ConnectorMvccSnapshotAdapter.java

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package org.apache.doris.connector;

import org.apache.doris.connector.api.mvcc.ConnectorMvccSnapshot;
import org.apache.doris.datasource.mvcc.MvccSnapshot;

import java.util.Objects;

/**
 * Adapter that lets a connector-provided {@link ConnectorMvccSnapshot} flow through the
 * engine's existing {@link MvccSnapshot} contract (consumed by the nereids analyzer and
 * the scan plan). Constructed when {@code ConnectorMetadata.beginQuerySnapshot} returns
 * a value; passed unchanged through fe-core MVCC pinning, then unwrapped on the BE
 * serialization boundary via {@link #getSnapshot()}.
 */
public final class ConnectorMvccSnapshotAdapter implements MvccSnapshot {

    private final ConnectorMvccSnapshot snapshot;

    public ConnectorMvccSnapshotAdapter(ConnectorMvccSnapshot snapshot) {
        this.snapshot = Objects.requireNonNull(snapshot, "snapshot");
    }

    public ConnectorMvccSnapshot getSnapshot() {
        return snapshot;
    }
}