HHH-15352 add ScrollableResults.setFetchSize()

hibernate-core/src/main/java/org/hibernate/ScrollableResults.java

@@ -135,4 +135,16 @@ public interface ScrollableResults<R> extends AutoCloseable, Closeable {
 	 * @return true if there is a row at that row number
 	 */
 	boolean setRowNumber(int rowNumber);
+
+	/**
+	 * Gives the JDBC driver a hint as to the number of rows that
+	 * should be fetched from the database when more rows are needed.
+	 * If {@code 0}, the JDBC driver's default setting will be used.
+	 *
+	 * @see java.sql.ResultSet#setFetchSize(int)
+	 * @see org.hibernate.cfg.AvailableSettings#STATEMENT_FETCH_SIZE
+	 *
+	 * @since 6.1.1
+	 */
+	void setFetchSize(int fetchSize);
 }

hibernate-core/src/main/java/org/hibernate/cfg/AvailableSettings.java

@@ -945,8 +945,9 @@ public interface AvailableSettings {
 	 * from the database when more rows are needed. If {@code 0}, the JDBC driver's
 	 * default settings will be used.
 	 *
-	 * @see java.sql.ResultSet#setFetchSize(int)
+	 * @see java.sql.PreparedStatement#setFetchSize(int)
 	 * @see org.hibernate.boot.SessionFactoryBuilder#applyJdbcFetchSize(int)
+	 * @see org.hibernate.ScrollableResults#setFetchSize(int)
 	 */
 	String STATEMENT_FETCH_SIZE = "hibernate.jdbc.fetch_size";
 

hibernate-core/src/main/java/org/hibernate/internal/AbstractScrollableResults.java

@@ -85,6 +85,11 @@ public abstract class AbstractScrollableResults<R> implements ScrollableResultsI
 		getPersistenceContext().afterScrollOperation();
 	}
 
+	@Override
+	public void setFetchSize(int fetchSize) {
+		getJdbcValues().setFetchSize(fetchSize);
+	}
+
 	@Override
 	public final void close() {
 		if ( this.closed ) {

hibernate-core/src/main/java/org/hibernate/internal/EmptyScrollableResults.java

@@ -91,6 +91,9 @@ public class EmptyScrollableResults implements ScrollableResultsImplementor {
 		return false;
 	}
 
+	@Override
+	public void setFetchSize(int fetchSize) {}
+
 	@Override
 	public Object[] get() {
 		return ArrayHelper.EMPTY_OBJECT_ARRAY;

hibernate-core/src/main/java/org/hibernate/sql/results/jdbc/internal/JdbcValuesCacheHit.java

@@ -227,4 +227,7 @@ public class JdbcValuesCacheHit extends AbstractJdbcValues {
 	protected void release() {
 		cachedData = null;
 	}
+
+	@Override
+	public void setFetchSize(int fetchSize) {}
 }

hibernate-core/src/main/java/org/hibernate/sql/results/jdbc/internal/JdbcValuesResultSetImpl.java

@@ -324,4 +324,14 @@ public class JdbcValuesResultSetImpl extends AbstractJdbcValues {
 	public Object[] getCurrentRowValuesArray() {
 		return currentRowJdbcValues;
 	}
+
+	@Override
+	public void setFetchSize(int fetchSize) {
+		try {
+			resultSetAccess.getResultSet().setFetchSize(fetchSize);
+		}
+		catch (SQLException e) {
+			throw makeExecutionException( "Error calling ResultSet.setFetchSize()", e );
+		}
+	}
 }

hibernate-core/src/main/java/org/hibernate/sql/results/jdbc/spi/JdbcValues.java

@@ -78,4 +78,6 @@ public interface JdbcValues {
 	 * Give implementations a chance to finish processing
 	 */
 	void finishUp(SharedSessionContractImplementor session);
+
+	void setFetchSize(int fetchSize);
 }