Add failure analyzer for incorrect interface name

src/main/java/ru/serega6531/packmate/exception/PcapInterfaceNotFoundException.java

@@ -0,0 +1,15 @@
+package ru.serega6531.packmate.exception;
+
+import lombok.Data;
+import lombok.EqualsAndHashCode;
+
+import java.util.List;
+
+@EqualsAndHashCode(callSuper = true)
+@Data
+public class PcapInterfaceNotFoundException extends RuntimeException {
+
+    private final String requestedInterface;
+    private final List<String> existingInterfaces;
+
+}

src/main/java/ru/serega6531/packmate/exception/analyzer/PcapFileNotFoundFailureAnalyzer.java

@@ -14,7 +14,6 @@ public class PcapFileNotFoundFailureAnalyzer extends AbstractFailureAnalyzer<Pca
         String description = "The file " + cause.getFile().getAbsolutePath() + " was not found";
         String existingFilesMessage;
 
-
         File[] existingFiles = cause.getDirectory().listFiles();
 
         if (existingFiles == null) {
@@ -26,7 +25,6 @@ public class PcapFileNotFoundFailureAnalyzer extends AbstractFailureAnalyzer<Pca
             );
         }
 
-
         if (existingFiles.length == 0) {
             existingFilesMessage = "The pcaps directory is currently empty";
         } else {

src/main/java/ru/serega6531/packmate/exception/analyzer/PcapInterfaceNotFoundFailureAnalyzer.java

@@ -0,0 +1,16 @@
+package ru.serega6531.packmate.exception.analyzer;
+
+import org.springframework.boot.diagnostics.AbstractFailureAnalyzer;
+import org.springframework.boot.diagnostics.FailureAnalysis;
+import ru.serega6531.packmate.exception.PcapInterfaceNotFoundException;
+
+public class PcapInterfaceNotFoundFailureAnalyzer extends AbstractFailureAnalyzer<PcapInterfaceNotFoundException> {
+    @Override
+    protected FailureAnalysis analyze(Throwable rootFailure, PcapInterfaceNotFoundException cause) {
+        return new FailureAnalysis(
+                "The interface \"" + cause.getRequestedInterface() + "\" was not found",
+                "Check the interface name in the config. Existing interfaces are: " + cause.getExistingInterfaces(),
+                cause
+        );
+    }
+}

src/main/java/ru/serega6531/packmate/pcap/LivePcapWorker.java

@@ -6,10 +6,12 @@ import org.apache.commons.lang3.concurrent.BasicThreadFactory;
 import org.pcap4j.core.PcapNativeException;
 import org.pcap4j.core.PcapNetworkInterface;
 import org.pcap4j.core.Pcaps;
+import ru.serega6531.packmate.exception.PcapInterfaceNotFoundException;
 import ru.serega6531.packmate.service.ServicesService;
 import ru.serega6531.packmate.service.StreamService;
 
 import java.net.UnknownHostException;
+import java.util.List;
 import java.util.concurrent.LinkedBlockingQueue;
 import java.util.concurrent.ThreadPoolExecutor;
 import java.util.concurrent.TimeUnit;
@@ -26,9 +28,9 @@ public class LivePcapWorker extends AbstractPcapWorker {
         super(servicesService, streamService, localIpString);
         device = Pcaps.getDevByName(interfaceName);
 
-        if(device == null) {
+        if (device == null) {
-            log.info("Existing devices: {}", Pcaps.findAllDevs().stream().map(PcapNetworkInterface::getName).toList());
+            List<String> existingInterfaces = Pcaps.findAllDevs().stream().map(PcapNetworkInterface::getName).toList();
-            throw new IllegalArgumentException("Device " + interfaceName + " does not exist");
+            throw new PcapInterfaceNotFoundException(interfaceName, existingInterfaces);
         }
 
         BasicThreadFactory factory = new BasicThreadFactory.Builder()

src/main/resources/META-INF/spring.factories

@@ -1,2 +1,3 @@
 org.springframework.boot.diagnostics.FailureAnalyzer=\
-  ru.serega6531.packmate.exception.analyzer.PcapFileNotFoundFailureAnalyzer
+  ru.serega6531.packmate.exception.analyzer.PcapFileNotFoundFailureAnalyzer,\
+  ru.serega6531.packmate.exception.analyzer.PcapInterfaceNotFoundFailureAnalyzer