Refactored checkPort method. Seperated error handling code from business

logic

1 files changed, 31 insertions, 26 deletions

diff --git a/src/main/java/com/it_jaros/jns/scan/engine/ScanPortTask.java b/src/main/java/com/it_jaros/jns/scan/engine/ScanPortTask.java
index 2203db6..1e709d5 100644
--- a/src/main/java/com/it_jaros/jns/scan/engine/ScanPortTask.java
+++ b/src/main/java/com/it_jaros/jns/scan/engine/ScanPortTask.java
@@ -61,31 +61,10 @@ public class ScanPortTask implements Callable<PortResult> {
         result.setPort(port);
         result.setState(PortState.UNKNOWN);
         try(SocketChannel socketChannel = SocketChannel.open()) {
-            socketChannel.configureBlocking(false);
-            socketChannel.connect(new InetSocketAddress(inetAddress, port));
-            final long deadlineNanos = System.nanoTime() + timeoutInNanos;
-            final long waitInNanos = TimeUnit.MILLISECONDS.toNanos(1000);
-            boolean isConnected = socketChannel.finishConnect();
-            while (!cancelledToken.isCancelled() && !isConnected) {
-                long remainingNanos = deadlineNanos - System.nanoTime();
-                if (remainingNanos <= 0) {
-                    break;
-                }
-                LockSupport.parkNanos(Math.min(waitInNanos, remainingNanos));
-                isConnected = socketChannel.finishConnect();
-            }
-
-            if (cancelledToken.isCancelled()) {
-                return result;
-            }
-
-            if (isConnected) {
-                result.setState(PortState.OPEN);
-                if (bannerRecognition) {
-                    result.setBanner(getBanner(socketChannel));
-                }
-            } else {
-                result.setState(PortState.FILTERED);
+            PortState state = getPortState(socketChannel);
+            result.setState(state);
+            if (PortState.OPEN.equals(state) && bannerRecognition) {
+                result.setBanner(getBanner(socketChannel));
             }
         } catch (ConnectException ignored) {
             result.setState(PortState.CLOSED);
@@ -96,6 +75,32 @@ public class ScanPortTask implements Callable<PortResult> {
         return result;
     }
 
+    private PortState getPortState(SocketChannel socketChannel) throws IOException {
+        socketChannel.configureBlocking(false);
+        socketChannel.connect(new InetSocketAddress(inetAddress, port));
+        final long deadlineNanos = System.nanoTime() + timeoutInNanos;
+        final long waitInNanos = TimeUnit.MILLISECONDS.toNanos(1000);
+        boolean isConnected = socketChannel.finishConnect();
+        while (!cancelledToken.isCancelled() && !isConnected) {
+            long remainingNanos = deadlineNanos - System.nanoTime();
+            if (remainingNanos <= 0) {
+                break;
+            }
+            LockSupport.parkNanos(Math.min(waitInNanos, remainingNanos));
+            isConnected = socketChannel.finishConnect();
+        }
+
+        if (isConnected) {
+            return PortState.OPEN;
+        }
+
+        if (cancelledToken.isCancelled()) {
+            return PortState.UNKNOWN;
+        }
+
+        return PortState.FILTERED;
+    }
+
     private byte[] getBanner(SocketChannel socketChannel) {
         try {
             return tryReadFrom(socketChannel);
@@ -103,7 +108,7 @@ public class ScanPortTask implements Callable<PortResult> {
             // ignore
         }
 
-        return null;
+        return new byte[0];
     }
 
     private byte[] tryReadFrom(SocketChannel socketChannel) throws IOException {