JsonArray.java

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

import org.apache.doris.catalog.FunctionSignature;
import org.apache.doris.nereids.trees.expressions.Expression;
import org.apache.doris.nereids.trees.expressions.functions.AlwaysNotNullable;
import org.apache.doris.nereids.trees.expressions.functions.CustomSignature;
import org.apache.doris.nereids.trees.expressions.visitor.ExpressionVisitor;
import org.apache.doris.nereids.types.DataType;
import org.apache.doris.nereids.types.JsonType;
import org.apache.doris.nereids.types.VarcharType;
import org.apache.doris.nereids.util.ExpressionUtils;

import java.util.ArrayList;
import java.util.List;

/**
 * ScalarFunction 'json_array'. This class is generated by GenerateFunction.
 */
public class JsonArray extends ScalarFunction implements CustomSignature, AlwaysNotNullable {

    /**
     * constructor with 0 or more arguments.
     */
    public JsonArray(Expression... varArgs) {
        super("json_array", ExpressionUtils.mergeArguments(varArgs));
    }

    @Override
    public FunctionSignature customSignature() {
        List<DataType> arguments = new ArrayList<>();
        for (int i = 0; i < arity(); i++) {
            if (getArgumentType(i).isComplexType() || getArgumentType(i).isJsonType()) {
                // keep origin type for BE Serialization
                arguments.add(JsonType.INSTANCE);
            } else {
                arguments.add(VarcharType.SYSTEM_DEFAULT);
            }
        }
        return FunctionSignature.of(VarcharType.SYSTEM_DEFAULT, arguments);
    }

    /**
     * withChildren.
     */
    @Override
    public JsonArray withChildren(List<Expression> children) {
        return new JsonArray(children.toArray(new Expression[0]));
    }

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