HDFS-15507. [JDK 11] Fix javadoc errors in hadoop-hdfs-client module. Contributed by Xieming Li.

hadoop-hdfs-project/hadoop-hdfs-client/pom.xml

@@ -31,7 +31,6 @@ https://maven.apache.org/xsd/maven-4.0.0.xsd">
 
   <properties>
     <hadoop.component>hdfs</hadoop.component>
-    <javadoc.skip.jdk11>true</javadoc.skip.jdk11>
   </properties>
 
   <dependencies>

hadoop-hdfs-project/hadoop-hdfs-client/src/main/java/org/apache/hadoop/hdfs/ClientGSIContext.java

@@ -29,7 +29,7 @@ import java.util.concurrent.atomic.LongAccumulator;
 
 /**
  * Global State Id context for the client.
- * <p/>
+ * <p>
  * This is the client side implementation responsible for receiving
  * state alignment info from server(s).
  */

hadoop-hdfs-project/hadoop-hdfs-client/src/main/java/org/apache/hadoop/hdfs/DFSClient.java

@@ -1241,7 +1241,7 @@ public class DFSClient implements java.io.Closeable, RemotePeerFactory,
 
   /**
    * Same as {@link #create(String, FsPermission, EnumSet, boolean, short, long,
-   * addition of Progressable, int, ChecksumOpt, InetSocketAddress[], String)}
+   * Progressable, int, ChecksumOpt, InetSocketAddress[], String)}
    * with the storagePolicy that is used to specify a specific storage policy
    * instead of inheriting any policy from this new file's parent directory.
    * This policy will be persisted in HDFS. A value of null means inheriting

hadoop-hdfs-project/hadoop-hdfs-client/src/main/java/org/apache/hadoop/hdfs/protocol/HdfsConstants.java

@@ -22,6 +22,7 @@ import java.util.Map;
 
 import org.apache.hadoop.classification.InterfaceAudience;
 import org.apache.hadoop.fs.Path;
+import org.apache.hadoop.hdfs.client.HdfsClientConfigKeys;
 import org.apache.hadoop.util.StringUtils;
 
 @InterfaceAudience.Private
@@ -158,7 +159,7 @@ public final class HdfsConstants {
    * period, no other client can write to the file. The writing client can
    * periodically renew the lease. When the file is closed, the lease is
    * revoked. The lease duration is bound by this soft limit and a
-   * {@link HdfsConstants#LEASE_HARDLIMIT_PERIOD hard limit}. Until the
+   * {@link HdfsClientConfigKeys#DFS_LEASE_HARDLIMIT_KEY }. Until the
    * soft limit expires, the writer has sole write access to the file. If the
    * soft limit expires and the client fails to close the file or renew the
    * lease, another client can preempt the lease.