[PR #1] Refactoring Thread > Executor

src/main/java/com/datadoghq/trace/writer/impl/DDAgentWriter.java

@@ -7,13 +7,11 @@ import org.slf4j.LoggerFactory;
 
 import java.util.ArrayList;
 import java.util.List;
-import java.util.concurrent.ArrayBlockingQueue;
-import java.util.concurrent.BlockingQueue;
-import java.util.concurrent.Semaphore;
+import java.util.concurrent.*;
 
 /**
  * This writer write provided traces to the a DD agent which is most of time located on the same host.
- * 
+ * <p>
  * It handles writes asynchronuously so the calling threads are automatically released. However, if too much spans are collected
  * the writers can reach a state where it is forced to drop incoming spans.
  */
@@ -50,7 +48,7 @@ public class DDAgentWriter implements Writer {
     /**
      * Async worker that posts the spans to the DD agent
      */
-	private final Thread asyncWriterThread;
+    private final ExecutorService executor = Executors.newSingleThreadExecutor();
 
     /**
      * The DD agent api
@@ -68,9 +66,8 @@ public class DDAgentWriter implements Writer {
         tokens = new Semaphore(DEFAULT_MAX_SPANS);
         traces = new ArrayBlockingQueue<List<Span>>(DEFAULT_MAX_SPANS);
 
-		asyncWriterThread = new Thread(new SpansSendingTask(), "dd.DDAgentWriter-SpansSendingTask");
-		asyncWriterThread.setDaemon(true);
-		asyncWriterThread.start();
+        executor.submit(new SpansSendingTask());
+
     }
 
     /* (non-Javadoc)
@@ -80,9 +77,9 @@ public class DDAgentWriter implements Writer {
         //Try to add a new span in the queue
         boolean proceed = tokens.tryAcquire(trace.size());
 
-		if(proceed){
+        if (proceed) {
             traces.add(trace);
-		}else{
+        } else {
             logger.warn("Cannot add a trace of {} as the async queue is full. Queue max size: {}", trace.size(), DEFAULT_MAX_SPANS);
         }
     }
@@ -91,9 +88,9 @@ public class DDAgentWriter implements Writer {
      * @see com.datadoghq.trace.Writer#close()
      */
     public void close() {
-		asyncWriterThread.interrupt();
+        executor.shutdownNow();
         try {
-			asyncWriterThread.join();
+            executor.awaitTermination(500, TimeUnit.MILLISECONDS);
         } catch (InterruptedException e) {
             logger.info("Writer properly closed and async writer interrupted.");
         }
@@ -122,8 +119,8 @@ public class DDAgentWriter implements Writer {
 
                     //Compute the number of spans sent
                     int spansCount = 0;
-					for(List<Span> trace:payload){
-						spansCount+=trace.size();
+                    for (List<Span> trace : payload) {
+                        spansCount += trace.size();
                     }
                     logger.debug("Async writer just sent {} spans through {} traces", spansCount, payload.size());