fix checkpoint dir

@@ -35,7 +35,7 @@ public class ExecutorBuilder {
     private Function0<SparkConf> sparkConf;
     private Function0<JavaStreamingContext> streamingContext;
     private Map<String, String> kafkaParamMap = new HashMap<>();
-    private String checkpointDir = "/spark/checkpoint/trace";
+    private String checkpointDir = "/spark/checkpoint/" + APP_NAME;
 
 
     public ExecutorBuilder sparkConf() {
@@ -90,7 +90,7 @@ public class ExecutorBuilder {
                 List<Spans> messages = new ArrayList<>();
                 ObjectMapper jacksonMapper = new ObjectMapper();
 
-                long current = System.currentTimeMillis() ;
+                long current = System.currentTimeMillis();
 
                 while (msgIterator.hasNext()) {
                     Tuple2<byte[], byte[]> msgTuple2 = msgIterator.next();