Use generics for doc value object types (#745)

src/main/java/com/yelp/nrtsearch/server/luceneserver/field/BooleanFieldDef.java

@@ -36,9 +36,9 @@
 import org.apache.lucene.search.Query;
 
 /** Field class for 'BOOLEAN' field type. */
-public class BooleanFieldDef extends IndexableFieldDef implements TermQueryable {
+public class BooleanFieldDef extends IndexableFieldDef<Boolean> implements TermQueryable {
   protected BooleanFieldDef(String name, Field requestField) {
-    super(name, requestField);
+    super(name, requestField, Boolean.class);
   }
 
   @Override
@@ -113,7 +113,7 @@ public void parseDocumentField(
   }
 
   @Override
-  public LoadedDocValues<?> getDocValues(LeafReaderContext context) throws IOException {
+  public LoadedDocValues<Boolean> getDocValues(LeafReaderContext context) throws IOException {
     if (docValuesType == DocValuesType.NUMERIC) {
       NumericDocValues numericDocValues = DocValues.getNumeric(context.reader(), getName());
       return new LoadedDocValues.SingleBoolean(numericDocValues);

src/main/java/com/yelp/nrtsearch/server/luceneserver/field/ContextSuggestFieldDef.java

@@ -28,7 +28,7 @@
 import org.apache.lucene.search.suggest.document.Completion912PostingsFormat;
 import org.apache.lucene.search.suggest.document.ContextSuggestField;
 
-public class ContextSuggestFieldDef extends IndexableFieldDef {
+public class ContextSuggestFieldDef extends IndexableFieldDef<Void> {
   private static final Gson GSON = new GsonBuilder().serializeNulls().create();
   private final Analyzer indexAnalyzer;
   private final Analyzer searchAnalyzer;
@@ -38,7 +38,7 @@ public class ContextSuggestFieldDef extends IndexableFieldDef {
    * @param requestField field definition from grpc request
    */
   protected ContextSuggestFieldDef(String name, Field requestField) {
-    super(name, requestField);
+    super(name, requestField, Void.class);
     this.indexAnalyzer = this.parseIndexAnalyzer(requestField);
     this.searchAnalyzer = this.parseSearchAnalyzer(requestField);
   }

src/main/java/com/yelp/nrtsearch/server/luceneserver/field/DateTimeFieldDef.java

@@ -45,7 +45,8 @@
 import org.apache.lucene.search.SortField;
 
 /** Field class for 'DATE_TIME' field type. */
-public class DateTimeFieldDef extends IndexableFieldDef implements Sortable, RangeQueryable {
+public class DateTimeFieldDef extends IndexableFieldDef<Instant>
+    implements Sortable, RangeQueryable {
   private static final String EPOCH_MILLIS = "epoch_millis";
   private static final String STRICT_DATE_OPTIONAL_TIME = "strict_date_optional_time";
 
@@ -79,7 +80,7 @@ private static DateTimeFormatter createDateTimeFormatter(String dateTimeFormat)
   }
 
   public DateTimeFieldDef(String name, Field requestField) {
-    super(name, requestField);
+    super(name, requestField, Instant.class);
     dateTimeFormat = requestField.getDateTimeFormat();
     dateTimeFormatter = createDateTimeFormatter(dateTimeFormat);
   }
@@ -278,7 +279,7 @@ private long getTimeFromEpochMillisString(String epochMillisString) {
   }
 
   @Override
-  public LoadedDocValues<?> getDocValues(LeafReaderContext context) throws IOException {
+  public LoadedDocValues<Instant> getDocValues(LeafReaderContext context) throws IOException {
     if (docValuesType == DocValuesType.NUMERIC) {
       NumericDocValues numericDocValues = DocValues.getNumeric(context.reader(), getName());
       return new LoadedDocValues.SingleDateTime(numericDocValues);

src/main/java/com/yelp/nrtsearch/server/luceneserver/field/DoubleFieldDef.java

@@ -35,10 +35,10 @@
 import org.apache.lucene.util.NumericUtils;
 
 /** Field class for 'DOUBLE' field type. */
-public class DoubleFieldDef extends NumberFieldDef {
+public class DoubleFieldDef extends NumberFieldDef<Double> {
 
   public DoubleFieldDef(String name, Field requestField) {
-    super(name, requestField, DOUBLE_PARSER);
+    super(name, requestField, DOUBLE_PARSER, Double.class);
   }
 
   @Override
@@ -59,12 +59,12 @@ protected org.apache.lucene.document.Field getPointField(Number fieldValue) {
   }
 
   @Override
-  protected LoadedDocValues<?> getNumericDocValues(NumericDocValues docValues) {
+  protected LoadedDocValues<Double> getNumericDocValues(NumericDocValues docValues) {
     return new LoadedDocValues.SingleDouble(docValues);
   }
 
   @Override
-  protected LoadedDocValues<?> getSortedNumericDocValues(SortedNumericDocValues docValues) {
+  protected LoadedDocValues<Double> getSortedNumericDocValues(SortedNumericDocValues docValues) {
     return new LoadedDocValues.SortedDoubles(docValues);
   }
 
@@ -160,7 +160,7 @@ public Query getTermQueryFromTextValue(String textValue) {
 
   @Override
   public Query getTermInSetQueryFromTextValues(List<String> textValues) {
-    List<Double> doubleTerms = new ArrayList(textValues.size());
+    List<Double> doubleTerms = new ArrayList<>(textValues.size());
     textValues.forEach((s) -> doubleTerms.add(Double.parseDouble(s)));
     return DoublePoint.newSetQuery(getName(), doubleTerms);
   }

src/main/java/com/yelp/nrtsearch/server/luceneserver/field/FieldDefCreator.java

@@ -60,7 +60,7 @@ public FieldDefCreator(LuceneServerConfiguration configuration) {
         (name, field) -> {
           throw new UnsupportedOperationException("Runtime fields should be created directly");
         });
-    register("VECTOR", VectorFieldDef::new);
+    register("VECTOR", VectorFieldDef::createField);
     register("CONTEXT_SUGGEST", ContextSuggestFieldDef::new);
   }
 

src/main/java/com/yelp/nrtsearch/server/luceneserver/field/FloatFieldDef.java

@@ -35,10 +35,10 @@
 import org.apache.lucene.util.NumericUtils;
 
 /** Field class for 'FLOAT' field type. */
-public class FloatFieldDef extends NumberFieldDef {
+public class FloatFieldDef extends NumberFieldDef<Float> {
 
   public FloatFieldDef(String name, Field requestField) {
-    super(name, requestField, FLOAT_PARSER);
+    super(name, requestField, FLOAT_PARSER, Float.class);
   }
 
   @Override
@@ -59,12 +59,12 @@ protected org.apache.lucene.document.Field getPointField(Number fieldValue) {
   }
 
   @Override
-  protected LoadedDocValues<?> getNumericDocValues(NumericDocValues docValues) {
+  protected LoadedDocValues<Float> getNumericDocValues(NumericDocValues docValues) {
     return new LoadedDocValues.SingleFloat(docValues);
   }
 
   @Override
-  protected LoadedDocValues<?> getSortedNumericDocValues(SortedNumericDocValues docValues) {
+  protected LoadedDocValues<Float> getSortedNumericDocValues(SortedNumericDocValues docValues) {
     return new LoadedDocValues.SortedFloats(docValues);
   }
 
@@ -159,7 +159,7 @@ public Query getTermQueryFromTextValue(String textValue) {
 
   @Override
   public Query getTermInSetQueryFromTextValues(List<String> textValues) {
-    List<Float> floatTerms = new ArrayList(textValues.size());
+    List<Float> floatTerms = new ArrayList<>(textValues.size());
     textValues.forEach((s) -> floatTerms.add(Float.parseFloat(s)));
     return FloatPoint.newSetQuery(getName(), floatTerms);
   }

src/main/java/com/yelp/nrtsearch/server/luceneserver/field/IdFieldDef.java

@@ -36,10 +36,10 @@
 import org.apache.lucene.util.BytesRef;
 
 /** Field class for defining '_ID' fields which are used to update documents */
-public class IdFieldDef extends IndexableFieldDef implements TermQueryable {
+public class IdFieldDef extends IndexableFieldDef<String> implements TermQueryable {
 
   protected IdFieldDef(String name, Field requestField) {
-    super(name, requestField);
+    super(name, requestField, String.class);
   }
 
   /**
@@ -119,7 +119,7 @@ public DocValuesType parseDocValuesType(Field requestField) {
    * @throws IOException
    */
   @Override
-  public LoadedDocValues<?> getDocValues(LeafReaderContext context) throws IOException {
+  public LoadedDocValues<String> getDocValues(LeafReaderContext context) throws IOException {
     if (hasDocValues()) {
       SortedDocValues sortedDocValues = DocValues.getSorted(context.reader(), getName());
       return new LoadedDocValues.SingleString(sortedDocValues);

src/main/java/com/yelp/nrtsearch/server/luceneserver/field/IndexableFieldDef.java

@@ -36,8 +36,12 @@
 import org.apache.lucene.index.LeafReaderContext;
 import org.apache.lucene.search.similarities.Similarity;
 
-/** Base class for all field definition types that can be written into the index. */
-public abstract class IndexableFieldDef extends FieldDef {
+/**
+ * Base class for all field definition types that can be written into the index.
+ *
+ * @param <T> doc value object type
+ */
+public abstract class IndexableFieldDef<T> extends FieldDef {
   public enum FacetValueType {
     NO_FACETS,
     FLAT,
@@ -52,8 +56,9 @@ public enum FacetValueType {
   private final PostingsFormat postingsFormat;
   private final DocValuesFormat docValuesFormat;
   private final Similarity similarity;
+  private final Class<? super T> docValuesObjectClass;
 
-  private final Map<String, IndexableFieldDef> childFields;
+  private final Map<String, IndexableFieldDef<?>> childFields;
 
   protected final DocValuesType docValuesType;
   protected final IndexableFieldDef.FacetValueType facetValueType;
@@ -68,8 +73,10 @@ public enum FacetValueType {
    *
    * @param name name of field
    * @param requestField field definition from grpc request
+   * @param docValuesObjectClass class of doc values object
    */
-  protected IndexableFieldDef(String name, Field requestField) {
+  protected IndexableFieldDef(
+      String name, Field requestField, Class<? super T> docValuesObjectClass) {
     super(name);
 
     validateRequest(requestField);
@@ -101,17 +108,19 @@ protected IndexableFieldDef(String name, Field requestField) {
     this.similarity =
         SimilarityCreator.getInstance().createSimilarity(similarityStr, similarityParams);
 
+    this.docValuesObjectClass = docValuesObjectClass;
+
     // add any children this field has
     if (requestField.getChildFieldsCount() > 0) {
-      Map<String, IndexableFieldDef> childFields = new HashMap<>();
+      Map<String, IndexableFieldDef<?>> childFields = new HashMap<>();
       for (Field field : requestField.getChildFieldsList()) {
         checkChildName(field.getName());
         String childName = getName() + IndexState.CHILD_FIELD_SEPARATOR + field.getName();
         FieldDef fieldDef = FieldDefCreator.getInstance().createFieldDef(childName, field);
         if (!(fieldDef instanceof IndexableFieldDef)) {
           throw new IllegalArgumentException("Child field is not indexable: " + childName);
         }
-        childFields.put(childName, (IndexableFieldDef) fieldDef);
+        childFields.put(childName, (IndexableFieldDef<?>) fieldDef);
       }
       this.childFields = Collections.unmodifiableMap(childFields);
     } else {
@@ -132,19 +141,19 @@ private void checkChildName(String name) {
   }
 
   /**
-   * Method called by {@link #IndexableFieldDef(String, Field)} to validate the provided {@link
-   * Field}. Field definitions should define a version that checks for incompatible parameters and
-   * any other potential issues. It is recommended to also call the super version of this method, so
-   * that general checks do not need to be repeated everywhere.
+   * Method called by {@link #IndexableFieldDef(String, Field, Class)} to validate the provided
+   * {@link Field}. Field definitions should define a version that checks for incompatible
+   * parameters and any other potential issues. It is recommended to also call the super version of
+   * this method, so that general checks do not need to be repeated everywhere.
    *
    * @param requestField field properties to validate
    */
   protected void validateRequest(Field requestField) {}
 
   /**
-   * Method called by {@link #IndexableFieldDef(String, Field)} to determine the doc value type used
-   * by this field. Fields are not necessarily limited to one doc value, but this should represent
-   * the primary value that will be accessible to scripts and search through {@link
+   * Method called by {@link #IndexableFieldDef(String, Field, Class)} to determine the doc value
+   * type used by this field. Fields are not necessarily limited to one doc value, but this should
+   * represent the primary value that will be accessible to scripts and search through {@link
    * #getDocValues(LeafReaderContext)}. A value of NONE implies that the field does not support doc
    * values.
    *
@@ -156,8 +165,8 @@ protected DocValuesType parseDocValuesType(Field requestField) {
   }
 
   /**
-   * Method called by {@link #IndexableFieldDef(String, Field)} to determine the facet value type
-   * for this field. The result of this method is exposed externally through {@link
+   * Method called by {@link #IndexableFieldDef(String, Field, Class)} to determine the facet value
+   * type for this field. The result of this method is exposed externally through {@link
    * #getFacetValueType()}. A value of NO_FACETS implies that the field does not support facets.
    *
    * @param requestField field from request
@@ -168,12 +177,12 @@ protected FacetValueType parseFacetValueType(Field requestField) {
   }
 
   /**
-   * Method called by {@link #IndexableFieldDef(String, Field)} to set the search properties on the
-   * given {@link FieldType}. The {@link FieldType#setStored(boolean)} has already been set to the
-   * value from {@link Field#getStore()}. This method should set any other needed properties, such
-   * as index options, tokenization, term vectors, etc. It likely should not set a doc value type,
-   * as those are usually added separately. The common use of this {@link FieldType} is to add a
-   * {@link FieldWithData} during indexing. This method should not freeze the field type.
+   * Method called by {@link #IndexableFieldDef(String, Field, Class)} to set the search properties
+   * on the given {@link FieldType}. The {@link FieldType#setStored(boolean)} has already been set
+   * to the value from {@link Field#getStore()}. This method should set any other needed properties,
+   * such as index options, tokenization, term vectors, etc. It likely should not set a doc value
+   * type, as those are usually added separately. The common use of this {@link FieldType} is to add
+   * a {@link FieldWithData} during indexing. This method should not freeze the field type.
    *
    * @param fieldType type that needs search properties set
    * @param requestField field from request
@@ -242,7 +251,7 @@ public boolean getEagerGlobalOrdinals() {
    *
    * @return child map
    */
-  public Map<String, IndexableFieldDef> getChildFields() {
+  public Map<String, IndexableFieldDef<?>> getChildFields() {
     return childFields;
   }
 
@@ -255,10 +264,19 @@ public Map<String, IndexableFieldDef> getChildFields() {
    * @return doc values for field
    * @throws IOException if there is an error loading doc values
    */
-  public LoadedDocValues<?> getDocValues(LeafReaderContext context) throws IOException {
+  public LoadedDocValues<? extends T> getDocValues(LeafReaderContext context) throws IOException {
     throw new UnsupportedOperationException("Doc values not supported for field: " + getName());
   }
 
+  /**
+   * Get the class of the doc values object for this field.
+   *
+   * @return class of doc values object
+   */
+  public Class<? super T> getDocValuesObjectClass() {
+    return docValuesObjectClass;
+  }
+
   /**
    * Transform a value from this fields index stored fields to a {@link
    * SearchResponse.Hit.FieldValue}. This will be called once for each value that was stored.