Completion FSTs to be loaded off-heap at all times

lucene/suggest/src/java/org/apache/lucene/search/suggest/document/Completion101PostingsFormat.java

@@ -25,17 +25,9 @@
  * @lucene.experimental
  */
 public class Completion101PostingsFormat extends CompletionPostingsFormat {
-  /** Creates a {@link Completion101PostingsFormat} that will load the completion FST on-heap. */
+  /** Creates a {@link Completion101PostingsFormat} that will load the completion FST off-heap. */
   public Completion101PostingsFormat() {
-    this(FSTLoadMode.ON_HEAP);
-  }
-
-  /**
-   * Creates a {@link Completion101PostingsFormat} that will use the provided <code>fstLoadMode
-   * </code> to determine if the completion FST should be loaded on or off heap.
-   */
-  public Completion101PostingsFormat(FSTLoadMode fstLoadMode) {
-    super("Completion101", fstLoadMode);
+    super("Completion101", FSTLoadMode.OFF_HEAP);
   }
 
   @Override

lucene/suggest/src/java/org/apache/lucene/search/suggest/document/Completion50PostingsFormat.java

@@ -27,17 +27,9 @@
  * @lucene.experimental
  */
 public class Completion50PostingsFormat extends CompletionPostingsFormat {
-  /** Creates a {@link Completion50PostingsFormat} that will load the completion FST on-heap. */
+  /** Creates a {@link Completion50PostingsFormat} that will load the completion FST off-heap. */
   public Completion50PostingsFormat() {
-    this(FSTLoadMode.ON_HEAP);
-  }
-
-  /**
-   * Creates a {@link Completion50PostingsFormat} that will use the provided <code>fstLoadMode
-   * </code> to determine if the completion FST should be loaded on or off heap.
-   */
-  public Completion50PostingsFormat(FSTLoadMode fstLoadMode) {
-    super("completion", fstLoadMode);
+    super("completion", FSTLoadMode.OFF_HEAP);
   }
 
   @Override

lucene/suggest/src/java/org/apache/lucene/search/suggest/document/Completion84PostingsFormat.java

@@ -27,17 +27,9 @@
  * @lucene.experimental
  */
 public class Completion84PostingsFormat extends CompletionPostingsFormat {
-  /** Creates a {@link Completion84PostingsFormat} that will load the completion FST on-heap. */
+  /** Creates a {@link Completion84PostingsFormat} that will load the completion FST off-heap. */
   public Completion84PostingsFormat() {
-    this(FSTLoadMode.ON_HEAP);
-  }
-
-  /**
-   * Creates a {@link Completion84PostingsFormat} that will use the provided <code>fstLoadMode
-   * </code> to determine if the completion FST should be loaded on or off heap.
-   */
-  public Completion84PostingsFormat(FSTLoadMode fstLoadMode) {
-    super("Completion84", fstLoadMode);
+    super("Completion84", FSTLoadMode.OFF_HEAP);
   }
 
   @Override

lucene/suggest/src/java/org/apache/lucene/search/suggest/document/Completion90PostingsFormat.java

@@ -27,17 +27,9 @@
  * @lucene.experimental
  */
 public class Completion90PostingsFormat extends CompletionPostingsFormat {
-  /** Creates a {@link Completion90PostingsFormat} that will load the completion FST on-heap. */
+  /** Creates a {@link Completion90PostingsFormat} that will load the completion FST off-heap. */
   public Completion90PostingsFormat() {
-    this(FSTLoadMode.ON_HEAP);
-  }
-
-  /**
-   * Creates a {@link Completion90PostingsFormat} that will use the provided <code>fstLoadMode
-   * </code> to determine if the completion FST should be loaded on or off heap.
-   */
-  public Completion90PostingsFormat(FSTLoadMode fstLoadMode) {
-    super("Completion90", fstLoadMode);
+    super("Completion90", FSTLoadMode.OFF_HEAP);
   }
 
   @Override

lucene/suggest/src/java/org/apache/lucene/search/suggest/document/Completion912PostingsFormat.java

@@ -27,17 +27,9 @@
  * @lucene.experimental
  */
 public class Completion912PostingsFormat extends CompletionPostingsFormat {
-  /** Creates a {@link Completion912PostingsFormat} that will load the completion FST on-heap. */
+  /** Creates a {@link Completion912PostingsFormat} that will load the completion FST off-heap. */
   public Completion912PostingsFormat() {
-    this(FSTLoadMode.ON_HEAP);
-  }
-
-  /**
-   * Creates a {@link Completion912PostingsFormat} that will use the provided <code>fstLoadMode
-   * </code> to determine if the completion FST should be loaded on or off heap.
-   */
-  public Completion912PostingsFormat(FSTLoadMode fstLoadMode) {
-    super("Completion912", fstLoadMode);
+    super("Completion912", FSTLoadMode.OFF_HEAP);
   }
 
   @Override

lucene/suggest/src/java/org/apache/lucene/search/suggest/document/Completion99PostingsFormat.java

@@ -27,17 +27,9 @@
  * @lucene.experimental
  */
 public class Completion99PostingsFormat extends CompletionPostingsFormat {
-  /** Creates a {@link Completion99PostingsFormat} that will load the completion FST on-heap. */
+  /** Creates a {@link Completion99PostingsFormat} that will load the completion FST off-heap. */
   public Completion99PostingsFormat() {
-    this(FSTLoadMode.ON_HEAP);
-  }
-
-  /**
-   * Creates a {@link Completion99PostingsFormat} that will use the provided <code>fstLoadMode
-   * </code> to determine if the completion FST should be loaded on or off heap.
-   */
-  public Completion99PostingsFormat(FSTLoadMode fstLoadMode) {
-    super("Completion99", fstLoadMode);
+    super("Completion99", FSTLoadMode.OFF_HEAP);
   }
 
   @Override

lucene/suggest/src/java/org/apache/lucene/search/suggest/document/CompletionFieldsProducer.java

@@ -56,7 +56,7 @@
 final class CompletionFieldsProducer extends FieldsProducer implements Accountable {
 
   private FieldsProducer delegateFieldsProducer;
-  private Map<String, CompletionsTermsReader> readers;
+  private final Map<String, CompletionsTermsReader> readers;
   private IndexInput dictIn;
 
   // copy ctr for merge instance

lucene/suggest/src/java/org/apache/lucene/search/suggest/document/CompletionPostingsFormat.java

@@ -122,11 +122,6 @@ public enum FSTLoadMode {
 
   private final FSTLoadMode fstLoadMode;
 
-  /** Used only by core Lucene at read-time via Service Provider instantiation */
-  public CompletionPostingsFormat(String name) {
-    this(name, FSTLoadMode.ON_HEAP);
-  }
-
   /**
    * Creates a {@link CompletionPostingsFormat} that will use the provided <code>fstLoadMode</code>
    * to determine if the completion FST should be loaded on or off heap.

lucene/suggest/src/test/org/apache/lucene/search/suggest/document/TestSuggestField.java

@@ -951,7 +951,15 @@ static IndexWriterConfig iwcWithSuggestField(Analyzer analyzer, final Set<String
         new FilterCodec(TestUtil.getDefaultCodec().getName(), TestUtil.getDefaultCodec()) {
           final CompletionPostingsFormat.FSTLoadMode fstLoadMode =
               RandomPicks.randomFrom(random(), CompletionPostingsFormat.FSTLoadMode.values());
-          final PostingsFormat postingsFormat = new Completion101PostingsFormat(fstLoadMode);
+          //FST load mode can only be overridden via a custom completion postings format
+          final PostingsFormat postingsFormat = new CompletionPostingsFormat("Completion101",  fstLoadMode) {
+            final CompletionPostingsFormat delegate = new Completion101PostingsFormat();
+
+            @Override
+            protected PostingsFormat delegatePostingsFormat() {
+              return delegate.delegatePostingsFormat();
+            }
+          };
 
           @Override
           public PostingsFormat postingsFormat() {