PlanningSplitMetadata.java

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package org.apache.doris.datasource;

/**
 * Read-only metadata published by a {@link PlanningSplitProducer}.
 *
 * <p>This interface is intentionally marker-like. Datasource-specific producers can extend it with
 * richer typed accessors without forcing generic planning code to depend on datasource internals.
 */
public interface PlanningSplitMetadata {
    /**
     * Empty metadata object used by producers that do not publish extra planning state.
     */
    PlanningSplitMetadata EMPTY = new PlanningSplitMetadata() {
    };
}