LUCENE-10066: Build does not work with JDK16 as gradle's runtime

gradle/generation/local-settings.gradle

@@ -35,33 +35,48 @@ configure(rootProject) {
         def testsJvms = (int) Math.max(1d, Math.min(cpus * 0.5d, 12))
 
         // Write the defaults for this machine.
-        rootProject.file("gradle.properties").write(
-            [
-                "# These settings have been generated automatically on the first run.",
-                "# See gradlew :helpLocalSettings for more information.",
-                "systemProp.file.encoding=UTF-8",
-                "org.gradle.jvmargs=-Xmx3g", // TODO figure out why "gradlew check" runs out of memory if 2g
-                "org.gradle.parallel=true",
-                "org.gradle.priority=normal",
-                "org.gradle.warning.mode=none", // Silence gradle warnings. We'll deal with them when we upgrade the wrapper.
-                "",
-                "# You may disable the background daemon if it consumes too much memory.",
-                "org.gradle.daemon=true",
-                "org.gradle.daemon.idletimeout=900000", // timeout after 15 mins.
-                "",
-                "# Maximum number of parallel gradle workers.",
-                "org.gradle.workers.max=${maxWorkers}",
-                "",
-                "# Maximum number of test JVMs forked per test task.",
-                "tests.jvms=${testsJvms}",
-                "",
-                "# Disable auto JVM provisioning",
-                "org.gradle.java.installations.auto-download=false",
-                "",
-                "# Set these to enable automatic JVM location discovery.",
-                "# org.gradle.java.installations.fromEnv=JDK11,JDK12,JDK13,JDK14,JDK15,JDK16,JDK17",
-                "# org.gradle.java.installations.paths=(custom paths)",
-            ].join("\n"), "UTF-8")
+        rootProject.file("gradle.properties").write("""
+# These settings have been generated automatically on the first run.
+# See gradlew :helpLocalSettings for more information.
+systemProp.file.encoding=UTF-8
+
+# Set up gradle JVM defaults.
+# The heap seems huge but gradle runs out of memory on lower values (don't know why).
+#
+# We also open up internal compiler modules for spotless/ google jaa format.
+org.gradle.jvmargs=-Xmx3g \\
+ --add-exports jdk.compiler/com.sun.tools.javac.api=ALL-UNNAMED \\
+ --add-exports jdk.compiler/com.sun.tools.javac.file=ALL-UNNAMED \\
+ --add-exports jdk.compiler/com.sun.tools.javac.parser=ALL-UNNAMED \\
+ --add-exports jdk.compiler/com.sun.tools.javac.tree=ALL-UNNAMED \\
+ --add-exports jdk.compiler/com.sun.tools.javac.util=ALL-UNNAMED
+
+# Run at normal priority, in parallel
+org.gradle.parallel=true
+org.gradle.priority=normal
+
+# Silence gradle warnings. We'll deal with them when we upgrade the wrapper.
+org.gradle.warning.mode=none
+
+# You may disable the background daemon if it consumes too much memory.
+org.gradle.daemon=true
+# timeout after 15 mins of inactivity.
+org.gradle.daemon.idletimeout=900000
+
+# Maximum number of parallel gradle workers.
+org.gradle.workers.max=${maxWorkers}
+
+# Maximum number of test JVMs forked per test task.
+tests.jvms=${testsJvms}
+
+# Disable auto JVM provisioning (we don't use toolchains yet but want no surprises).
+org.gradle.java.installations.auto-download=false
+
+# Set these to enable automatic JVM location discovery.
+org.gradle.java.installations.fromEnv=JDK11,JDK12,JDK13,JDK14,JDK15,JDK16,JDK17
+org.gradle.java.installations.paths=(custom paths)
+
+""", "UTF-8")
 
         logger.log(LogLevel.WARN, "\nIMPORTANT. This is the first time you ran the build. " +
             "I wrote some sane defaults (for this machine) to 'gradle.properties', " +

gradle/validation/spotless.gradle

@@ -37,7 +37,7 @@ configure(project(":lucene").subprojects) { prj ->
 
         lineEndings 'UNIX'
         endWithNewline()
-        googleJavaFormat('1.9')
+        googleJavaFormat('1.11.0')
 
         // Apply to all Java sources
         target "src/**/*.java"

lucene/backward-codecs/src/test/org/apache/lucene/backward_codecs/lucene87/Lucene87RWStoredFieldsFormat.java

@@ -24,8 +24,6 @@
 import org.apache.lucene.store.Directory;
 import org.apache.lucene.store.IOContext;
 
-;
-
 /** RW impersonation of Lucene87StoredFieldsFormat. */
 public class Lucene87RWStoredFieldsFormat extends Lucene87StoredFieldsFormat {
 

lucene/core/src/java/org/apache/lucene/util/fst/PositiveIntOutputs.java

@@ -30,7 +30,8 @@
 @SuppressForbidden(reason = "Uses a Long instance as a marker")
 public final class PositiveIntOutputs extends Outputs<Long> {
 
-  @SuppressWarnings("deprecation")
+  // Ignore the deprecated constructor. We do want a unique object here.
+  @SuppressWarnings({"all"})
   private static final Long NO_OUTPUT = new Long(0);
 
   private static final PositiveIntOutputs singleton = new PositiveIntOutputs();

lucene/core/src/test/org/apache/lucene/analysis/TestCharArraySet.java

@@ -57,7 +57,7 @@ public void testNonZeroOffset() {
   public void testObjectContains() {
     CharArraySet set = new CharArraySet(10, true);
     Integer val = Integer.valueOf(1);
-    @SuppressWarnings("deprecation")
+    @SuppressWarnings("all")
     Integer val1 = new Integer(1);
     // Verify explicitly the case of different Integer instances
     assertNotSame(val, val1);

lucene/misc/src/java/org/apache/lucene/misc/util/fst/UpToTwoPositiveIntOutputs.java

@@ -76,7 +76,8 @@ public int hashCode() {
     }
   }
 
-  @SuppressWarnings("deprecation")
+  // Ignore the deprecated constructor. We do want a unique object here.
+  @SuppressWarnings({"all"})
   private static final Long NO_OUTPUT = new Long(0);
 
   private final boolean doShare;