Fix a couple sonarcloud issues with samza-1537

Author: Jacob Maes <[email protected]>

Reviewers: Jagadish <[email protected]>

Closes apache#393 from jmakes/streamappender-sonarcloud

Author: jmakes

samza-log4j/src/main/java/org/apache/samza/logging/log4j/StreamAppender.java

@@ -152,7 +152,7 @@ public void append(LoggingEvent event) {
             // Emit a metric which can be monitored to ensure it doesn't happen often.
             metrics.logMessagesDropped.inc(messagesDropped);
           }
-          metrics.bufferFillPct.set(Math.round(100 * logQueue.size() / DEFAULT_QUEUE_SIZE));
+          metrics.bufferFillPct.set(Math.round(100f * logQueue.size() / DEFAULT_QUEUE_SIZE));
         }
       } catch (Exception e) {
         System.err.println("[StreamAppender] Error sending log message:");
@@ -188,7 +188,8 @@ public void close() {
       try {
         transferThread.join();
       } catch (InterruptedException e) {
-        log.error("Interrupted while waiting for sink thread to finish.", e);
+        log.error("Interrupted while waiting for transfer thread to finish.", e);
+        Thread.currentThread().interrupt();
       }
 
       flushSystemProducer();