Placeholder.java

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// to you under the Apache License, Version 2.0 (the
// "License"); you may not use this file except in compliance
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//
//   http://www.apache.org/licenses/LICENSE-2.0
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package org.apache.doris.nereids.trees.expressions;

import org.apache.doris.analysis.PlaceHolderExpr;
import org.apache.doris.catalog.MysqlColType;
import org.apache.doris.nereids.exceptions.UnboundException;
import org.apache.doris.nereids.trees.expressions.shape.LeafExpression;
import org.apache.doris.nereids.trees.expressions.visitor.ExpressionVisitor;
import org.apache.doris.nereids.trees.plans.PlaceholderId;
import org.apache.doris.nereids.types.DataType;
import org.apache.doris.nereids.types.NullType;

import java.util.Optional;

/**
 * Placeholder for prepared statement
 */
public class Placeholder extends Expression implements LeafExpression {
    private final PlaceholderId placeholderId;
    private final Optional<MysqlColType> mysqlColType;
    private int mysqlTypeCode = -1;

    public Placeholder(PlaceholderId placeholderId) {
        this.placeholderId = placeholderId;
        this.mysqlColType = Optional.empty();
    }

    public Placeholder(PlaceholderId placeholderId, int mysqlTypeCode) {
        this.placeholderId = placeholderId;
        this.mysqlColType = Optional.of(MysqlColType.fromCode(mysqlTypeCode));
        this.mysqlTypeCode = mysqlTypeCode;
    }

    public PlaceholderId getPlaceholderId() {
        return placeholderId;
    }

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

    @Override
    public boolean nullable() {
        return true;
    }

    @Override
    public String toString() {
        return "$" + placeholderId.asInt();
    }

    @Override
    public String computeToSql() {
        return "?";
    }

    @Override
    public int fastChildrenHashCode() {
        return placeholderId.asInt();
    }

    @Override
    public DataType getDataType() throws UnboundException {
        return NullType.INSTANCE;
    }

    public Placeholder withNewMysqlColType(int mysqlTypeCode) {
        return new Placeholder(getPlaceholderId(), mysqlTypeCode);
    }

    public boolean isUnsigned() {
        return MysqlColType.isUnsigned(mysqlTypeCode);
    }

    public MysqlColType getMysqlColType() {
        return mysqlColType.get();
    }

    @Override
    public boolean equals(Object o) {
        if (!(o instanceof PlaceHolderExpr)) {
            return false;
        }
        Placeholder other = (Placeholder) o;
        return placeholderId == other.placeholderId;
    }
}