Extract control event parsing to separate methods

Use one parse method per control event type.

server/src/main/java/com/genymobile/scrcpy/ControlEventReader.java

@@ -47,61 +47,86 @@ public class ControlEventReader {
         int savedPosition = buffer.position();
 
         int type = buffer.get();
+        ControlEvent controlEvent;
         switch (type) {
-            case ControlEvent.TYPE_KEYCODE: {
+            case ControlEvent.TYPE_KEYCODE:
-                if (buffer.remaining() < KEYCODE_PAYLOAD_LENGTH) {
+                controlEvent = parseKeycodeControlEvent();
                 break;
+            case ControlEvent.TYPE_TEXT:
+                controlEvent = parseTextControlEvent();
+                break;
+            case ControlEvent.TYPE_MOUSE:
+                controlEvent = parseMouseControlEvent();
+                break;
+            case ControlEvent.TYPE_SCROLL:
+                controlEvent = parseScrollControlEvent();
+                break;
+            case ControlEvent.TYPE_COMMAND:
+                controlEvent = parseCommandControlEvent();
+                break;
+            default:
+                Ln.w("Unknown event type: " + type);
+                controlEvent = null;
+                break;
+        }
+
+        if (controlEvent == null) {
+            // failure, reset savedPosition
+            buffer.position(savedPosition);
+        }
+        return controlEvent;
+    }
+
+    private ControlEvent parseKeycodeControlEvent() {
+        if (buffer.remaining() < KEYCODE_PAYLOAD_LENGTH) {
+            return null;
         }
         int action = toUnsigned(buffer.get());
         int keycode = buffer.getInt();
         int metaState = buffer.getInt();
         return ControlEvent.createKeycodeControlEvent(action, keycode, metaState);
     }
-            case ControlEvent.TYPE_TEXT: {
+
+    private ControlEvent parseTextControlEvent() {
         if (buffer.remaining() < 1) {
-                    break;
+            return null;
         }
         int len = toUnsigned(buffer.get());
         if (buffer.remaining() < len) {
-                    break;
+            return null;
         }
         buffer.get(textBuffer, 0, len);
         String text = new String(textBuffer, 0, len, StandardCharsets.UTF_8);
         return ControlEvent.createTextControlEvent(text);
     }
-            case ControlEvent.TYPE_MOUSE: {
+
+    private ControlEvent parseMouseControlEvent() {
         if (buffer.remaining() < MOUSE_PAYLOAD_LENGTH) {
-                    break;
+            return null;
         }
         int action = toUnsigned(buffer.get());
         int buttons = buffer.getInt();
         Position position = readPosition(buffer);
         return ControlEvent.createMotionControlEvent(action, buttons, position);
     }
-            case ControlEvent.TYPE_SCROLL: {
+
+    private ControlEvent parseScrollControlEvent() {
         if (buffer.remaining() < SCROLL_PAYLOAD_LENGTH) {
-                    break;
+            return null;
         }
         Position position = readPosition(buffer);
         int hScroll = buffer.getInt();
         int vScroll = buffer.getInt();
         return ControlEvent.createScrollControlEvent(position, hScroll, vScroll);
     }
-            case ControlEvent.TYPE_COMMAND: {
+
+    private ControlEvent parseCommandControlEvent() {
         if (buffer.remaining() < COMMAND_PAYLOAD_LENGTH) {
-                    break;
+            return null;
         }
         int action = toUnsigned(buffer.get());
         return ControlEvent.createCommandControlEvent(action);
     }
-            default:
-                Ln.w("Unknown event type: " + type);
-        }
-
-        // failure, reset savedPosition
-        buffer.position(savedPosition);
-        return null;
-    }
 
     private static Position readPosition(ByteBuffer buffer) {
         int x = toUnsigned(buffer.getShort());