UNAUTHORIZED);
             return;
         }
         sendJsonResponse(resp,
-                key == null ? this.dbUserManager.getUserdata(username) : this.dbUserManager.getUserdata(username, key));
+                key == null ? dbUserManager.getUserdata(username) : dbUserManager.getUserdata(username, key));
     }
 
 
     private void handlePutRequest(HttpServletRequest req, HttpServletResponse resp, String data, String key) {
         final String username = this.getUsername(req);
-        if(username==null) {
+        if (username == null) {
             resp.setStatus(HttpServletResponse.SC_UNAUTHORIZED);
             return;
         }
-        boolean success = key == null ? this.dbUserManager.setUserdata(username, data)
-                : this.dbUserManager.setUserdata(username, key, data);
+        boolean success = key == null ? dbUserManager.setUserdata(username, data)
+                : dbUserManager.setUserdata(username, key, data);
         resp.setStatus(success ? HttpServletResponse.SC_OK : HttpServletResponse.SC_INTERNAL_SERVER_ERROR);
     }
 
     private void handleDeleteRequest(HttpServletRequest req, HttpServletResponse resp, String key) {
         final String username = this.getUsername(req);
-        if(username==null) {
+        if (username == null) {
             resp.setStatus(HttpServletResponse.SC_UNAUTHORIZED);
             return;
         }
-        boolean success = key == null ? this.dbUserManager.removeUserdata(username)
-                : this.dbUserManager.removeUserdata(username, key);
+        boolean success =
+                key == null ? dbUserManager.removeUserdata(username) : dbUserManager.removeUserdata(username, key);
         resp.setStatus(success ? HttpServletResponse.SC_OK : HttpServletResponse.SC_INTERNAL_SERVER_ERROR);
     }
 
     private String getUsername(HttpServletRequest req) {
         final String authHeader = req.getHeader("Authorization");
-        if(authHeader==null) {
+        if (authHeader == null) {
             return null;
         }
         String username = null;
-        if(authHeader.startsWith("Basic")) {
+        if (authHeader.startsWith("Basic")) {
             username = BaseHTTPClient.decodeBasicAuthHeaderUsername(authHeader);
-        }
-        else if(authHeader.startsWith("Bearer")) {
+        } else if (authHeader.startsWith("Bearer")) {
             username = decodeJWTPayloadUsername(authHeader, JWT_PAYLOAD_USERNAME_PROPERTYKEY);
         }
         return username;
@@ -139,16 +138,16 @@ public class UserdataHttpServlet extends HttpServlet {
 
     public static String decodeJWTPayloadUsername(String authHeader, String key) {
         String username = null;
-        if(authHeader.startsWith("Bearer")) {
+        if (authHeader.startsWith("Bearer")) {
             authHeader = authHeader.substring(7);
         }
         String[] tmp = authHeader.split("\\.");
-        if(tmp.length==3) {
+        if (tmp.length == 3) {
             final String decoded = new String(Base64.getDecoder().decode(tmp[1]));
-            JSONObject o  = new JSONObject(decoded);
-            if(o.has(key)) {
+            JSONObject o = new JSONObject(decoded);
+            if (o.has(key)) {
                 username = o.getString(key);
-                if(username!=null && username.contains("@")) {
+                if (username != null && username.contains("@")) {
                     username = username.split("@")[0];
                 }
             }
@@ -168,8 +167,8 @@ public class UserdataHttpServlet extends HttpServlet {
 
     }
 
-    public void setDatabaseClient(HtUserdataManager dbUserManager) {
-        this.dbUserManager = dbUserManager;
+    public void setDatabaseClient(HtUserdataManager dbMgr) {
+        dbUserManager = dbMgr;
     }
 
 }
diff --git a/sdnr/wt/data-provider/provider/src/main/java/org/onap/ccsdk/features/sdnr/wt/dataprovider/http/about/AboutHttpServlet.java b/sdnr/wt/data-provider/provider/src/main/java/org/onap/ccsdk/features/sdnr/wt/dataprovider/http/about/AboutHttpServlet.java
index 64b5fab9f..cd75ca2a8 100644
--- a/sdnr/wt/data-provider/provider/src/main/java/org/onap/ccsdk/features/sdnr/wt/dataprovider/http/about/AboutHttpServlet.java
+++ b/sdnr/wt/data-provider/provider/src/main/java/org/onap/ccsdk/features/sdnr/wt/dataprovider/http/about/AboutHttpServlet.java
@@ -34,8 +34,6 @@ import javax.servlet.http.HttpServlet;
 import javax.servlet.http.HttpServletRequest;
 import javax.servlet.http.HttpServletResponse;
 import org.apache.http.HttpHeaders;
-//import org.apache.karaf.bundle.core.BundleInfo;
-//import org.apache.karaf.bundle.core.BundleService;
 import org.onap.ccsdk.features.sdnr.wt.common.Resources;
 import org.onap.ccsdk.features.sdnr.wt.common.file.PomFile;
 import org.onap.ccsdk.features.sdnr.wt.common.file.PomPropertiesFile;
@@ -83,8 +81,7 @@ public class AboutHttpServlet extends HttpServlet {
     private final Map<Integer, String> BUNDLESTATE_LUT;
     private final Map<String, String> data;
     private final String readmeContent;
-    //	private BundleService bundleService;
-    private String jsonContent;
+    private final String jsonContent;
 
 
     public AboutHttpServlet() {
@@ -114,10 +111,6 @@ public class AboutHttpServlet extends HttpServlet {
         return def;
     }
 
-    //	public void setBundleService(BundleService bundleService) {
-    //		this.bundleService = bundleService;
-    //	}
-
     /**
      * collect static versioning data
      */
@@ -152,22 +145,11 @@ public class AboutHttpServlet extends HttpServlet {
             resp.setStatus(HttpServletResponse.SC_OK);
             resp.setContentLength(output.length);
             resp.setContentType(ctype.getMimeType());
-            ServletOutputStream os = null;
-            try {
-                os = resp.getOutputStream();
+            try (ServletOutputStream os = resp.getOutputStream()) {
                 os.write(output);
             } catch (IOException e) {
                 LOG.warn("problem writing response for {}: {}", uri, e);
-            } finally {
-                if (os != null) {
-                    try {
-                        os.close();
-                    } catch (IOException e) {
-                        LOG.warn("problem closing response stream: {}", e);
-                    }
-                }
             }
-
         } else {
             this.doGetFile(uri, resp);
         }
@@ -183,7 +165,7 @@ public class AboutHttpServlet extends HttpServlet {
         if (content == null) {
             return def;
         }
-        String lines[] = content.split("\n");
+        String[] lines = content.split("\n");
         for (String line : lines) {
             if (line.startsWith("git.commit.id")) {
                 def = line.substring("git.commit.id=".length());
@@ -207,7 +189,7 @@ public class AboutHttpServlet extends HttpServlet {
             this.data.put(PLACEHOLDER_KARAF_INFO, SystemInfo.get());
             this.data.put(PLACEHOLDER_DEVICEMANAGER_TABLE, this.getDevicemanagerBundles(ctype));
         } catch (Exception e) {
-            LOG.warn("problem collecting system data: {}", e);
+            LOG.warn("problem collecting system data: ", e);
         }
     }
 
@@ -228,7 +210,7 @@ public class AboutHttpServlet extends HttpServlet {
             Attributes attr = manifest.getMainAttributes();
             return attr.getValue(key);
         } catch (IOException e) {
-            LOG.warn("problem reading manifest: {}", e);
+            LOG.warn("problem reading manifest: ", e);
         }
         return null;
 
@@ -282,12 +264,12 @@ public class AboutHttpServlet extends HttpServlet {
         BundleContext context = thisbundle == null ? null : thisbundle.getBundleContext();
         if (context == null) {
             LOG.debug("no bundle context available");
-            return ctype==ContentType.MARKDOWN?"":"[]";
+            return ctype == ContentType.MARKDOWN ? "" : "[]";
         }
         Bundle[] bundles = context.getBundles();
         if (bundles == null || bundles.length <= 0) {
             LOG.debug("no bundles found");
-            return ctype==ContentType.MARKDOWN?NO_DEVICEMANAGERS_RUNNING_MESSAGE:"[]";
+            return ctype == ContentType.MARKDOWN ? NO_DEVICEMANAGERS_RUNNING_MESSAGE : "[]";
         }
         LOG.debug("found {} bundles", bundles.length);
         MarkdownTable table = new MarkdownTable();
@@ -302,10 +284,10 @@ public class AboutHttpServlet extends HttpServlet {
                 continue;
             }
             table.addRow(new String[] {String.valueOf(bundle.getBundleId()), bundle.getVersion().toString(), name,
-                    BUNDLESTATE_LUT.getOrDefault(bundle.getState(), "unknown")});
+                    BUNDLESTATE_LUT.getOrDefault(bundle.getState(), UNKNOWN)});
 
         }
-        return ctype==ContentType.MARKDOWN?table.toMarkDown():table.toJson();
+        return ctype == ContentType.MARKDOWN ? table.toMarkDown() : table.toJson();
     }
 
     /**
@@ -329,7 +311,7 @@ public class AboutHttpServlet extends HttpServlet {
             try {
                 resp.getOutputStream().write(data);
             } catch (IOException e) {
-                LOG.debug("unable to send data : {}", e);
+                LOG.debug("unable to send data: ", e);
             }
         }
 
@@ -352,7 +334,7 @@ public class AboutHttpServlet extends HttpServlet {
             case "bmp":
                 return "image/" + ext;
             case "json":
-                return "application/json";
+                return MIMETYPE_JSON;
             case "html":
             case "htm":
                 return "text/html";
@@ -382,7 +364,7 @@ public class AboutHttpServlet extends HttpServlet {
      */
     private String render(ContentType ctype, String content) {
         if (content == null) {
-            content = ctype==ContentType.MARKDOWN? this.readmeContent:this.jsonContent;
+            content = ctype == ContentType.MARKDOWN ? this.readmeContent : this.jsonContent;
         }
         if (content == null) {
             return null;
diff --git a/sdnr/wt/data-provider/provider/src/main/java/org/onap/ccsdk/features/sdnr/wt/dataprovider/http/about/MarkdownTable.java b/sdnr/wt/data-provider/provider/src/main/java/org/onap/ccsdk/features/sdnr/wt/dataprovider/http/about/MarkdownTable.java
index 1580a0fe3..e13ca8203 100644
--- a/sdnr/wt/data-provider/provider/src/main/java/org/onap/ccsdk/features/sdnr/wt/dataprovider/http/about/MarkdownTable.java
+++ b/sdnr/wt/data-provider/provider/src/main/java/org/onap/ccsdk/features/sdnr/wt/dataprovider/http/about/MarkdownTable.java
@@ -47,10 +47,20 @@ public class MarkdownTable {
         this.rows.add(values);
     }
 
+    private int getColNumbers() {
+        int cols = 0;
+        if (this.columns != null) {
+            cols = this.columns.length;
+        } else {
+            cols = !this.rows.isEmpty() ? this.rows.get(0).length : 0;
+        }
+        return cols;
+    }
+
     public String toMarkDown() {
         StringBuilder sb = new StringBuilder();
-        final int cols =
-                this.columns != null ? this.columns.length : this.rows.size() > 0 ? this.rows.get(0).length : 0;
+
+        final int cols = this.getColNumbers();
         if (cols > 0) {
             sb.append("|");
             for (int i = 0; i < cols; i++) {
@@ -75,9 +85,8 @@ public class MarkdownTable {
 
     public String toJson() {
         JSONArray a = new JSONArray();
-        final int cols =
-                this.columns != null ? this.columns.length : this.rows.size() > 0 ? this.rows.get(0).length : 0;
-        if (cols > 0) {
+        final int cols = this.getColNumbers();
+        if (cols > 0 && this.columns!=null) {
             for (String[] row : this.rows) {
                 JSONObject o = new JSONObject();
                 for (int i = 0; i < cols; i++) {
diff --git a/sdnr/wt/data-provider/provider/src/main/java/org/onap/ccsdk/features/sdnr/wt/dataprovider/impl/DataProviderServiceImpl.java b/sdnr/wt/data-provider/provider/src/main/java/org/onap/ccsdk/features/sdnr/wt/dataprovider/impl/DataProviderServiceImpl.java
index 2bf67fde9..5a99c8ab3 100644
--- a/sdnr/wt/data-provider/provider/src/main/java/org/onap/ccsdk/features/sdnr/wt/dataprovider/impl/DataProviderServiceImpl.java
+++ b/sdnr/wt/data-provider/provider/src/main/java/org/onap/ccsdk/features/sdnr/wt/dataprovider/impl/DataProviderServiceImpl.java
@@ -45,6 +45,7 @@ import org.onap.ccsdk.features.sdnr.wt.dataprovider.model.HtUserdataManager;
 import org.onap.ccsdk.features.sdnr.wt.dataprovider.model.IEsConfig;
 import org.onap.ccsdk.features.sdnr.wt.dataprovider.model.SdnrDbType;
 import org.opendaylight.mdsal.binding.api.DataBroker;
+import org.opendaylight.mdsal.binding.api.ReadTransaction;
 import org.opendaylight.mdsal.binding.api.RpcProviderService;
 import org.opendaylight.mdsal.common.api.LogicalDatastoreType;
 import org.opendaylight.yang.gen.v1.urn.opendaylight.netconf.keystore.rev171017.Keystore;
@@ -136,6 +137,7 @@ public class DataProviderServiceImpl implements DataProviderService, AutoCloseab
     private final HtUserdataManager dbUserManager;
     private final DataBroker dataBroker;
     private final MsServlet mediatorServerServlet;
+
     public DataProviderServiceImpl(final RpcProviderService rpcProviderService, MsServlet mediatorServerServlet,
             DataBroker dataBroker) throws Exception {
         this.configuration = new ConfigurationFileRepresentation(CONFIGURATIONFILE);
@@ -151,7 +153,7 @@ public class DataProviderServiceImpl implements DataProviderService, AutoCloseab
         mediatorServerServlet.setDataProvider(this.dataProvider.getHtDatabaseMediatorServer());
         this.dbUserManager = new HtUserdataManagerImpl(this.dataProvider.getRawClient());
         // Register ourselves as the REST API RPC implementation
-        LOG.info("Register RPC Service " + DataProviderServiceImpl.class.getSimpleName());
+        LOG.info("Register RPC Service {}", DataProviderServiceImpl.class.getSimpleName());
         this.rpcReg = rpcProviderService.registerRpcImplementation(DataProviderService.class, this);
     }
 
@@ -425,11 +427,15 @@ public class DataProviderServiceImpl implements DataProviderService, AutoCloseab
 
     private ReadTlsKeyEntryOutputBuilder readTlsKeys(ReadTlsKeyEntryInput input) {
         Optional<Keystore> result = Optional.empty();
-        try {
-            result = this.dataBroker.newReadOnlyTransaction().read(LogicalDatastoreType.CONFIGURATION, KEYSTORE_IIF)
-                    .get();
-        } catch (InterruptedException | ExecutionException e) {
+        try (ReadTransaction transaction = this.dataBroker.newReadOnlyTransaction()) {
+            result = transaction.read(LogicalDatastoreType.CONFIGURATION, KEYSTORE_IIF).get();
+        } catch (ExecutionException e) {
             LOG.warn("problem reading netconf-keystore: ", e);
+
+        } catch (InterruptedException e) {
+            LOG.warn("Interrupted!", e);
+            // Restore interrupted state...
+            Thread.currentThread().interrupt();
         }
         ReadTlsKeyEntryOutputBuilder output = new ReadTlsKeyEntryOutputBuilder();
         if (result.isEmpty()) {
@@ -439,11 +445,12 @@ public class DataProviderServiceImpl implements DataProviderService, AutoCloseab
         if (keyCredential == null) {
             return output.setData(Arrays.asList()).setPagination(EMPTY_PAGINATION);
         }
-        long pageNum = input.getPagination() == null ? DEFAULT_PAGE
-                : input.getPagination().getPage() == null ? DEFAULT_PAGE : input.getPagination().getPage().longValue();
-        long size = input.getPagination() == null ? DEFAULT_PAGESIZE
-                : input.getPagination().getSize() == null ? DEFAULT_PAGESIZE
-                        : input.getPagination().getSize().longValue();
+        org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.data.provider.rev201110.entity.input.Pagination pagination =
+                input.getPagination();
+        long pageNum = pagination == null ? DEFAULT_PAGE
+                : pagination.getPage() == null ? DEFAULT_PAGE : pagination.getPage().longValue();
+        long size = pagination == null ? DEFAULT_PAGESIZE
+                : pagination.getSize() == null ? DEFAULT_PAGESIZE : pagination.getSize().longValue();
         long from = pageNum > 0 ? (pageNum - 1) * size : 0;
         output.setData(keyCredential.keySet().stream().skip(from).limit(size).map(e -> e.getKeyId())
                 .collect(Collectors.toList()));