add checkstyle

Signed-off-by: Gregor Zeitlinger <[email protected]>

Author: zeitlinger

prometheus-metrics-instrumentation-dropwizard5/src/main/java/io/prometheus/metrics/instrumentation/dropwizard5/DropwizardExports.java

@@ -30,7 +30,7 @@
 
 /** Collect Dropwizard metrics from a MetricRegistry. */
 public class DropwizardExports implements MultiCollector {
-  private static final Logger LOGGER = Logger.getLogger(DropwizardExports.class.getName());
+  private static final Logger logger = Logger.getLogger(DropwizardExports.class.getName());
   private final MetricRegistry registry;
   private final MetricFilter metricFilter;
   private final Optional<CustomLabelMapper> labelMapper;
@@ -109,7 +109,7 @@ MetricSnapshot fromGauge(String dropwizardName, Gauge<?> gauge) {
     } else if (obj instanceof Boolean) {
       value = ((Boolean) obj) ? 1 : 0;
     } else {
-      LOGGER.log(
+      logger.log(
           Level.FINE,
           String.format(
               "Invalid type for Gauge %s: %s",

prometheus-metrics-instrumentation-dropwizard5/src/main/java/io/prometheus/metrics/instrumentation/dropwizard5/labels/MapperConfig.java

@@ -127,13 +127,21 @@ private void validateLabels(final Map<String, String> labels) {
 
   @Override
   public boolean equals(final Object o) {
-    if (this == o) return true;
-    if (o == null || getClass() != o.getClass()) return false;
+    if (this == o) {
+      return true;
+    }
+    if (o == null || getClass() != o.getClass()) {
+      return false;
+    }
 
     final MapperConfig that = (MapperConfig) o;
 
-    if (match != null ? !match.equals(that.match) : that.match != null) return false;
-    if (name != null ? !name.equals(that.name) : that.name != null) return false;
+    if (match != null ? !match.equals(that.match) : that.match != null) {
+      return false;
+    }
+    if (name != null ? !name.equals(that.name) : that.name != null) {
+      return false;
+    }
     return labels != null ? labels.equals(that.labels) : that.labels == null;
   }