HBASE-26819 Minor code cleanup in and around RpcScheduler

Signed-off-by: Duo Zhang <zhangduo@apache.org>

hbase-server/src/main/java/org/apache/hadoop/hbase/ipc/FifoRpcScheduler.java

@@ -1,4 +1,4 @@
-/**
+/*
  * Licensed to the Apache Software Foundation (ASF) under one
  * or more contributor license agreements.  See the NOTICE file
  * distributed with this work for additional information
@@ -17,7 +17,6 @@
  */
 package org.apache.hadoop.hbase.ipc;
 
-import java.io.IOException;
 import java.util.HashMap;
 import java.util.concurrent.ArrayBlockingQueue;
 import java.util.concurrent.BlockingQueue;
@@ -26,11 +25,10 @@ import java.util.concurrent.TimeUnit;
 import java.util.concurrent.atomic.AtomicInteger;
 import org.apache.hadoop.conf.Configuration;
 import org.apache.hadoop.hbase.util.Threads;
-import org.apache.hbase.thirdparty.com.google.common.util.concurrent.ThreadFactoryBuilder;
 import org.apache.yetus.audience.InterfaceAudience;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
-
+import org.apache.hbase.thirdparty.com.google.common.util.concurrent.ThreadFactoryBuilder;
 import org.apache.hbase.thirdparty.io.netty.util.internal.StringUtil;
 
 /**
@@ -92,7 +90,7 @@ public class FifoRpcScheduler extends RpcScheduler {
   }
 
   @Override
-  public boolean dispatch(final CallRunner task) throws IOException, InterruptedException {
+  public boolean dispatch(final CallRunner task) {
     return executeRpcCall(executor, queueSize, task);
   }
 

hbase-server/src/main/java/org/apache/hadoop/hbase/ipc/MasterFifoRpcScheduler.java

@@ -1,4 +1,4 @@
-/**
+/*
  * Licensed to the Apache Software Foundation (ASF) under one
  * or more contributor license agreements.  See the NOTICE file
  * distributed with this work for additional information
@@ -17,20 +17,18 @@
  */
 package org.apache.hadoop.hbase.ipc;
 
-import java.io.IOException;
 import java.util.HashMap;
 import java.util.concurrent.ArrayBlockingQueue;
 import java.util.concurrent.ThreadPoolExecutor;
 import java.util.concurrent.TimeUnit;
 import java.util.concurrent.atomic.AtomicInteger;
-
 import org.apache.hadoop.conf.Configuration;
 import org.apache.hadoop.hbase.util.Threads;
-import org.apache.hbase.thirdparty.com.google.common.util.concurrent.ThreadFactoryBuilder;
 import org.apache.yetus.audience.InterfaceAudience;
 import org.apache.yetus.audience.InterfaceStability;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
+import org.apache.hbase.thirdparty.com.google.common.util.concurrent.ThreadFactoryBuilder;
 
 /**
  * A special {@code }RpcScheduler} only used for master. This scheduler separates RegionServerReport
@@ -90,7 +88,7 @@ public class MasterFifoRpcScheduler extends FifoRpcScheduler {
   }
 
   @Override
-  public boolean dispatch(final CallRunner task) throws IOException, InterruptedException {
+  public boolean dispatch(final CallRunner task) {
     String method = getCallMethod(task);
     if (rsReportExecutor != null && method != null && method.equals(REGION_SERVER_REPORT)) {
       return executeRpcCall(rsReportExecutor, rsReportQueueSize, task);

hbase-server/src/main/java/org/apache/hadoop/hbase/ipc/RpcScheduler.java

@@ -1,4 +1,4 @@
-/**
+/*
  * Licensed to the Apache Software Foundation (ASF) under one
  * or more contributor license agreements.  See the NOTICE file
  * distributed with this work for additional information
@@ -17,12 +17,10 @@
  */
 package org.apache.hadoop.hbase.ipc;
 
+import java.net.InetSocketAddress;
+import org.apache.hadoop.hbase.HBaseInterfaceAudience;
 import org.apache.yetus.audience.InterfaceAudience;
 import org.apache.yetus.audience.InterfaceStability;
-import org.apache.hadoop.hbase.HBaseInterfaceAudience;
-
-import java.io.IOException;
-import java.net.InetSocketAddress;
 
 /**
  * An interface for RPC request scheduling algorithm.
@@ -65,7 +63,7 @@ public abstract class RpcScheduler {
    *
    * @param task the request to be dispatched
    */
-  public abstract boolean dispatch(CallRunner task) throws IOException, InterruptedException;
+  public abstract boolean dispatch(CallRunner task);
 
   /** Get call queue information **/
   public abstract CallQueueInfo getCallQueueInfo();

hbase-server/src/main/java/org/apache/hadoop/hbase/ipc/SimpleRpcScheduler.java

@@ -1,4 +1,4 @@
-/**
+/*
  * Licensed to the Apache Software Foundation (ASF) under one
  * or more contributor license agreements.  See the NOTICE file
  * distributed with this work for additional information
@@ -21,10 +21,10 @@ import org.apache.hadoop.conf.Configuration;
 import org.apache.hadoop.hbase.Abortable;
 import org.apache.hadoop.hbase.HBaseInterfaceAudience;
 import org.apache.hadoop.hbase.HConstants;
-import org.apache.yetus.audience.InterfaceAudience;
-import org.apache.yetus.audience.InterfaceStability;
 import org.apache.hadoop.hbase.conf.ConfigurationObserver;
 import org.apache.hadoop.hbase.master.MasterAnnotationReadingPriorityFunction;
+import org.apache.yetus.audience.InterfaceAudience;
+import org.apache.yetus.audience.InterfaceStability;
 
 /**
  * The default scheduler. Configurable. Maintains isolated handler pools for general ('default'),
@@ -198,7 +198,7 @@ public class SimpleRpcScheduler extends RpcScheduler implements ConfigurationObs
   }
 
   @Override
-  public boolean dispatch(CallRunner callTask) throws InterruptedException {
+  public boolean dispatch(CallRunner callTask) {
     RpcCall call = callTask.getRpcCall();
     int level = priority.getPriority(call.getHeader(), call.getParam(),
         call.getRequestUser().orElse(null));

hbase-server/src/test/java/org/apache/hadoop/hbase/TestMetaTableAccessor.java

@@ -27,13 +27,11 @@ import static org.mockito.Mockito.mock;
 import static org.mockito.Mockito.reset;
 import static org.mockito.Mockito.times;
 import static org.mockito.Mockito.verify;
-
 import java.io.IOException;
 import java.util.Collections;
 import java.util.List;
 import java.util.Random;
 import java.util.concurrent.ThreadLocalRandom;
-
 import org.apache.hadoop.conf.Configuration;
 import org.apache.hadoop.hbase.client.Connection;
 import org.apache.hadoop.hbase.client.ConnectionFactory;
@@ -65,7 +63,6 @@ import org.junit.experimental.categories.Category;
 import org.junit.rules.TestName;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
-
 import org.apache.hbase.thirdparty.com.google.common.collect.Lists;
 
 /**
@@ -488,7 +485,7 @@ public class TestMetaTableAccessor {
     }
 
     @Override
-    public boolean dispatch(CallRunner task) throws IOException, InterruptedException {
+    public boolean dispatch(CallRunner task) {
       int priority = task.getRpcCall().getPriority();
 
       if (priority > HConstants.QOS_THRESHOLD) {

hbase-server/src/test/java/org/apache/hadoop/hbase/client/TestAsyncClientPauseForCallQueueTooBig.java

@@ -1,4 +1,4 @@
-/**
+/*
  * Licensed to the Apache Software Foundation (ASF) under one
  * or more contributor license agreements.  See the NOTICE file
  * distributed with this work for additional information
@@ -20,7 +20,6 @@ package org.apache.hadoop.hbase.client;
 import static org.junit.Assert.assertArrayEquals;
 import static org.junit.Assert.assertNull;
 import static org.junit.Assert.assertTrue;
-
 import java.io.IOException;
 import java.util.ArrayList;
 import java.util.List;
@@ -53,7 +52,6 @@ import org.junit.BeforeClass;
 import org.junit.ClassRule;
 import org.junit.Test;
 import org.junit.experimental.categories.Category;
-
 import org.apache.hbase.thirdparty.com.google.common.io.Closeables;
 import org.apache.hbase.thirdparty.com.google.protobuf.Descriptors.MethodDescriptor;
 
@@ -90,7 +88,7 @@ public class TestAsyncClientPauseForCallQueueTooBig {
     }
 
     @Override
-    public boolean dispatch(CallRunner callTask) throws InterruptedException {
+    public boolean dispatch(CallRunner callTask) {
       if (FAIL) {
         MethodDescriptor method = callTask.getRpcCall().getMethod();
         // this is for test scan, where we will send a open scanner first and then a next, and we

hbase-server/src/test/java/org/apache/hadoop/hbase/ipc/DelegatingRpcScheduler.java

@@ -1,4 +1,4 @@
-/**
+/*
  * Licensed to the Apache Software Foundation (ASF) under one
  * or more contributor license agreements.  See the NOTICE file
  * distributed with this work for additional information
@@ -18,8 +18,6 @@
 
 package org.apache.hadoop.hbase.ipc;
 
-import java.io.IOException;
-
 public class DelegatingRpcScheduler extends RpcScheduler {
   protected RpcScheduler delegate;
 
@@ -75,7 +73,7 @@ public class DelegatingRpcScheduler extends RpcScheduler {
   }
 
   @Override
-  public boolean dispatch(CallRunner task) throws IOException, InterruptedException {
+  public boolean dispatch(CallRunner task) {
     return delegate.dispatch(task);
   }