HADOOP-18241. Move to JAVA 11.

dev-support/Jenkinsfile

@@ -47,7 +47,7 @@ pipeline {
 
     options {
         buildDiscarder(logRotator(numToKeepStr: '5'))
-        timeout (time: 24, unit: 'HOURS')
+        timeout (time: 48, unit: 'HOURS')
         timestamps()
         checkoutToSubdirectory('src')
     }

dev-support/docker/Dockerfile

@@ -58,7 +58,7 @@ ENV PYTHONIOENCODING=utf-8
 ######
 ENV MAVEN_HOME /usr
 # JAVA_HOME must be set in Maven >= 3.5.0 (MNG-6003)
-ENV JAVA_HOME /usr/lib/jvm/java-8-openjdk-amd64
+ENV JAVA_HOME /usr/lib/jvm/java-11-openjdk-amd64
 
 #######
 # Set env vars for SpotBugs 4.2.2

dev-support/docker/Dockerfile_aarch64

@@ -58,7 +58,7 @@ ENV PYTHONIOENCODING=utf-8
 ######
 ENV MAVEN_HOME /usr
 # JAVA_HOME must be set in Maven >= 3.5.0 (MNG-6003)
-ENV JAVA_HOME /usr/lib/jvm/java-8-openjdk-arm64
+ENV JAVA_HOME /usr/lib/jvm/java-11-openjdk-arm64
 
 #######
 # Set env vars for SpotBugs 4.2.2

dev-support/docker/Dockerfile_centos_7

@@ -62,13 +62,16 @@ ENV INFOPATH "${GCC_HOME}/root/usr/share/info"
 
 # TODO: Set locale
 
+#Install java 11
+RUN yum install -y java-11-openjdk-devel
+
 ######
 # Set env vars required to build Hadoop
 ######
 ENV MAVEN_HOME /opt/maven
 ENV PATH "${PATH}:${MAVEN_HOME}/bin"
 # JAVA_HOME must be set in Maven >= 3.5.0 (MNG-6003)
-ENV JAVA_HOME /usr/lib/jvm/java-1.8.0
+ENV JAVA_HOME /usr/lib/jvm/java-11-openjdk/
 
 #######
 # Set env vars for SpotBugs

dev-support/docker/Dockerfile_centos_8

@@ -87,13 +87,16 @@ ENV INFOPATH "${GCC_HOME}/root/usr/share/info"
 
 # TODO: Set locale
 
+#Install java 11
+RUN yum -y install java-11-openjdk java-11-openjdk-devel
+
 ######
 # Set env vars required to build Hadoop
 ######
 ENV MAVEN_HOME /opt/maven
 ENV PATH "${PATH}:${MAVEN_HOME}/bin"
 # JAVA_HOME must be set in Maven >= 3.5.0 (MNG-6003)
-ENV JAVA_HOME /usr/lib/jvm/java-1.8.0
+ENV JAVA_HOME /usr/lib/jvm/java-11-openjdk/
 
 #######
 # Set env vars for SpotBugs

dev-support/docker/pkg-resolver/packages.json

@@ -261,11 +261,9 @@
   "java": {
     "debian:10": "openjdk-11-jdk",
     "ubuntu:focal": [
-      "openjdk-8-jdk",
       "openjdk-11-jdk"
     ],
     "ubuntu:focal::arch64": [
-      "openjdk-8-jdk",
       "openjdk-11-jdk"
     ]
   },

dev-support/jenkins.sh

@@ -187,10 +187,8 @@ function run_ci() {
   # help keep the ASF boxes clean
   YETUS_ARGS+=("--sentinel")
 
-  # test with Java 8 and 11
-  YETUS_ARGS+=("--java-home=/usr/lib/jvm/java-8-openjdk-amd64")
-  YETUS_ARGS+=("--multijdkdirs=/usr/lib/jvm/java-11-openjdk-amd64")
-  YETUS_ARGS+=("--multijdktests=compile")
+  # test with Java 11
+  YETUS_ARGS+=("--java-home=/usr/lib/jvm/java-11-openjdk-amd64")
 
   # custom javadoc goals
   YETUS_ARGS+=("--mvn-javadoc-goals=process-sources,javadoc:javadoc-no-fork")

hadoop-common-project/hadoop-annotations/pom.xml

@@ -38,21 +38,6 @@
   </dependencies>
 
   <profiles>
-    <profile>
-      <id>jdk1.8</id>
-      <activation>
-        <jdk>1.8</jdk>
-      </activation>
-      <dependencies>
-        <dependency>
-          <groupId>jdk.tools</groupId>
-          <artifactId>jdk.tools</artifactId>
-          <version>1.8</version>
-          <scope>system</scope>
-          <systemPath>${java.home}/../lib/tools.jar</systemPath>
-        </dependency>
-      </dependencies>
-    </profile>
     <profile>
       <id>jdk10</id>
       <activation>

hadoop-common-project/hadoop-common/src/main/java/org/apache/hadoop/conf/Configuration.java

@@ -127,10 +127,10 @@
  *
  * <p>Unless explicitly turned off, Hadoop by default specifies two 
  * resources, loaded in-order from the classpath: <ol>
- * <li><tt>
+ * <li><code>
  * <a href="{@docRoot}/../hadoop-project-dist/hadoop-common/core-default.xml">
- * core-default.xml</a></tt>: Read-only defaults for hadoop.</li>
- * <li><tt>core-site.xml</tt>: Site-specific configuration for a given hadoop
+ * core-default.xml</a></code>: Read-only defaults for hadoop.</li>
+ * <li><code>core-site.xml</code>: Site-specific configuration for a given hadoop
  * installation.</li>
  * </ol>
  * Applications may add additional resources, which are loaded
@@ -150,7 +150,7 @@
  *  &lt;/property&gt;</code></pre>
  *
  * Administrators typically define parameters as final in 
- * <tt>core-site.xml</tt> for values that user applications may not alter.
+ * <code>core-site.xml</code> for values that user applications may not alter.
  *
  * <h4 id="VariableExpansion">Variable Expansion</h4>
  *
@@ -182,19 +182,19 @@
  *  &lt;/property&gt;
  *  </code></pre>
  *
- * <p>When <tt>conf.get("tempdir")</tt> is called, then <tt>${<i>basedir</i>}</tt>
+ * <p>When <code>conf.get("tempdir")</code> is called, then <code>${<i>basedir</i>}</code>
  * will be resolved to another property in this Configuration, while
- * <tt>${<i>user.name</i>}</tt> would then ordinarily be resolved to the value
+ * <code>${<i>user.name</i>}</code> would then ordinarily be resolved to the value
  * of the System property with that name.
- * <p>When <tt>conf.get("otherdir")</tt> is called, then <tt>${<i>env.BASE_DIR</i>}</tt>
- * will be resolved to the value of the <tt>${<i>BASE_DIR</i>}</tt> environment variable.
- * It supports <tt>${<i>env.NAME:-default</i>}</tt> and <tt>${<i>env.NAME-default</i>}</tt> notations.
- * The former is resolved to "default" if <tt>${<i>NAME</i>}</tt> environment variable is undefined
+ * <p>When <code>conf.get("otherdir")</code> is called, then <code>${<i>env.BASE_DIR</i>}</code>
+ * will be resolved to the value of the <code>${<i>BASE_DIR</i>}</code> environment variable.
+ * It supports <code>${<i>env.NAME:-default</i>}</code> and <code>${<i>env.NAME-default</i>}</code> notations.
+ * The former is resolved to "default" if <code>${<i>NAME</i>}</code> environment variable is undefined
  * or its value is empty.
- * The latter behaves the same way only if <tt>${<i>NAME</i>}</tt> is undefined.
+ * The latter behaves the same way only if <code>${<i>NAME</i>}</code> is undefined.
  * <p>By default, warnings will be given to any deprecated configuration 
  * parameters and these are suppressible by configuring
- * <tt>log4j.logger.org.apache.hadoop.conf.Configuration.deprecation</tt> in
+ * <code>log4j.logger.org.apache.hadoop.conf.Configuration.deprecation</code> in
  * log4j.properties file.
  *
  * <h4 id="Tags">Tags</h4>
@@ -217,9 +217,9 @@
  *    &lt;tag&gt;HDFS,SECURITY&lt;/tag&gt;
  *  &lt;/property&gt;
  * </code></pre>
- * <p> Properties marked with tags can be retrieved with <tt>conf
- * .getAllPropertiesByTag("HDFS")</tt> or <tt>conf.getAllPropertiesByTags
- * (Arrays.asList("YARN","SECURITY"))</tt>.</p>
+ * <p> Properties marked with tags can be retrieved with <code>conf
+ * .getAllPropertiesByTag("HDFS")</code> or <code>conf.getAllPropertiesByTags
+ * (Arrays.asList("YARN","SECURITY"))</code>.</p>
  */
 @InterfaceAudience.Public
 @InterfaceStability.Stable
@@ -573,7 +573,7 @@ public static void addDeprecations(DeprecationDelta[] deltas) {
    * It does not override any existing entries in the deprecation map.
    * This is to be used only by the developers in order to add deprecation of
    * keys, and attempts to call this method after loading resources once,
-   * would lead to <tt>UnsupportedOperationException</tt>
+   * would lead to <code>UnsupportedOperationException</code>
    * 
    * If a key is deprecated in favor of multiple keys, they are all treated as 
    * aliases of each other, and setting any one of them resets all the others 
@@ -601,7 +601,7 @@ public static void addDeprecation(String key, String[] newKeys,
    * It does not override any existing entries in the deprecation map.
    * This is to be used only by the developers in order to add deprecation of
    * keys, and attempts to call this method after loading resources once,
-   * would lead to <tt>UnsupportedOperationException</tt>
+   * would lead to <code>UnsupportedOperationException</code>
    * 
    * If you have multiple deprecation entries to add, it is more efficient to
    * use #addDeprecations(DeprecationDelta[] deltas) instead.
@@ -621,7 +621,7 @@ public static void addDeprecation(String key, String newKey,
    * It does not override any existing entries in the deprecation map.
    * This is to be used only by the developers in order to add deprecation of
    * keys, and attempts to call this method after loading resources once,
-   * would lead to <tt>UnsupportedOperationException</tt>
+   * would lead to <code>UnsupportedOperationException</code>
    * 
    * If a key is deprecated in favor of multiple keys, they are all treated as 
    * aliases of each other, and setting any one of them resets all the others 
@@ -645,7 +645,7 @@ public static void addDeprecation(String key, String[] newKeys) {
    * It does not override any existing entries in the deprecation map.
    * This is to be used only by the developers in order to add deprecation of
    * keys, and attempts to call this method after loading resources once,
-   * would lead to <tt>UnsupportedOperationException</tt>
+   * would lead to <code>UnsupportedOperationException</code>
    * 
    * If you have multiple deprecation entries to add, it is more efficient to
    * use #addDeprecations(DeprecationDelta[] deltas) instead.

hadoop-common-project/hadoop-common/src/main/java/org/apache/hadoop/fs/AbstractFileSystem.java

@@ -247,7 +247,7 @@ protected static synchronized Map<URI, Statistics> getAllStatistics() {
    * The main factory method for creating a file system. Get a file system for
    * the URI's scheme and authority. The scheme of the <code>uri</code>
    * determines a configuration property name,
-   * <tt>fs.AbstractFileSystem.<i>scheme</i>.impl</tt> whose value names the
+   * <code>fs.AbstractFileSystem.<i>scheme</i>.impl</code> whose value names the
    * AbstractFileSystem class.
    * 
    * The entire URI and conf is passed to the AbstractFileSystem factory method.

hadoop-common-project/hadoop-common/src/main/java/org/apache/hadoop/fs/ChecksumFileSystem.java

@@ -686,7 +686,7 @@ boolean apply(Path p) throws IOException {
 
   /**
    * Set replication for an existing file.
-   * Implement the abstract <tt>setReplication</tt> of <tt>FileSystem</tt>
+   * Implement the abstract <code>setReplication</code> of <code>FileSystem</code>
    * @param src file name
    * @param replication new replication
    * @throws IOException if an I/O error occurs.

hadoop-common-project/hadoop-common/src/main/java/org/apache/hadoop/fs/ChecksumFs.java

@@ -453,7 +453,7 @@ private boolean isDirectory(Path f)
   }
   /**
    * Set replication for an existing file.
-   * Implement the abstract <tt>setReplication</tt> of <tt>FileSystem</tt>
+   * Implement the abstract <code>setReplication</code> of <code>FileSystem</code>
    * @param src file name
    * @param replication new replication
    * @throws IOException if an I/O error occurs.

hadoop-common-project/hadoop-common/src/main/java/org/apache/hadoop/fs/FileContext.java

@@ -1977,9 +1977,9 @@ public RemoteIterator<LocatedFileStatus> listFiles(
         LocatedFileStatus curFile;
 
         /**
-         * Returns <tt>true</tt> if the iterator has more files.
+         * Returns <code>true</code> if the iterator has more files.
          *
-         * @return <tt>true</tt> if the iterator has more files.
+         * @return <code>true</code> if the iterator has more files.
          * @throws AccessControlException if not allowed to access next
          *                                file's status or locations
          * @throws FileNotFoundException if next file does not exist any more
@@ -2071,34 +2071,34 @@ public LocatedFileStatus next() throws IOException {
      * <dl>
      *  <dd>
      *   <dl>
-     *    <dt> <tt> ? </tt>
+     *    <dt> <code> ? </code>
      *    <dd> Matches any single character.
      *
-     *    <dt> <tt> * </tt>
+     *    <dt> <code> * </code>
      *    <dd> Matches zero or more characters.
      *
-     *    <dt> <tt> [<i>abc</i>] </tt>
+     *    <dt> <code> [<i>abc</i>] </code>
      *    <dd> Matches a single character from character set
-     *     <tt>{<i>a,b,c</i>}</tt>.
+     *     <code>{<i>a,b,c</i>}</code>.
      *
-     *    <dt> <tt> [<i>a</i>-<i>b</i>] </tt>
+     *    <dt> <code> [<i>a</i>-<i>b</i>] </code>
      *    <dd> Matches a single character from the character range
-     *     <tt>{<i>a...b</i>}</tt>. Note: character <tt><i>a</i></tt> must be
-     *     lexicographically less than or equal to character <tt><i>b</i></tt>.
+     *     <code>{<i>a...b</i>}</code>. Note: character <code><i>a</i></code> must be
+     *     lexicographically less than or equal to character <code><i>b</i></code>.
      *
-     *    <dt> <tt> [^<i>a</i>] </tt>
+     *    <dt> <code> [^<i>a</i>] </code>
      *    <dd> Matches a single char that is not from character set or range
-     *     <tt>{<i>a</i>}</tt>.  Note that the <tt>^</tt> character must occur
+     *     <code>{<i>a</i>}</code>.  Note that the <code>^</code> character must occur
      *     immediately to the right of the opening bracket.
      *
-     *    <dt> <tt> \<i>c</i> </tt>
+     *    <dt> <code> \<i>c</i> </code>
      *    <dd> Removes (escapes) any special meaning of character <i>c</i>.
      *
-     *    <dt> <tt> {ab,cd} </tt>
-     *    <dd> Matches a string from the string set <tt>{<i>ab, cd</i>} </tt>
+     *    <dt> <code> {ab,cd} </code>
+     *    <dd> Matches a string from the string set <code>{<i>ab, cd</i>} </code>
      *
-     *    <dt> <tt> {ab,c{de,fh}} </tt>
-     *    <dd> Matches a string from string set <tt>{<i>ab, cde, cfh</i>}</tt>
+     *    <dt> <code> {ab,c{de,fh}} </code>
+     *    <dd> Matches a string from string set <code>{<i>ab, cde, cfh</i>}</code>
      *
      *   </dl>
      *  </dd>

hadoop-common-project/hadoop-common/src/main/java/org/apache/hadoop/fs/FileSystem.java

@@ -2144,34 +2144,34 @@ public FileStatus[] listStatus(Path[] files, PathFilter filter)
    * <dl>
    *  <dd>
    *   <dl>
-   *    <dt> <tt> ? </tt>
+   *    <dt> <code> ? </code>
    *    <dd> Matches any single character.
    *
-   *    <dt> <tt> * </tt>
+   *    <dt> <code> * </code>
    *    <dd> Matches zero or more characters.
    *
-   *    <dt> <tt> [<i>abc</i>] </tt>
+   *    <dt> <code> [<i>abc</i>] </code>
    *    <dd> Matches a single character from character set
-   *     <tt>{<i>a,b,c</i>}</tt>.
+   *     <code>{<i>a,b,c</i>}</code>.
    *
-   *    <dt> <tt> [<i>a</i>-<i>b</i>] </tt>
+   *    <dt> <code> [<i>a</i>-<i>b</i>] </code>
    *    <dd> Matches a single character from the character range
-   *     <tt>{<i>a...b</i>}</tt>.  Note that character <tt><i>a</i></tt> must be
-   *     lexicographically less than or equal to character <tt><i>b</i></tt>.
+   *     <code>{<i>a...b</i>}</code>.  Note that character <code><i>a</i></code> must be
+   *     lexicographically less than or equal to character <code><i>b</i></code>.
    *
-   *    <dt> <tt> [^<i>a</i>] </tt>
+   *    <dt> <code> [^<i>a</i>] </code>
    *    <dd> Matches a single character that is not from character set or range
-   *     <tt>{<i>a</i>}</tt>.  Note that the <tt>^</tt> character must occur
+   *     <code>{<i>a</i>}</code>.  Note that the <code>^</code> character must occur
    *     immediately to the right of the opening bracket.
    *
-   *    <dt> <tt> \<i>c</i> </tt>
+   *    <dt> <code> \<i>c</i> </code>
    *    <dd> Removes (escapes) any special meaning of character <i>c</i>.
    *
-   *    <dt> <tt> {ab,cd} </tt>
-   *    <dd> Matches a string from the string set <tt>{<i>ab, cd</i>} </tt>
+   *    <dt> <code> {ab,cd} </code>
+   *    <dd> Matches a string from the string set <code>{<i>ab, cd</i>} </code>
    *
-   *    <dt> <tt> {ab,c{de,fh}} </tt>
-   *    <dd> Matches a string from the string set <tt>{<i>ab, cde, cfh</i>}</tt>
+   *    <dt> <code> {ab,c{de,fh}} </code>
+   *    <dd> Matches a string from the string set <code>{<i>ab, cde, cfh</i>}</code>
    *
    *   </dl>
    *  </dd>

hadoop-common-project/hadoop-common/src/main/java/org/apache/hadoop/fs/RemoteIterator.java

@@ -24,9 +24,9 @@
  */
 public interface RemoteIterator<E> {
   /**
-   * Returns <tt>true</tt> if the iteration has more elements.
+   * Returns <code>true</code> if the iteration has more elements.
    *
-   * @return <tt>true</tt> if the iterator has more elements.
+   * @return <code>true</code> if the iterator has more elements.
    * @throws IOException if any IO error occurs
    */
   boolean hasNext() throws IOException;

hadoop-common-project/hadoop-common/src/main/java/org/apache/hadoop/io/EnumSetWritable.java

@@ -59,10 +59,10 @@ public boolean add(E e) {
   }
 
   /**
-   * Construct a new EnumSetWritable. If the <tt>value</tt> argument is null or
-   * its size is zero, the <tt>elementType</tt> argument must not be null. If
-   * the argument <tt>value</tt>'s size is bigger than zero, the argument
-   * <tt>elementType</tt> is not be used.
+   * Construct a new EnumSetWritable. If the <code>value</code> argument is null or
+   * its size is zero, the <code>elementType</code> argument must not be null. If
+   * the argument <code>value</code>'s size is bigger than zero, the argument
+   * <code>elementType</code> is not be used.
    * 
    * @param value enumSet value.
    * @param elementType elementType.
@@ -72,7 +72,7 @@ public EnumSetWritable(EnumSet<E> value, Class<E> elementType) {
   }
 
   /**
-   * Construct a new EnumSetWritable. Argument <tt>value</tt> should not be null
+   * Construct a new EnumSetWritable. Argument <code>value</code> should not be null
    * or empty.
    * 
    * @param value enumSet value.
@@ -83,10 +83,10 @@ public EnumSetWritable(EnumSet<E> value) {
 
   /**
    * reset the EnumSetWritable with specified
-   * <tt>value</tt> and <tt>elementType</tt>. If the <tt>value</tt> argument
-   * is null or its size is zero, the <tt>elementType</tt> argument must not be
-   * null. If the argument <tt>value</tt>'s size is bigger than zero, the
-   * argument <tt>elementType</tt> is not be used.
+   * <code>value</code> and <code>elementType</code>. If the <code>value</code> argument
+   * is null or its size is zero, the <code>elementType</code> argument must not be
+   * null. If the argument <code>value</code>'s size is bigger than zero, the
+   * argument <code>elementType</code> is not be used.
    * 
    * @param value enumSet Value.
    * @param elementType elementType.