Clean Code

2 files changed, 18 insertions, 16 deletions

diff --git a/src/main/java/com/it_jaros/jscanner/App.java b/src/main/java/com/it_jaros/jscanner/App.java
index 615262a..573e46f 100644
--- a/src/main/java/com/it_jaros/jscanner/App.java
+++ b/src/main/java/com/it_jaros/jscanner/App.java
@@ -1,5 +1,6 @@
 package com.it_jaros.jscanner;
 
+import java.io.IOException;
 import java.util.concurrent.CountDownLatch;
 
 public class App {
@@ -12,36 +13,37 @@ public class App {
             run(args);
         } catch (Exception e) {
             System.out.printf("%nFATAL ERROR: %s", e.getMessage());
+        } finally {
+            shutdownLatch.countDown();
+            removeShutdownHook();
         }
     }
 
     private static void run(String[] args) throws Exception {
         ScanOptions options = parseOptions(args);
-        if (options == null) return;
         try (Scanner scanner = new Scanner(options)) {
-            addShutdownHook(scanner);
-            Scan scan = Scan.create(options);
-            ProgressBar progressBar = new ProgressBar(scan, options.quiet());
-            progressBar.start();
-            scanner.runScan(scan, result -> progressBar.printResult(result, options.showFilteredPorts()));
-            progressBar.stop();
-        } finally {
-            shutdownLatch.countDown();
-            removeShutdownHook();
+            runScan(scanner, options);
         }
     }
 
+    private static void runScan(Scanner scanner, ScanOptions options) throws IOException {
+        addShutdownHook(scanner);
+        Scan scan = Scan.create(options);
+        ProgressBar progressBar = new ProgressBar(scan, options.quiet());
+        progressBar.start();
+        scanner.runScan(scan, result -> progressBar.printResult(result, options.showFilteredPorts()));
+        progressBar.stop();
+    }
+
     private static ScanOptions parseOptions(String[] args) {
         CliParser cliParser = new CliParser();
         try {
             return cliParser.parseArgs(args);
         } catch (IllegalArgumentException e) {
-            System.out.printf("Error while parsing arguments: %s", e.getMessage());
-            System.out.println();
+            System.out.printf("Error while parsing arguments: %s%n", e.getMessage());
+            cliParser.usageAndExit(1);
+            throw e;
         }
-
-        cliParser.usageAndExit(1);
-        return null;
     }
 
     /**
diff --git a/src/main/java/com/it_jaros/jscanner/CliParser.java b/src/main/java/com/it_jaros/jscanner/CliParser.java
index 707abb5..81ee88d 100644
--- a/src/main/java/com/it_jaros/jscanner/CliParser.java
+++ b/src/main/java/com/it_jaros/jscanner/CliParser.java
@@ -73,7 +73,7 @@ public class CliParser {
         }
 
         if (hostsArgv.isEmpty() && hostsFile == null) {
-           throw new IllegalStateException("No input provided. Check with --help for available options.");
+           throw new IllegalArgumentException("No input provided. Check with --help for available options.");
         }
 
         return new ScanOptions(hostsArgv.stream().toList(), socketLimit, delayInMillis, timeoutInMillis, maxWorkersPerHost, maxHostsLimit, ports, showFilteredPorts, disableOnlineCheck, hostsFile, quiet, bannerRecognition);