Changed check for blank string and added minor improvements

application/src/test/java/org/thingsboard/server/controller/DeviceConnectivityControllerTest.java

@@ -724,7 +724,7 @@ public class DeviceConnectivityControllerTest extends AbstractControllerTest {
     }
 
     @Test
-    public void testFetchPublishTelemetryCommandsForHostSetToNullInSettings() throws Exception {
+    public void testFetchPublishTelemetryCommandsForDeviceWhenHostSetToNullInSettings() throws Exception {
         loginSysAdmin();
         ObjectNode config = JacksonUtil.newObjectNode();
 
@@ -742,26 +742,26 @@ public class DeviceConnectivityControllerTest extends AbstractControllerTest {
 
         ObjectNode mqtt = JacksonUtil.newObjectNode();
         mqtt.put("enabled", true);
-        mqtt.put("host", NullNode.getInstance());
-        mqtt.put("port", NullNode.getInstance());
+        mqtt.set("host", NullNode.getInstance());
+        mqtt.set("port", NullNode.getInstance());
         config.set("mqtt", mqtt);
 
         ObjectNode mqtts = JacksonUtil.newObjectNode();
         mqtts.put("enabled", true);
         mqtts.put("host", "");
-        mqtts.put("port", NullNode.getInstance());
+        mqtts.set("port", NullNode.getInstance());
         config.set("mqtts", mqtts);
 
         ObjectNode coap = JacksonUtil.newObjectNode();
         coap.put("enabled", true);
-        coap.put("host", NullNode.getInstance());
+        coap.set("host", NullNode.getInstance());
         coap.put("port", "");
         config.set("coap", coap);
 
         ObjectNode coaps = JacksonUtil.newObjectNode();
         coaps.put("enabled", true);
-        coaps.put("host", NullNode.getInstance());
-        coaps.put("port", NullNode.getInstance());
+        coaps.set("host", NullNode.getInstance());
+        coaps.set("port", NullNode.getInstance());
         config.set("coaps", coaps);
 
         AdminSettings adminSettings = doGet("/api/admin/settings/connectivity", AdminSettings.class);

dao/src/main/java/org/thingsboard/server/dao/device/DeviceConnectivityServiceImpl.java

@@ -328,14 +328,14 @@ public class DeviceConnectivityServiceImpl implements DeviceConnectivityService
     private String getCoapPublishCommand(String protocol, String baseUrl, DeviceCredentials deviceCredentials) throws URISyntaxException {
         DeviceConnectivityInfo properties = getConnectivity(protocol);
         String hostName = getHost(baseUrl, properties, protocol);
-        String port = properties.getPort() == null || properties.getPort().isEmpty() ? "" : ":" + properties.getPort();
+        String port = StringUtils.isBlank(properties.getPort()) ? "" : ":" + properties.getPort();
         return DeviceConnectivityUtil.getCoapPublishCommand(protocol, hostName, port, deviceCredentials);
     }
 
     private String getDockerCoapPublishCommand(String protocol, String baseUrl, DeviceCredentials deviceCredentials) throws URISyntaxException {
         DeviceConnectivityInfo properties = getConnectivity(protocol);
         String host = getHost(baseUrl, properties, protocol);
-        String port = properties.getPort() == null || properties.getPort().isEmpty() ? "" : ":" + properties.getPort();
+        String port = StringUtils.isBlank(properties.getPort()) ? "" : ":" + properties.getPort();
         return DeviceConnectivityUtil.getDockerCoapPublishCommand(protocol, host, port, deviceCredentials);
     }
 

dao/src/main/java/org/thingsboard/server/dao/util/DeviceConnectivityUtil.java

@@ -18,6 +18,7 @@ package org.thingsboard.server.dao.util;
 import org.springframework.core.io.ByteArrayResource;
 import org.springframework.core.io.Resource;
 import org.thingsboard.common.util.JacksonUtil;
+import org.thingsboard.server.common.data.StringUtils;
 import org.thingsboard.server.common.data.device.credentials.BasicMqttCredentials;
 import org.thingsboard.server.common.data.security.DeviceCredentials;
 import org.thingsboard.server.dao.device.DeviceConnectivityInfo;
@@ -63,7 +64,7 @@ public class DeviceConnectivityUtil {
         if (MQTTS.equals(protocol)) {
             command.append(" --cafile ").append(CA_ROOT_CERT_PEM);
         }
-        command.append(" -h ").append(host).append(port.isBlank() ? "" : " -p " + port);
+        command.append(" -h ").append(host).append(StringUtils.isBlank(port) ? "" : " -p " + port);
         command.append(" -t ").append(deviceTelemetryTopic);
 
         switch (deviceCredentials.getCredentialsType()) {
@@ -219,7 +220,7 @@ public class DeviceConnectivityUtil {
     }
 
     public static String getHost(String baseUrl, DeviceConnectivityInfo properties, String protocol) throws URISyntaxException {
-        String initialHost = properties.getHost() == null || properties.getHost().isBlank() ? baseUrl : properties.getHost();
+        String initialHost = StringUtils.isBlank(properties.getHost()) ? baseUrl : properties.getHost();
         InetAddress inetAddress;
         String host = null;
         if (VALID_URL_PATTERN.matcher(initialHost).matches()) {
@@ -244,7 +245,7 @@ public class DeviceConnectivityUtil {
     }
 
     public static String getPort(DeviceConnectivityInfo properties) {
-        return properties.getPort() == null || properties.getPort().isBlank() ? "" : properties.getPort();
+        return StringUtils.isBlank(properties.getPort()) ? "" : properties.getPort();
     }
 
     public static boolean isLocalhost(String host) {