regression-test/java-udf-src/src/main/java/org/apache/doris/udf/DateCaseTest.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.udf;

import org.apache.hadoop.hive.ql.exec.UDF;
import java.time.LocalDate;
import java.time.format.DateTimeFormatter;
import java.util.ArrayList;
import java.util.List;

public class DateCaseTest extends UDF {

    public String evaluate(LocalDate startDate, Integer start, Integer end)  {
        if (startDate == null || start == null || end == null){
            return null;
        }
        DateTimeFormatter formatter = DateTimeFormatter.ofPattern("yyyy-MM-dd");
        LocalDate yesterday = LocalDate.now().minusDays(1);
        List<String> result = new ArrayList<>();
        for (int i = start; i <= end - 1; i++) {
            LocalDate oneDate = startDate.plusDays(i);
            if (oneDate.isAfter(yesterday)) break;
            String dateString = formatter.format(oneDate);
            result.add(dateString);
        }
        return String.join(",", result);
    }

}