HBASE-16711 Fix hadoop-3.0 profile compile

Eliminates use of removed or deprecated hadoop2 api
- MBeanUtil -> MBeans Hadoop2 has both; Hadoop 3 removes MBeanUtil and uses MBeans
- FSDataOutputStream(OutputStream) -> FSDataOutputStream(OutputStream, FileSystem.Statistics)
- MetricsServlet is removed.  See HADOOP-12504

hbase-server/src/main/java/org/apache/hadoop/hbase/http/HttpServer.java

@@ -59,7 +59,6 @@ import org.apache.hadoop.hbase.http.jmx.JMXJsonServlet;
 import org.apache.hadoop.hbase.http.log.LogLevel;
 import org.apache.hadoop.hbase.util.Threads;
 import org.apache.hadoop.hbase.util.ReflectionUtils;
-import org.apache.hadoop.metrics.MetricsServlet;
 import org.apache.hadoop.security.SecurityUtil;
 import org.apache.hadoop.security.UserGroupInformation;
 import org.apache.hadoop.security.authentication.server.AuthenticationFilter;
@@ -710,7 +709,17 @@ public class HttpServer implements FilterContainer {
     // set up default servlets
     addServlet("stacks", "/stacks", StackServlet.class);
     addServlet("logLevel", "/logLevel", LogLevel.Servlet.class);
-    addServlet("metrics", "/metrics", MetricsServlet.class);
+
+    // Hadoop3 has moved completely to metrics2, and  dropped support for Metrics v1's
+    // MetricsServlet (see HADOOP-12504).  We'll using reflection to load if against hadoop2.
+    // Remove when we drop support for hbase on hadoop2.x.
+    try {
+      Class clz = Class.forName("org.apache.hadoop.metrics.MetricsServlet");
+      addServlet("metrics", "/metrics", clz);
+    } catch (Exception e) {
+      // do nothing
+    }
+
     addServlet("jmx", "/jmx", JMXJsonServlet.class);
     addServlet("conf", "/conf", ConfServlet.class);
   }

hbase-server/src/main/java/org/apache/hadoop/hbase/regionserver/HRegionServer.java

@@ -190,7 +190,7 @@ import org.apache.hadoop.hbase.zookeeper.ZKUtil;
 import org.apache.hadoop.hbase.zookeeper.ZooKeeperNodeTracker;
 import org.apache.hadoop.hbase.zookeeper.ZooKeeperWatcher;
 import org.apache.hadoop.ipc.RemoteException;
-import org.apache.hadoop.metrics.util.MBeanUtil;
+import org.apache.hadoop.metrics2.util.MBeans;
 import org.apache.hadoop.util.ReflectionUtils;
 import org.apache.hadoop.util.StringUtils;
 import org.apache.zookeeper.KeeperException;
@@ -1031,7 +1031,7 @@ public class HRegionServer extends HasThread implements
     }
     // Run shutdown.
     if (mxBean != null) {
-      MBeanUtil.unregisterMBean(mxBean);
+      MBeans.unregister(mxBean);
       mxBean = null;
     }
     if (this.leases != null) this.leases.closeAfterLeasesExpire();

hbase-server/src/test/java/org/apache/hadoop/hbase/regionserver/TestBulkLoad.java

@@ -273,7 +273,7 @@ public class TestBulkLoad {
     HFile.WriterFactory hFileFactory = HFile.getWriterFactoryNoCache(conf);
     // TODO We need a way to do this without creating files
     File hFileLocation = testFolder.newFile();
-    FSDataOutputStream out = new FSDataOutputStream(new FileOutputStream(hFileLocation));
+    FSDataOutputStream out = new FSDataOutputStream(new FileOutputStream(hFileLocation), null);
     try {
       hFileFactory.withOutputStream(out);
       hFileFactory.withFileContext(new HFileContext());

hbase-thrift/src/main/java/org/apache/hadoop/hbase/thrift/IncrementCoalescer.java

@@ -40,7 +40,7 @@ import org.apache.hadoop.hbase.thrift.ThriftServerRunner.HBaseHandler;
 import org.apache.hadoop.hbase.thrift.generated.TIncrement;
 import org.apache.hadoop.hbase.util.Bytes;
 import org.apache.hadoop.hbase.util.Threads;
-import org.apache.hadoop.metrics.util.MBeanUtil;
+import org.apache.hadoop.metrics2.util.MBeans;
 import org.apache.thrift.TException;
 
 /**
@@ -171,7 +171,7 @@ public class IncrementCoalescer implements IncrementCoalescerMBean {
         new ThreadPoolExecutor(CORE_POOL_SIZE, CORE_POOL_SIZE, 50, TimeUnit.MILLISECONDS, queue,
             Threads.newDaemonThreadFactory("IncrementCoalescer"));
 
-    MBeanUtil.registerMBean("thrift", "Thrift", this);
+    MBeans.register("thrift", "Thrift", this);
   }
 
   public boolean queueIncrement(TIncrement inc) throws TException {