EqualTo.java

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package org.apache.doris.nereids.trees.expressions;

import org.apache.doris.nereids.exceptions.UnboundException;
import org.apache.doris.nereids.trees.expressions.functions.PropagateNullable;
import org.apache.doris.nereids.trees.expressions.visitor.ExpressionVisitor;

import com.google.common.base.Preconditions;
import com.google.common.collect.ImmutableList;

import java.util.List;

/**
 * Equal to expression: a = b.
 */
public class EqualTo extends EqualPredicate implements PropagateNullable {

    public EqualTo(Expression left, Expression right) {
        this(left, right, false);
    }

    public EqualTo(Expression left, Expression right, boolean inferred) {
        super(ImmutableList.of(left, right), "=", inferred);
    }

    private EqualTo(List<Expression> children, boolean inferred) {
        super(children, "=", inferred);
    }

    @Override
    public boolean nullable() throws UnboundException {
        return left().nullable() || right().nullable();
    }

    @Override
    public EqualTo withChildren(List<Expression> children) {
        Preconditions.checkArgument(children.size() == 2);
        return new EqualTo(children, this.isInferred());
    }

    @Override
    public Expression withInferred(boolean inferred) {
        return new EqualTo(this.children, inferred);
    }

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

    @Override
    public EqualTo commute() {
        return new EqualTo(right(), left());
    }
}