UnboundStar.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.nereids.analyzer;

import org.apache.doris.common.Pair;
import org.apache.doris.nereids.exceptions.UnboundException;
import org.apache.doris.nereids.trees.expressions.NamedExpression;
import org.apache.doris.nereids.trees.expressions.functions.PropagateNullable;
import org.apache.doris.nereids.trees.expressions.shape.LeafExpression;
import org.apache.doris.nereids.trees.expressions.visitor.ExpressionVisitor;
import org.apache.doris.nereids.util.Utils;

import com.google.common.collect.ImmutableList;

import java.util.List;
import java.util.Objects;
import java.util.Optional;

/**
 * Star expression.
 */
public class UnboundStar extends NamedExpression implements LeafExpression, Unbound, PropagateNullable {
    private final List<String> qualifier;
    // the start and end position of the sql substring(e.g. "*", "table.*")
    private final Optional<Pair<Integer, Integer>> indexInSqlString;

    public UnboundStar(List<String> qualifier) {
        super(ImmutableList.of());
        this.qualifier = Objects.requireNonNull(ImmutableList.copyOf(qualifier), "qualifier can not be null");
        this.indexInSqlString = Optional.empty();
    }

    public UnboundStar(List<String> qualifier, Optional<Pair<Integer, Integer>> indexInSqlString) {
        super(ImmutableList.of());
        this.qualifier = Objects.requireNonNull(ImmutableList.copyOf(qualifier), "qualifier can not be null");
        this.indexInSqlString = indexInSqlString;
    }

    @Override
    public String computeToSql() {
        return Utils.qualifiedName(qualifier, "*");
    }

    @Override
    public List<String> getQualifier() throws UnboundException {
        return qualifier;
    }

    @Override
    public String toString() {
        return toSql();
    }

    @Override
    public boolean equals(Object o) {
        if (this == o) {
            return true;
        }
        if (o == null || getClass() != o.getClass()) {
            return false;
        }
        if (!super.equals(o)) {
            return false;
        }
        UnboundStar that = (UnboundStar) o;
        return qualifier.equals(that.qualifier);
    }

    public Optional<Pair<Integer, Integer>> getIndexInSqlString() {
        return indexInSqlString;
    }

    @Override
    public int computeHashCode() {
        return Objects.hash(super.computeHashCode(), qualifier);
    }

    @Override
    public <R, C> R accept(ExpressionVisitor<R, C> visitor, C context) {
        return visitor.visitUnboundStar(this, context);
    }

    public UnboundStar withIndexInSql(Pair<Integer, Integer> index) {
        return new UnboundStar(qualifier, Optional.ofNullable(index));
    }
}