changes

src/main/java/home/automation/RegistryMapping.java

@@ -1,7 +1,20 @@
 package home.automation;
 
-public class RegistryMapping{
-    public int registry;
-    public String desc;
+public class RegistryMapping {
+    private final int registry;
+    private final String desc;
+
+    public RegistryMapping(int registry, String desc) {
+        this.registry = registry;
+        this.desc = desc;
+    }
+
+    public int getRegistry() {
+        return registry;
+    }
+
+    public String getDesc() {
+        return desc;
+    }
 }
 

src/main/java/home/automation/SDMService.java

@@ -1,22 +1,36 @@
 package home.automation;
 
+import com.ghgande.j2mod.modbus.ModbusException;
 import com.ghgande.j2mod.modbus.facade.ModbusTCPMaster;
+import com.ghgande.j2mod.modbus.procimg.Register;
 
 import java.net.InetAddress;
 
 public class SDMService {
 
     private final InetAddress address;
+    private final ModbusTCPMaster modbusConnection;
     private final int port;
 
-    public SDMService(InetAddress address, int port) {
+    public SDMService(InetAddress address, int port) throws Exception {
         this.address = address;
         this.port = port;
+        this.modbusConnection = initConnection();
     }
 
-    private void initConnection() throws Exception {
+    public Register[] read(RegistryMapping mapping) {
+        try {
+            return modbusConnection.readMultipleRegisters(mapping.getRegistry(), 1);
+        } catch (ModbusException e) {
+            e.printStackTrace();
+        }
+        return new Register[0];
+    }
+
+    private ModbusTCPMaster initConnection() throws Exception {
         ModbusTCPMaster modbusRTUTCPTransport = new ModbusTCPMaster(address.getHostAddress(), port);
         modbusRTUTCPTransport.connect();
+        return modbusRTUTCPTransport;
     }
 
 }