Log ExecutorServiceMetrics.bindTo() failure (#2443)

* Log ExecutorServiceMetrics.bindTo() failure

See gh-2426

* Fix a wrong class reference for a logger

Co-authored-by: Jonatan Ivanov <jonatan.ivanov@gmail.com>

* Use conventional order for modifiers

Co-authored-by: Jonatan Ivanov <jonatan.ivanov@gmail.com>

Co-authored-by: Jonatan Ivanov <jonatan.ivanov@gmail.com>

micrometer-core/src/main/java/io/micrometer/core/instrument/binder/jvm/ExecutorServiceMetrics.java

@@ -25,6 +25,8 @@
 import io.micrometer.core.lang.NonNullApi;
 import io.micrometer.core.lang.NonNullFields;
 import io.micrometer.core.lang.Nullable;
+import io.micrometer.core.util.internal.logging.InternalLogger;
+import io.micrometer.core.util.internal.logging.InternalLoggerFactory;
 
 import java.lang.reflect.Field;
 import java.util.concurrent.*;
@@ -43,6 +45,9 @@
 @NonNullApi
 @NonNullFields
 public class ExecutorServiceMetrics implements MeterBinder {
+
+    private static final InternalLogger log = InternalLoggerFactory.getInstance(ExecutorServiceMetrics.class);
+
     static final String DEFAULT_EXECUTOR_METRIC_PREFIX = "";
     @Nullable
     private final ExecutorService executorService;
@@ -277,6 +282,8 @@ public void bindTo(MeterRegistry registry) {
             monitor(registry, unwrapThreadPoolExecutor(executorService, executorService.getClass().getSuperclass()));
         } else if (executorService instanceof ForkJoinPool) {
             monitor(registry, (ForkJoinPool) executorService);
+        } else {
+            log.warn("Failed to bind as {} is unsupported.", className);
         }
     }