HBASE-27236 Clean up error-prone warnings in hbase-hbtop

hbase-hbtop/src/main/java/org/apache/hadoop/hbase/hbtop/HBTop.java

@@ -36,6 +36,7 @@
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
+import org.apache.hbase.thirdparty.com.google.common.base.Splitter;
 import org.apache.hbase.thirdparty.org.apache.commons.cli.CommandLine;
 import org.apache.hbase.thirdparty.org.apache.commons.cli.DefaultParser;
 import org.apache.hbase.thirdparty.org.apache.commons.cli.HelpFormatter;
@@ -119,6 +120,7 @@ public int run(String[] args) throws Exception {
         try {
           delay = Integer.parseInt(commandLine.getOptionValue("delay"));
         } catch (NumberFormatException ignored) {
+          // Deliberately ignored, we handle the issue below.
         }
 
         if (delay < 1) {
@@ -163,7 +165,7 @@ public int run(String[] args) throws Exception {
       }
 
       if (commandLine.hasOption("fields")) {
-        String[] fields = commandLine.getOptionValue("fields").split(",");
+        Iterable<String> fields = Splitter.on(',').split(commandLine.getOptionValue("fields"));
         initialFields = new ArrayList<>();
         for (String field : fields) {
           Optional<FieldInfo> fieldInfo = initialMode.getFieldInfos().stream()
@@ -177,7 +179,7 @@ public int run(String[] args) throws Exception {
       }
 
       if (commandLine.hasOption("filters")) {
-        String[] filters = commandLine.getOptionValue("filters").split(",");
+        Iterable<String> filters = Splitter.on(',').split(commandLine.getOptionValue("filters"));
         List<Field> fields = initialMode.getFieldInfos().stream().map(FieldInfo::getField)
           .collect(Collectors.toList());
         for (String filter : filters) {

hbase-hbtop/src/main/java/org/apache/hadoop/hbase/hbtop/mode/Mode.java

@@ -31,6 +31,7 @@
  * Represents a display mode in the top screen.
  */
 @InterfaceAudience.Private
+@SuppressWarnings("ImmutableEnumChecker")
 public enum Mode {
   NAMESPACE("Namespace", "Record per Namespace", new NamespaceModeStrategy()),
   TABLE("Table", "Record per Table", new TableModeStrategy()),

hbase-hbtop/src/main/java/org/apache/hadoop/hbase/hbtop/mode/RegionModeStrategy.java

@@ -115,6 +115,7 @@ private Record createRecord(ServerMetrics serverMetrics, RegionMetrics regionMet
         elements.length == 4 ? Integer.valueOf(Bytes.toString(elements[3])).toString() : "";
       region = RegionInfo.encodeRegionName(regionMetrics.getRegionName());
     } catch (IOException ignored) {
+      // Exception deliberately ignored
     }
 
     builder.put(Field.NAMESPACE, namespaceName);

hbase-hbtop/src/main/java/org/apache/hadoop/hbase/hbtop/terminal/TerminalPrinter.java

@@ -61,6 +61,7 @@ default TerminalPrinter print(double value) {
     return this;
   }
 
+  @SuppressWarnings("AnnotateFormatMethod")
   default TerminalPrinter printFormat(String format, Object... args) {
     print(String.format(format, args));
     return this;

hbase-hbtop/src/main/java/org/apache/hadoop/hbase/hbtop/terminal/impl/KeyPressGenerator.java

@@ -112,7 +112,10 @@ private void readerThread() {
         } else {
           Thread.sleep(20);
         }
-      } catch (InterruptedException ignored) {
+      } catch (InterruptedException e) {
+        // Restore interrupt status
+        Thread.currentThread().interrupt();
+        done = true;
       } catch (IOException e) {
         LOGGER.error("Caught an exception", e);
         done = true;

hbase-hbtop/src/main/java/org/apache/hadoop/hbase/hbtop/terminal/impl/TerminalImpl.java

@@ -213,7 +213,9 @@ private String doStty(String sttyOptionsString) {
 
       try {
         process.waitFor();
-      } catch (InterruptedException ignored) {
+      } catch (InterruptedException e) {
+        // Restore interrupt status
+        Thread.currentThread().interrupt();
       }
 
       int exitValue = process.exitValue();

hbase-hbtop/src/test/java/org/apache/hadoop/hbase/hbtop/TestUtils.java

@@ -114,6 +114,7 @@ private static UserMetrics createUserMetrics(String user, long readRequestCount,
       .build();
   }
 
+  @SuppressWarnings("JavaUtilDate")
   private static RegionMetrics createRegionMetrics(String regionName, long readRequestCount,
     long filteredReadRequestCount, long writeRequestCount, Size storeFileSize,
     Size uncompressedStoreFileSize, int storeFileCount, Size memStoreSize, float locality,