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This is a Databricks build of Trino's Hive plugin which includes support for HTTP based transport for it's Hive metastore thrift interface.

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/*
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package io.trino.plugin.hive;

import io.trino.spi.connector.ConnectorPageSource;

import java.util.Optional;

import static java.util.Objects.requireNonNull;

/**
 * A wrapper class for
 * 
 *  delegate reader page source and
 * 
 columns to be read by the delegate (present only if different from the columns desired by the connector pagesource)
 * 
 */
public class ReaderPageSource
{
    private final ConnectorPageSource connectorPageSource;
    private final Optional columns;

    public ReaderPageSource(ConnectorPageSource connectorPageSource, Optional columns)
    {
        this.connectorPageSource = requireNonNull(connectorPageSource, "connectorPageSource is null");
        this.columns = requireNonNull(columns, "columns is null");
    }

    public ConnectorPageSource get()
    {
        return connectorPageSource;
    }

    public Optional getReaderColumns()
    {
        return columns;
    }

    public static ReaderPageSource noProjectionAdaptation(ConnectorPageSource connectorPageSource)
    {
        return new ReaderPageSource(connectorPageSource, Optional.empty());
    }
}