StatisticsBuilder.java

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// distributed with this work for additional information
// regarding copyright ownership.  The ASF licenses this file
// to you 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
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// specific language governing permissions and limitations
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package org.apache.doris.statistics;

import org.apache.doris.nereids.trees.expressions.Expression;

import java.util.HashMap;
import java.util.Map;
import java.util.Set;

public class StatisticsBuilder {

    private double rowCount;
    private int widthInJoinCluster = 1;
    private final Map<Expression, ColumnStatistic> expressionToColumnStats;

    private double deltaRowCount = 0.0;

    private boolean isFromHbo = false;

    public StatisticsBuilder() {
        this.expressionToColumnStats = new HashMap<>();
    }

    public StatisticsBuilder(Statistics statistics) {
        this.rowCount = statistics.getRowCount();
        this.widthInJoinCluster = statistics.getWidthInJoinCluster();
        this.deltaRowCount = statistics.getDeltaRowCount();
        this.expressionToColumnStats = new HashMap<>();
        this.expressionToColumnStats.putAll(statistics.columnStatistics());
        this.isFromHbo = statistics.isFromHbo();
    }

    public StatisticsBuilder setRowCount(double rowCount) {
        this.rowCount = rowCount;
        return this;
    }

    public StatisticsBuilder setWidthInJoinCluster(int widthInJoinCluster) {
        this.widthInJoinCluster = widthInJoinCluster;
        return this;
    }

    public StatisticsBuilder setDeltaRowCount(double deltaRowCount) {
        this.deltaRowCount = deltaRowCount;
        return this;
    }

    public StatisticsBuilder putColumnStatistics(
            Map<Expression, ColumnStatistic> expressionToColumnStats) {
        this.expressionToColumnStats.putAll(expressionToColumnStats);
        return this;
    }

    public StatisticsBuilder putColumnStatistics(Expression expression, ColumnStatistic columnStatistic) {
        expressionToColumnStats.put(expression, columnStatistic);
        return this;
    }

    public Set<Map.Entry<Expression, ColumnStatistic>> getExpressionColumnStatsEntries() {
        return expressionToColumnStats.entrySet();
    }

    public Statistics build() {
        return new Statistics(rowCount, widthInJoinCluster, expressionToColumnStats, deltaRowCount, isFromHbo);
    }
}