ch.ethz.system.mt.tpch.GenerateUtils.java Source code

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Here is the source code for ch.ethz.system.mt.tpch.GenerateUtils.java

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/*
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package ch.ethz.system.mt.tpch;

import com.google.common.collect.ImmutableList;

import java.math.BigDecimal;
import java.util.List;

import static java.util.Locale.ENGLISH;

public final class GenerateUtils {
    //
    // Partitioning Utils
    //

    public static long calculateRowCount(int scaleBase, double scaleFactor, int part, int partCount) {
        long totalRowCount = (long) (scaleBase * scaleFactor);
        long rowCount = totalRowCount / partCount;
        if (part == partCount) {
            // for the last part, add the remainder rows
            rowCount = rowCount + (totalRowCount % partCount);
        }
        return rowCount;
    }

    public static long calculateStartIndex(int scaleBase, double scaleFactor, int part, int partCount) {
        long totalRowCount = (long) (scaleBase * scaleFactor);

        long rowsPerPart = totalRowCount / partCount;
        return rowsPerPart * (part - 1);
    }

    //
    // Date Utils
    //

    /**
     * The value of 1970-01-01 in the date generator system
     */
    public static final int GENERATED_DATE_EPOCH_OFFSET = 83966;

    public static final int MIN_GENERATE_DATE = 92001;
    private static final int CURRENT_DATE = 95168;
    public static final int TOTAL_DATE_RANGE = 2557;

    private static final int[] MONTH_YEAR_DAY_START = new int[] { 0, 31, 59, 90, 120, 151, 181, 212, 243, 273, 304,
            334, 365, };

    private static final List<String> DATE_STRING_INDEX = makeDateStringIndex();

    public static int toEpochDate(int generatedDate) {
        return generatedDate - GENERATED_DATE_EPOCH_OFFSET;
    }

    public static String formatDate(int epochDate) {
        return DATE_STRING_INDEX.get(epochDate - (MIN_GENERATE_DATE - GENERATED_DATE_EPOCH_OFFSET));
    }

    private static List<String> makeDateStringIndex() {
        ImmutableList.Builder<String> dates = ImmutableList.builder();
        for (int i = 0; i < TOTAL_DATE_RANGE; i++) {
            dates.add(makeDate(i + 1));
        }

        return dates.build();
    }

    private static String makeDate(int index) {
        int y = julian(index + MIN_GENERATE_DATE - 1) / 1000;
        int d = julian(index + MIN_GENERATE_DATE - 1) % 1000;

        int m = 0;
        while (d > MONTH_YEAR_DAY_START[m] + leapYearAdjustment(y, m)) {
            m++;
        }
        int dy = d - MONTH_YEAR_DAY_START[m - 1] - ((isLeapYear(y) && m > 2) ? 1 : 0);

        return String.format(ENGLISH, "19%02d-%02d-%02d", y, m, dy);
    }

    private static int leapYearAdjustment(int year, int month) {
        return ((isLeapYear(year) && (month) >= 2) ? 1 : 0);
    }

    public static boolean isInPast(int date) {
        return julian(date) <= CURRENT_DATE;
    }

    private static int julian(int date) {
        int offset = date - MIN_GENERATE_DATE;
        int result = MIN_GENERATE_DATE;

        while (true) {
            int year = result / 1000;
            int yearEnd = year * 1000 + 365 + (isLeapYear(year) ? 1 : 0);
            if (result + offset <= yearEnd) {
                break;
            }

            offset -= yearEnd - result + 1;
            result += 1000;
        }
        return (result + offset);
    }

    private static boolean isLeapYear(int year) {
        return year % 4 == 0 && year % 100 != 0;
    }

    //
    // Format utils
    //

    public static String formatMoney(long value) {
        // todo there must be a better way to do this
        return new BigDecimal(value).divide(new BigDecimal(100)).setScale(2).toString();
    }
}