HDFS-17361. Fix UT and Checkstytle

Author: haiyang1987

hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/server/diskbalancer/command/TestDiskBalancerCommand.java

@@ -820,11 +820,11 @@ private List<String> runCommand(
    */
   @Test
   public void testDiskBalancerQueryWithoutSubmitAndMultipleNodes() throws Exception {
-    Configuration conf = new HdfsConfiguration();
-    conf.setBoolean(DFSConfigKeys.DFS_DISK_BALANCER_ENABLED, true);
+    Configuration hdfsConf = new HdfsConfiguration();
+    hdfsConf.setBoolean(DFSConfigKeys.DFS_DISK_BALANCER_ENABLED, true);
     final int numDatanodes = 2;
     File basedir = new File(GenericTestUtils.getRandomizedTempPath());
-    MiniDFSCluster miniDFSCluster = new MiniDFSCluster.Builder(conf, basedir)
+    MiniDFSCluster miniDFSCluster = new MiniDFSCluster.Builder(hdfsConf, basedir)
         .numDataNodes(numDatanodes).build();
     try {
       miniDFSCluster.waitActive();
@@ -834,8 +834,8 @@ public void testDiskBalancerQueryWithoutSubmitAndMultipleNodes() throws Exceptio
           .getIpcPort(), dataNode2.getIpcPort());
       final String cmdLine = String.format("hdfs diskbalancer %s", queryArg);
       List<String> outputs = runCommand(cmdLine);
-      assertTrue(outputs.get(1).contains("localhost:" + dataNode1.getIpcPort()));
-      assertTrue(outputs.get(6).contains("localhost:" + dataNode2.getIpcPort()));
+      assertThat(outputs.get(1), containsString("localhost:" + dataNode1.getIpcPort()));
+      assertThat(outputs.get(6), containsString("localhost:" + dataNode2.getIpcPort()));
     } finally {
       miniDFSCluster.shutdown();
     }
@@ -847,11 +847,11 @@ public void testDiskBalancerQueryWithoutSubmitAndMultipleNodes() throws Exceptio
    */
   @Test
   public void testDiskBalancerQueryWithoutSubmit() throws Exception {
-    Configuration conf = new HdfsConfiguration();
-    conf.setBoolean(DFSConfigKeys.DFS_DISK_BALANCER_ENABLED, true);
+    Configuration hdfsConf = new HdfsConfiguration();
+    hdfsConf.setBoolean(DFSConfigKeys.DFS_DISK_BALANCER_ENABLED, true);
     final int numDatanodes = 2;
     File basedir = new File(GenericTestUtils.getRandomizedTempPath());
-    MiniDFSCluster miniDFSCluster = new MiniDFSCluster.Builder(conf, basedir)
+    MiniDFSCluster miniDFSCluster = new MiniDFSCluster.Builder(hdfsConf, basedir)
         .numDataNodes(numDatanodes).build();
     try {
       miniDFSCluster.waitActive();