[Javadocs] add to o.o.dfs,fetch,internal,lookup,profile, and query pa…

…ckages (#3261)

Adds class level javadocs to org.opensearch.dfs, fetch, internal, lookup,
profile, and query packages.

Signed-off-by: Nicholas Walter Knize <nknize@apache.org>

server/src/main/java/org/opensearch/search/dfs/AggregatedDfs.java

@@ -44,6 +44,11 @@
 
 import java.io.IOException;
 
+/**
+ * Compute global distributed frequency across the index
+ *
+ * @opensearch.internal
+ */
 public class AggregatedDfs implements Writeable {
 
     private ObjectObjectHashMap<Term, TermStatistics> termStatistics;

server/src/main/java/org/opensearch/search/dfs/DfsPhase.java

@@ -51,6 +51,8 @@
 /**
  * Dfs phase of a search request, used to make scoring 100% accurate by collecting additional info from each shard before the query phase.
  * The additional information is used to better compare the scores coming from all the shards, which depend on local factors (e.g. idf)
+ *
+ * @opensearch.internal
  */
 public class DfsPhase {
 

server/src/main/java/org/opensearch/search/dfs/DfsPhaseExecutionException.java

@@ -38,6 +38,11 @@
 
 import java.io.IOException;
 
+/**
+ * Thrown if there are any errors in the DFS phase
+ *
+ * @opensearch.internal
+ */
 public class DfsPhaseExecutionException extends SearchException {
 
     public DfsPhaseExecutionException(SearchShardTarget shardTarget, String msg, Throwable t) {

server/src/main/java/org/opensearch/search/dfs/DfsSearchResult.java

@@ -49,6 +49,11 @@
 
 import java.io.IOException;
 
+/**
+ * Result from a Distributed Frequency Search phase
+ *
+ * @opensearch.internal
+ */
 public class DfsSearchResult extends SearchPhaseResult {
 
     private static final Term[] EMPTY_TERMS = new Term[0];

server/src/main/java/org/opensearch/search/fetch/FetchContext.java

@@ -57,6 +57,8 @@
 
 /**
  * Encapsulates state required to execute fetch phases
+ *
+ * @opensearch.internal
  */
 public class FetchContext {
 

server/src/main/java/org/opensearch/search/fetch/FetchPhase.java

@@ -90,6 +90,8 @@
 /**
  * Fetch phase of a search request, used to fetch the actual top matching documents to be returned to the client, identified
  * after reducing all of the matches returned by the query phase
+ *
+ * @opensearch.internal
  */
 public class FetchPhase {
     private static final Logger LOGGER = LogManager.getLogger(FetchPhase.class);

server/src/main/java/org/opensearch/search/fetch/FetchPhaseExecutionException.java

@@ -38,6 +38,11 @@
 
 import java.io.IOException;
 
+/**
+ * Thrown when there are errors during the fetch phase
+ *
+ * @opensearch.internal
+ */
 public class FetchPhaseExecutionException extends SearchException {
 
     public FetchPhaseExecutionException(SearchShardTarget shardTarget, String msg, Throwable t) {

server/src/main/java/org/opensearch/search/fetch/FetchSearchResult.java

@@ -43,6 +43,11 @@
 
 import java.io.IOException;
 
+/**
+ * Result from a fetch
+ *
+ * @opensearch.internal
+ */
 public final class FetchSearchResult extends SearchPhaseResult {
 
     private SearchHits hits;

server/src/main/java/org/opensearch/search/fetch/FetchSubPhase.java

@@ -42,6 +42,8 @@
 
 /**
  * Sub phase within the fetch phase used to fetch things *about* the documents like highlighting or matched queries.
+ *
+ * @opensearch.internal
  */
 public interface FetchSubPhase {
 

server/src/main/java/org/opensearch/search/fetch/FetchSubPhaseProcessor.java

@@ -39,6 +39,8 @@
 
 /**
  * Executes the logic for a {@link FetchSubPhase} against a particular leaf reader and hit
+ *
+ * @opensearch.internal
  */
 public interface FetchSubPhaseProcessor {
 

server/src/main/java/org/opensearch/search/fetch/QueryFetchSearchResult.java

@@ -41,6 +41,11 @@
 
 import java.io.IOException;
 
+/**
+ * Query fetch result
+ *
+ * @opensearch.internal
+ */
 public final class QueryFetchSearchResult extends SearchPhaseResult {
 
     private final QuerySearchResult queryResult;

server/src/main/java/org/opensearch/search/fetch/ScrollQueryFetchSearchResult.java

@@ -40,6 +40,11 @@
 
 import java.io.IOException;
 
+/**
+ * Scroll fetch result
+ *
+ * @opensearch.internal
+ */
 public final class ScrollQueryFetchSearchResult extends SearchPhaseResult {
 
     private final QueryFetchSearchResult result;

server/src/main/java/org/opensearch/search/fetch/ShardFetchRequest.java

@@ -54,6 +54,8 @@
 /**
  * Shard level fetch base request. Holds all the info needed to execute a fetch.
  * Used with search scroll as the original request doesn't hold indices.
+ *
+ * @opensearch.internal
  */
 public class ShardFetchRequest extends TransportRequest {
 

server/src/main/java/org/opensearch/search/fetch/ShardFetchSearchRequest.java

@@ -50,6 +50,8 @@
 /**
  * Shard level fetch request used with search. Holds indices taken from the original search request
  * and implements {@link org.opensearch.action.IndicesRequest}.
+ *
+ * @opensearch.internal
  */
 public class ShardFetchSearchRequest extends ShardFetchRequest implements IndicesRequest {
 

server/src/main/java/org/opensearch/search/fetch/StoredFieldsContext.java

@@ -50,6 +50,8 @@
 
 /**
  * Context used to fetch the {@code stored_fields}.
+ *
+ * @opensearch.internal
  */
 public class StoredFieldsContext implements Writeable {
     public static final String _NONE_ = "_none_";

server/src/main/java/org/opensearch/search/fetch/subphase/ExplainPhase.java

@@ -42,6 +42,8 @@
 
 /**
  * Explains the scoring calculations for the top hits.
+ *
+ * @opensearch.internal
  */
 public final class ExplainPhase implements FetchSubPhase {
 

server/src/main/java/org/opensearch/search/fetch/subphase/FetchDocValuesContext.java

@@ -41,6 +41,8 @@
 
 /**
  * All the required context to pull a field from the doc values.
+ *
+ * @opensearch.internal
  */
 public class FetchDocValuesContext {
     private final List<FieldAndFormat> fields;

server/src/main/java/org/opensearch/search/fetch/subphase/FetchDocValuesPhase.java

@@ -49,6 +49,8 @@
  * Fetch sub phase which pulls data from doc values.
  *
  * Specifying {@code "docvalue_fields": ["field1", "field2"]}
+ *
+ * @opensearch.internal
  */
 public final class FetchDocValuesPhase implements FetchSubPhase {
 

server/src/main/java/org/opensearch/search/fetch/subphase/FetchFieldsContext.java

@@ -35,6 +35,8 @@
 
 /**
  * The context needed to retrieve fields.
+ *
+ * @opensearch.internal
  */
 public class FetchFieldsContext {
     private final List<FieldAndFormat> fields;

server/src/main/java/org/opensearch/search/fetch/subphase/FetchFieldsPhase.java

@@ -50,6 +50,8 @@
 /**
  * A fetch sub-phase for high-level field retrieval. Given a list of fields, it
  * retrieves the field values from _source and returns them as document fields.
+ *
+ * @opensearch.internal
  */
 public final class FetchFieldsPhase implements FetchSubPhase {
 

server/src/main/java/org/opensearch/search/fetch/subphase/FetchScorePhase.java

@@ -44,6 +44,11 @@
 
 import java.io.IOException;
 
+/**
+ * Fetches the score of a query match during search phase
+ *
+ * @opensearch.internal
+ */
 public class FetchScorePhase implements FetchSubPhase {
 
     @Override

server/src/main/java/org/opensearch/search/fetch/subphase/FetchSourceContext.java

@@ -54,6 +54,8 @@
 
 /**
  * Context used to fetch the {@code _source}.
+ *
+ * @opensearch.internal
  */
 public class FetchSourceContext implements Writeable, ToXContentObject {
 

server/src/main/java/org/opensearch/search/fetch/subphase/FetchSourcePhase.java

@@ -46,6 +46,11 @@
 import java.io.IOException;
 import java.util.Map;
 
+/**
+ * Fetches the document source during search phase
+ *
+ * @opensearch.internal
+ */
 public final class FetchSourcePhase implements FetchSubPhase {
 
     @Override

server/src/main/java/org/opensearch/search/fetch/subphase/FetchVersionPhase.java

@@ -41,6 +41,11 @@
 
 import java.io.IOException;
 
+/**
+ * Fetches the version of a term during search phase
+ *
+ * @opensearch.internal
+ */
 public final class FetchVersionPhase implements FetchSubPhase {
 
     @Override

server/src/main/java/org/opensearch/search/fetch/subphase/FieldAndFormat.java

@@ -49,6 +49,8 @@
 /**
  * Wrapper around a field name and the format that should be used to
  * display values of this field.
+ *
+ * @opensearch.internal
  */
 public final class FieldAndFormat implements Writeable, ToXContentObject {
     private static final ParseField FIELD_FIELD = new ParseField("field");

server/src/main/java/org/opensearch/search/fetch/subphase/FieldFetcher.java

@@ -51,6 +51,8 @@
 /**
  * A helper class to {@link FetchFieldsPhase} that's initialized with a list of field patterns to fetch.
  * Then given a specific document, it can retrieve the corresponding fields from the document's source.
+ *
+ * @opensearch.internal
  */
 public class FieldFetcher {
     public static FieldFetcher create(QueryShardContext context, SearchLookup searchLookup, Collection<FieldAndFormat> fieldAndFormats) {

server/src/main/java/org/opensearch/search/fetch/subphase/InnerHitsContext.java

@@ -58,6 +58,8 @@
 
 /**
  * Context used for inner hits retrieval
+ *
+ * @opensearch.internal
  */
 public final class InnerHitsContext {
     private final Map<String, InnerHitSubContext> innerHits;

server/src/main/java/org/opensearch/search/fetch/subphase/InnerHitsPhase.java

@@ -49,6 +49,11 @@
 import java.util.HashMap;
 import java.util.Map;
 
+/**
+ * Gets the inner hits of a document during search
+ *
+ * @opensearch.internal
+ */
 public final class InnerHitsPhase implements FetchSubPhase {
 
     private final FetchPhase fetchPhase;

server/src/main/java/org/opensearch/search/fetch/subphase/MatchedQueriesPhase.java

@@ -48,6 +48,11 @@
 import java.util.List;
 import java.util.Map;
 
+/**
+ * Fetches queries that match the document during search phase
+ *
+ * @opensearch.internal
+ */
 public final class MatchedQueriesPhase implements FetchSubPhase {
 
     @Override

server/src/main/java/org/opensearch/search/fetch/subphase/ScriptFieldsContext.java

@@ -37,6 +37,11 @@
 import java.util.ArrayList;
 import java.util.List;
 
+/**
+ * Context used for script fields
+ *
+ * @opensearch.internal
+ */
 public class ScriptFieldsContext {
 
     public static class ScriptField {

server/src/main/java/org/opensearch/search/fetch/subphase/ScriptFieldsPhase.java

@@ -45,6 +45,11 @@
 import java.util.Collections;
 import java.util.List;
 
+/**
+ * Gets the scripted fields during search phase
+ *
+ * @opensearch.internal
+ */
 public final class ScriptFieldsPhase implements FetchSubPhase {
 
     @Override

server/src/main/java/org/opensearch/search/fetch/subphase/SeqNoPrimaryTermPhase.java

@@ -41,6 +41,11 @@
 
 import java.io.IOException;
 
+/**
+ * Fetches the sequence number of the primary term during search phase
+ *
+ * @opensearch.internal
+ */
 public final class SeqNoPrimaryTermPhase implements FetchSubPhase {
 
     @Override

server/src/main/java/org/opensearch/search/fetch/subphase/highlight/AbstractHighlighterBuilder.java

@@ -62,6 +62,8 @@
 /**
  * This abstract class holds parameters shared by {@link HighlightBuilder} and {@link HighlightBuilder.Field}
  * and provides the common setters, equality, hashCode calculation and common serialization
+ *
+ * @opensearch.internal
  */
 public abstract class AbstractHighlighterBuilder<HB extends AbstractHighlighterBuilder<?>>
     implements

server/src/main/java/org/opensearch/search/fetch/subphase/highlight/CustomQueryScorer.java

@@ -43,6 +43,11 @@
 import java.io.IOException;
 import java.util.Map;
 
+/**
+ * Internally used for custom scoring
+ *
+ * @opensearch.internal
+ */
 public final class CustomQueryScorer extends QueryScorer {
 
     public CustomQueryScorer(Query query, IndexReader reader, String field, String defaultField) {

server/src/main/java/org/opensearch/search/fetch/subphase/highlight/FastVectorHighlighter.java

@@ -64,6 +64,11 @@
 import java.util.Map;
 import java.util.function.Function;
 
+/**
+ * Uses Lucene's Fast Vector Highlighting
+ *
+ * @opensearch.internal
+ */
 public class FastVectorHighlighter implements Highlighter {
     private static final BoundaryScanner DEFAULT_SIMPLE_BOUNDARY_SCANNER = new SimpleBoundaryScanner();
     private static final BoundaryScanner DEFAULT_SENTENCE_BOUNDARY_SCANNER = new BreakIteratorBoundaryScanner(

server/src/main/java/org/opensearch/search/fetch/subphase/highlight/FieldHighlightContext.java

@@ -38,6 +38,11 @@
 
 import java.util.Map;
 
+/**
+ * Context used during field level highlighting
+ *
+ * @opensearch.internal
+ */
 public class FieldHighlightContext {
 
     public final String fieldName;

server/src/main/java/org/opensearch/search/fetch/subphase/highlight/FragmentBuilderHelper.java

@@ -49,6 +49,8 @@
 
 /**
  * Simple helper class for {@link FastVectorHighlighter} {@link FragmentsBuilder} implementations.
+ *
+ * @opensearch.internal
  */
 public final class FragmentBuilderHelper {
 

server/src/main/java/org/opensearch/search/fetch/subphase/highlight/HighlightBuilder.java

@@ -67,6 +67,8 @@
  * are summarized to show only selected snippets ("fragments") containing search terms.
  *
  * @see org.opensearch.search.builder.SearchSourceBuilder#highlight()
+ *
+ * @opensearch.internal
  */
 public class HighlightBuilder extends AbstractHighlighterBuilder<HighlightBuilder> {
     /** default for whether to highlight fields based on the source even if stored separately */