Update Javadoc for Projections. (#1216)

Author: vbabanin

driver-core/src/main/com/mongodb/client/model/FindOneAndDeleteOptions.java

@@ -59,6 +59,7 @@ public Bson getProjection() {
      * @param projection the project document, which may be null.
      * @return this
      * @mongodb.driver.manual tutorial/project-fields-from-query-results Projection
+     * @see Projections
      */
     public FindOneAndDeleteOptions projection(@Nullable final Bson projection) {
         this.projection = projection;

driver-core/src/main/com/mongodb/client/model/FindOneAndReplaceOptions.java

@@ -62,6 +62,7 @@ public Bson getProjection() {
      * @param projection the project document, which may be null.
      * @return this
      * @mongodb.driver.manual tutorial/project-fields-from-query-results Projection
+     * @see Projections
      */
     public FindOneAndReplaceOptions projection(@Nullable final Bson projection) {
         this.projection = projection;

driver-core/src/main/com/mongodb/client/model/FindOneAndUpdateOptions.java

@@ -64,6 +64,7 @@ public Bson getProjection() {
      * @param projection the project document, which may be null.
      * @return this
      * @mongodb.driver.manual tutorial/project-fields-from-query-results Projection
+     * @see Projections
      */
     public FindOneAndUpdateOptions projection(@Nullable final Bson projection) {
         this.projection = projection;

driver-core/src/main/com/mongodb/client/model/Projections.java

@@ -52,8 +52,20 @@ private Projections() {
     }
 
     /**
-     * Creates a projection of a field whose value is computed from the given expression.  Projection with an expression is only supported
-     * using the $project aggregation pipeline stage.
+     * Creates a projection of a field whose value is computed from the given expression. Projection with an expression can be used in the
+     * following contexts:
+     * <ul>
+     *   <li>$project aggregation pipeline stage.</li>
+     *   <li>Starting from MongoDB 4.4, it's also accepted in various find-related methods within the
+     *   {@code MongoCollection}-based API where projection is supported, for example:
+     *     <ul>
+     *       <li>{@code find()}</li>
+     *       <li>{@code findOneAndReplace()}</li>
+     *       <li>{@code findOneAndUpdate()}</li>
+     *       <li>{@code findOneAndDelete()}</li>
+     *     </ul>
+     *   </li>
+     * </ul>
      *
      * @param fieldName     the field name
      * @param expression    the expression

driver-reactive-streams/src/main/com/mongodb/reactivestreams/client/FindPublisher.java

@@ -19,6 +19,7 @@
 import com.mongodb.CursorType;
 import com.mongodb.ExplainVerbosity;
 import com.mongodb.client.model.Collation;
+import com.mongodb.client.model.Projections;
 import com.mongodb.lang.Nullable;
 import org.bson.BsonValue;
 import org.bson.Document;
@@ -104,6 +105,7 @@ public interface FindPublisher<TResult> extends Publisher<TResult> {
      * @param projection the project document, which may be null.
      * @return this
      * @mongodb.driver.manual reference/method/db.collection.find/ Projection
+     * @see Projections
      */
     FindPublisher<TResult> projection(@Nullable Bson projection);
     /**

driver-scala/src/main/scala/org/mongodb/scala/FindObservable.scala

@@ -121,6 +121,7 @@ case class FindObservable[TResult](private val wrapped: FindPublisher[TResult])
    * [[https://www.mongodb.com/docs/manual/reference/method/db.collection.find/ Projection]]
    * @param projection the project document, which may be null.
    * @return this
+   * @see [[org.mongodb.scala.model.Projections]]
    */
   def projection(projection: Bson): FindObservable[TResult] = {
     wrapped.projection(projection)

driver-scala/src/main/scala/org/mongodb/scala/model/Projections.scala

@@ -32,8 +32,20 @@ import org.mongodb.scala.bson.conversions.Bson
 object Projections {
 
   /**
-   * Creates a projection of a field whose value is computed from the given expression.  Projection with an expression is only supported
-   * using the `\$project` aggregation pipeline stage.
+   * Creates a projection of a field whose value is computed from the given expression. Projection with an expression can be used in the
+   * following contexts:
+   * <ul>
+   *    <li>$project aggregation pipeline stage.</li>
+   *    <li>Starting from MongoDB 4.4, it's also accepted in various find-related methods within the
+   * `MongoCollection`-based API where projection is supported, for example:
+   *        <ul>
+   *          <li>`find()`</li>
+   *          <li>`findOneAndReplace()`</li>
+   *          <li>`findOneAndUpdate()`</li>
+   *          <li>`findOneAndDelete()`</li>
+   *        </ul>
+   *    </li>
+   * </ul>
    *
    * @param fieldName     the field name
    * @param  expression   the expression

driver-sync/src/main/com/mongodb/client/FindIterable.java

@@ -19,6 +19,7 @@
 import com.mongodb.CursorType;
 import com.mongodb.ExplainVerbosity;
 import com.mongodb.client.model.Collation;
+import com.mongodb.client.model.Projections;
 import com.mongodb.lang.Nullable;
 import org.bson.BsonValue;
 import org.bson.Document;
@@ -96,6 +97,7 @@ public interface FindIterable<TResult> extends MongoIterable<TResult> {
      * @param projection the project document, which may be null.
      * @return this
      * @mongodb.driver.manual reference/method/db.collection.find/ Projection
+     * @see Projections
      */
     FindIterable<TResult> projection(@Nullable Bson projection);