Merge branch 'stable-2.16' into stable-3.0

* stable-2.16:
  ElasticContainer: Upgrade V6_8 to elasticsearch 6.8.9
  ElasticVersion: Replace unchecked throw w/ javadoc
  Remove obsolete parts from Java code style guide
  Elasticsearch: Remove support for EOL 6.5 version

Change-Id: Iab0ccdf102d510f001400c1ed140edc6014f2536
diff --git a/java/com/google/gerrit/elasticsearch/ElasticVersion.java b/java/com/google/gerrit/elasticsearch/ElasticVersion.java
index 82816fb..fb24cb0 100644
--- a/java/com/google/gerrit/elasticsearch/ElasticVersion.java
+++ b/java/com/google/gerrit/elasticsearch/ElasticVersion.java
@@ -18,7 +18,6 @@
 import java.util.regex.Pattern;
 
 public enum ElasticVersion {
-  V6_5("6.5.*"),
   V6_6("6.6.*"),
   V6_7("6.7.*"),
   V6_8("6.8.*"),
@@ -48,7 +47,14 @@
     }
   }
 
-  public static ElasticVersion forVersion(String version) throws UnsupportedVersion {
+  /**
+   * Convert a version String to an ElasticVersion if supported.
+   *
+   * @param version for which to return an ElasticVersion
+   * @return the corresponding ElasticVersion if supported
+   * @throws UnsupportedVersion
+   */
+  public static ElasticVersion forVersion(String version) {
     for (ElasticVersion value : ElasticVersion.values()) {
       if (value.pattern.matcher(version).matches()) {
         return value;
diff --git a/javatests/com/google/gerrit/elasticsearch/ElasticContainer.java b/javatests/com/google/gerrit/elasticsearch/ElasticContainer.java
index e4b45ed..df3ec5e 100644
--- a/javatests/com/google/gerrit/elasticsearch/ElasticContainer.java
+++ b/javatests/com/google/gerrit/elasticsearch/ElasticContainer.java
@@ -38,14 +38,12 @@
 
   private static String getImageName(ElasticVersion version) {
     switch (version) {
-      case V6_5:
-        return "blacktop/elasticsearch:6.5.4";
       case V6_6:
         return "blacktop/elasticsearch:6.6.2";
       case V6_7:
         return "blacktop/elasticsearch:6.7.2";
       case V6_8:
-        return "blacktop/elasticsearch:6.8.8";
+        return "blacktop/elasticsearch:6.8.9";
       case V7_0:
         return "blacktop/elasticsearch:7.0.1";
       case V7_1:
diff --git a/javatests/com/google/gerrit/elasticsearch/ElasticVersionTest.java b/javatests/com/google/gerrit/elasticsearch/ElasticVersionTest.java
index 6b0c2b1..5667217 100644
--- a/javatests/com/google/gerrit/elasticsearch/ElasticVersionTest.java
+++ b/javatests/com/google/gerrit/elasticsearch/ElasticVersionTest.java
@@ -22,9 +22,6 @@
 public class ElasticVersionTest extends GerritBaseTests {
   @Test
   public void supportedVersion() throws Exception {
-    assertThat(ElasticVersion.forVersion("6.5.0")).isEqualTo(ElasticVersion.V6_5);
-    assertThat(ElasticVersion.forVersion("6.5.1")).isEqualTo(ElasticVersion.V6_5);
-
     assertThat(ElasticVersion.forVersion("6.6.0")).isEqualTo(ElasticVersion.V6_6);
     assertThat(ElasticVersion.forVersion("6.6.1")).isEqualTo(ElasticVersion.V6_6);
 
@@ -66,7 +63,6 @@
 
   @Test
   public void atLeastMinorVersion() throws Exception {
-    assertThat(ElasticVersion.V6_5.isAtLeastMinorVersion(ElasticVersion.V6_7)).isFalse();
     assertThat(ElasticVersion.V6_6.isAtLeastMinorVersion(ElasticVersion.V6_7)).isFalse();
     assertThat(ElasticVersion.V6_7.isAtLeastMinorVersion(ElasticVersion.V6_7)).isTrue();
     assertThat(ElasticVersion.V6_8.isAtLeastMinorVersion(ElasticVersion.V6_8)).isTrue();
@@ -81,7 +77,6 @@
 
   @Test
   public void version6OrLater() throws Exception {
-    assertThat(ElasticVersion.V6_5.isV6OrLater()).isTrue();
     assertThat(ElasticVersion.V6_6.isV6OrLater()).isTrue();
     assertThat(ElasticVersion.V6_7.isV6OrLater()).isTrue();
     assertThat(ElasticVersion.V6_8.isV6OrLater()).isTrue();
@@ -96,7 +91,6 @@
 
   @Test
   public void version7OrLater() throws Exception {
-    assertThat(ElasticVersion.V6_5.isV7OrLater()).isFalse();
     assertThat(ElasticVersion.V6_6.isV7OrLater()).isFalse();
     assertThat(ElasticVersion.V6_7.isV7OrLater()).isFalse();
     assertThat(ElasticVersion.V6_8.isV7OrLater()).isFalse();