ScanContext.java

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// to you under the Apache License, Version 2.0 (the
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//
//   http://www.apache.org/licenses/LICENSE-2.0
//
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package org.apache.doris.planner;

/**
 * Shared context for scan planning/runtime decisions.
 * <p>
 * Keep this object immutable so scan nodes can safely cache it and
 * we can evolve fields incrementally in future.
 */
public final class ScanContext {
    public static final ScanContext EMPTY = new ScanContext("");

    private final String clusterName;

    private ScanContext(String clusterName) {
        this.clusterName = clusterName == null ? "" : clusterName;
    }

    public static Builder builder() {
        return new Builder();
    }

    public String getClusterName() {
        return clusterName;
    }

    public static final class Builder {
        private String clusterName = "";

        public Builder clusterName(String clusterName) {
            this.clusterName = clusterName;
            return this;
        }

        public ScanContext build() {
            if (clusterName == null || clusterName.isEmpty()) {
                return ScanContext.EMPTY;
            }
            return new ScanContext(clusterName);
        }
    }
}