Minor fixes.

jaeger-core/src/test/java/io/jaegertracing/JaegerSpanTest.java

@@ -328,11 +328,7 @@ public void testLogAfterFinish() {
 
   @Test
   public void testLogWithTimestampAfterFinish() {
-    Map<String, String> unexpectedFields = new HashMap<String, String>() {
-      {
-        put("foo", "bar");
-      }
-    };
+    Map<String, String> unexpectedFields = Collections.singletonMap("foo", "bar");
 
     jaegerSpan.finish();
     jaegerSpan.log(2222, unexpectedFields);
@@ -496,7 +492,7 @@ public void testNoExpandExceptionLogs() {
         .withSampler(new ConstSampler(true))
         .build();
 
-    JaegerSpan jaegerSpan = (JaegerSpan)tracer.buildSpan("foo").start();
+    JaegerSpan jaegerSpan = tracer.buildSpan("foo").start();
 
     RuntimeException ex = new RuntimeException();
     Map<String, Object> logs = new HashMap<>();
@@ -512,7 +508,7 @@ public void testNoExpandExceptionLogs() {
   @Test
   public void testNoLoggingingStackTracesOnDebug() {
     log.setEnabledLevels(Level.WARN);
-    JaegerSpan jaegerSpan = (JaegerSpan)tracer.buildSpan("foo").start();
+    JaegerSpan jaegerSpan = tracer.buildSpan("foo").start();
     jaegerSpan.finish();
     jaegerSpan.finish();
 
@@ -526,7 +522,7 @@ public void testNoLoggingingStackTracesOnDebug() {
   @Test
   public void testLoggingingStackTracesOnDebug() {
     log.setEnabledLevels(Level.WARN, Level.DEBUG);
-    JaegerSpan jaegerSpan = (JaegerSpan)tracer.buildSpan("foo").start();
+    JaegerSpan jaegerSpan = tracer.buildSpan("foo").start();
     jaegerSpan.finish();
     jaegerSpan.finish();