path: root/src/testcases/org/apache/poi/hssf/usermodel/TestHSSFDateUtil.java

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   this work for additional information regarding copyright ownership.
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package org.apache.poi.hssf.usermodel;

import java.util.Calendar;
import java.util.Date;
import java.util.GregorianCalendar;
import java.util.TimeZone;

import junit.framework.TestCase;

import org.apache.poi.hssf.HSSFTestDataSamples;
import org.apache.poi.hssf.model.Workbook;

/**
 * Class TestHSSFDateUtil
 *
 *
 * @author  Dan Sherman (dsherman at isisph.com)
 * @author  Hack Kampbjorn (hak at 2mba.dk)
 * @author  Pavel Krupets (pkrupets at palmtreebusiness dot com)
 * @author Alex Jacoby (ajacoby at gmail.com)
 * @version %I%, %G%
 */
public class TestHSSFDateUtil extends TestCase {

    public static final int CALENDAR_JANUARY = 0;
    public static final int CALENDAR_FEBRUARY = 1;
    public static final int CALENDAR_MARCH = 2;
    public static final int CALENDAR_APRIL = 3;
    public static final int CALENDAR_JULY = 6;
    public static final int CALENDAR_OCTOBER = 9;
    
    public TestHSSFDateUtil(String s)
    {
        super(s);
    }

    /**
     * Checks the date conversion functions in the HSSFDateUtil class.
     */

    public void testDateConversion()
            throws Exception
    {

        // Iteratating over the hours exposes any rounding issues.
        for (int hour = 0; hour < 23; hour++)
        {
            GregorianCalendar date      = new GregorianCalendar(2002, 0, 1,
                    hour, 1, 1);
            double            excelDate =
                    HSSFDateUtil.getExcelDate(date.getTime(), false);

            assertEquals("Checking hour = " + hour, date.getTime().getTime(),
                    HSSFDateUtil.getJavaDate(excelDate, false).getTime());
        }

        // check 1900 and 1904 date windowing conversions
        double excelDate = 36526.0;
        // with 1900 windowing, excelDate is Jan. 1, 2000
        // with 1904 windowing, excelDate is Jan. 2, 2004
        GregorianCalendar cal = new GregorianCalendar(2000,0,1); // Jan. 1, 2000
        Date dateIf1900 = cal.getTime();
        cal.add(GregorianCalendar.YEAR,4); // now Jan. 1, 2004
        cal.add(GregorianCalendar.DATE,1); // now Jan. 2, 2004
        Date dateIf1904 = cal.getTime();
        // 1900 windowing
        assertEquals("Checking 1900 Date Windowing",
                dateIf1900.getTime(),
                HSSFDateUtil.getJavaDate(excelDate,false).getTime());
        // 1904 windowing
        assertEquals("Checking 1904 Date Windowing",
                dateIf1904.getTime(),
                HSSFDateUtil.getJavaDate(excelDate,true).getTime());
    }

    /**
     * Checks the conversion of a java.util.date to Excel on a day when
     * Daylight Saving Time starts.
     */
    public void testExcelConversionOnDSTStart() {
        TimeZone cet = TimeZone.getTimeZone("Europe/Copenhagen");
        TimeZone.setDefault(cet);
        Calendar cal = new GregorianCalendar(2004, CALENDAR_MARCH, 28);
        for (int hour = 0; hour < 24; hour++) {

            // Skip 02:00 CET as that is the Daylight change time
            // and Java converts it automatically to 03:00 CEST
            if (hour == 2) {
                continue;
            }

            cal.set(Calendar.HOUR_OF_DAY, hour);
            Date javaDate = cal.getTime();
            double excelDate = HSSFDateUtil.getExcelDate(javaDate, false);
            double difference = excelDate - Math.floor(excelDate);
            int differenceInHours = (int) (difference * 24 * 60 + 0.5) / 60;
            assertEquals("Checking " + hour + " hour on Daylight Saving Time start date",
                    hour,
                    differenceInHours);
            assertEquals("Checking " + hour + " hour on Daylight Saving Time start date",
                    javaDate.getTime(),
                    HSSFDateUtil.getJavaDate(excelDate, false).getTime());
        }
    }

    /**
     * Checks the conversion of an Excel date to a java.util.date on a day when
     * Daylight Saving Time starts.
     */
    public void testJavaConversionOnDSTStart() {
        TimeZone cet = TimeZone.getTimeZone("Europe/Copenhagen");
        TimeZone.setDefault(cet);
        Calendar cal = new GregorianCalendar(2004, CALENDAR_MARCH, 28);
        double excelDate = HSSFDateUtil.getExcelDate(cal.getTime(), false);
        double oneHour = 1.0 / 24;
        double oneMinute = oneHour / 60;
        for (int hour = 0; hour < 24; hour++, excelDate += oneHour) {

            // Skip 02:00 CET as that is the Daylight change time
            // and Java converts it automatically to 03:00 CEST            
            if (hour == 2) {
                continue;
            }

            cal.set(Calendar.HOUR_OF_DAY, hour);
            Date javaDate = HSSFDateUtil.getJavaDate(excelDate, false);
            assertEquals("Checking " + hour + " hours on Daylight Saving Time start date",
                    excelDate,
                    HSSFDateUtil.getExcelDate(javaDate, false), oneMinute);
        }
    }

    /**
     * Checks the conversion of a java.util.Date to Excel on a day when
     * Daylight Saving Time ends.
     */
    public void testExcelConversionOnDSTEnd() {
        TimeZone cet = TimeZone.getTimeZone("Europe/Copenhagen");
        TimeZone.setDefault(cet);
        Calendar cal = new GregorianCalendar(2004, CALENDAR_OCTOBER, 31);
        for (int hour = 0; hour < 24; hour++) {
            cal.set(Calendar.HOUR_OF_DAY, hour);
            Date javaDate = cal.getTime();
            double excelDate = HSSFDateUtil.getExcelDate(javaDate, false);
            double difference = excelDate - Math.floor(excelDate);
            int differenceInHours = (int) (difference * 24 * 60 + 0.5) / 60;
            assertEquals("Checking " + hour + " hour on Daylight Saving Time end date",
                    hour,
                    differenceInHours);
            assertEquals("Checking " + hour + " hour on Daylight Saving Time start date",
                    javaDate.getTime(),
                    HSSFDateUtil.getJavaDate(excelDate, false).getTime());
        }
    }

    /**
     * Checks the conversion of an Excel date to java.util.Date on a day when
     * Daylight Saving Time ends.
     */
    public void testJavaConversionOnDSTEnd() {
        TimeZone cet = TimeZone.getTimeZone("Europe/Copenhagen");
        TimeZone.setDefault(cet);
        Calendar cal = new GregorianCalendar(2004, CALENDAR_OCTOBER, 31);
        double excelDate = HSSFDateUtil.getExcelDate(cal.getTime(), false);
        double oneHour = 1.0 / 24;
        double oneMinute = oneHour / 60;
        for (int hour = 0; hour < 24; hour++, excelDate += oneHour) {
            cal.set(Calendar.HOUR_OF_DAY, hour);
            Date javaDate = HSSFDateUtil.getJavaDate(excelDate, false);
            assertEquals("Checking " + hour + " hours on Daylight Saving Time start date",
                    excelDate,
                    HSSFDateUtil.getExcelDate(javaDate, false), oneMinute);
        }
    }
    
    /**
     * Tests that we deal with timezones properly
     */
    public void testCalendarConversion() {
        GregorianCalendar date = new GregorianCalendar(2002, 0, 1, 12, 1, 1);
        Date expected = date.getTime();
        double expectedExcel = HSSFDateUtil.getExcelDate(expected);

        // Iteratating over the hours exposes any rounding issues.
        for (int hour = -12; hour <= 12; hour++)
        {
            String id = "GMT" + (hour < 0 ? "" : "+") + hour + ":00";
            date.setTimeZone(TimeZone.getTimeZone(id));
            date.set(Calendar.HOUR_OF_DAY, 12);
            double excelDate = HSSFDateUtil.getExcelDate(date, false);
            Date javaDate = HSSFDateUtil.getJavaDate(excelDate);

            // Should match despite timezone
            assertEquals("Checking timezone " + id, expected.getTime(), javaDate.getTime());
        }
    }
    
    
    /**
     * Tests that we correctly detect date formats as such
     */
    public void testIdentifyDateFormats() {
        // First up, try with a few built in date formats
        short[] builtins = new short[] { 0x0e, 0x0f, 0x10, 0x16, 0x2d, 0x2e };
        for(int i=0; i<builtins.length; i++) {
            String formatStr = HSSFDataFormat.getBuiltinFormat(builtins[i]);
            assertTrue( HSSFDateUtil.isInternalDateFormat(builtins[i]) );
            assertTrue( HSSFDateUtil.isADateFormat(builtins[i],formatStr) );
        }
        
        // Now try a few built-in non date formats
        builtins = new short[] { 0x01, 0x02, 0x17, 0x1f, 0x30 };
        for(int i=0; i<builtins.length; i++) {
            String formatStr = HSSFDataFormat.getBuiltinFormat(builtins[i]);
            assertFalse( HSSFDateUtil.isInternalDateFormat(builtins[i]) );
            assertFalse( HSSFDateUtil.isADateFormat(builtins[i],formatStr) );
        }
        
        // Now for some non-internal ones
        // These come after the real ones
        int numBuiltins = HSSFDataFormat.getNumberOfBuiltinBuiltinFormats();
        assertTrue(numBuiltins < 60);
        short formatId = 60;
        assertFalse( HSSFDateUtil.isInternalDateFormat(formatId) );
        
        // Valid ones first
        String[] formats = new String[] {
                "yyyy-mm-dd", "yyyy/mm/dd", "yy/mm/dd", "yy/mmm/dd",
                "dd/mm/yy", "dd/mm/yyyy", "dd/mmm/yy",
                "dd-mm-yy", "dd-mm-yyyy",
                "DD-MM-YY", "DD-mm-YYYY",
                "dd\\-mm\\-yy", // Sometimes escaped
                
                // These crazy ones are valid
                "yyyy-mm-dd;@", "yyyy/mm/dd;@",
                "dd-mm-yy;@", "dd-mm-yyyy;@",
                // These even crazier ones are also valid
                // (who knows what they mean though...)
                "[$-F800]dddd\\,\\ mmm\\ dd\\,\\ yyyy",
                "[$-F900]ddd/mm/yyy",
        };
        for(int i=0; i<formats.length; i++) {
            assertTrue( HSSFDateUtil.isADateFormat(formatId, formats[i]) );
        }
        
        // Then time based ones too
        formats = new String[] {
                "yyyy-mm-dd hh:mm:ss", "yyyy/mm/dd HH:MM:SS", 
                "mm/dd HH:MM", "yy/mmm/dd SS",
        };
        for(int i=0; i<formats.length; i++) {
            assertTrue( HSSFDateUtil.isADateFormat(formatId, formats[i]) );
        }
        
        // Then invalid ones
        formats = new String[] {
                "yyyy*mm*dd", 
                "0.0", "0.000",
                "0%", "0.0%",
                "", null
        };
        for(int i=0; i<formats.length; i++) {
            assertFalse( HSSFDateUtil.isADateFormat(formatId, formats[i]) );
        }
        
        // And these are ones we probably shouldn't allow,
        //  but would need a better regexp
        formats = new String[] {
                "yyyy:mm:dd", 
        };
        for(int i=0; i<formats.length; i++) {
        //    assertFalse( HSSFDateUtil.isADateFormat(formatId, formats[i]) );
        }
    }

    /**
     * Test that against a real, test file, we still do everything
     *  correctly
     */
    public void testOnARealFile() throws Exception {

        HSSFWorkbook workbook = HSSFTestDataSamples.openSampleWorkbook("DateFormats.xls");
        HSSFSheet sheet       = workbook.getSheetAt(0);
        Workbook wb           = workbook.getWorkbook();
        
        HSSFRow  row;
        HSSFCell cell;
        HSSFCellStyle style;
        
        double aug_10_2007 = 39304.0;
        
        // Should have dates in 2nd column
        // All of them are the 10th of August
        // 2 US dates, 3 UK dates
        row  = sheet.getRow(0);
        cell = row.getCell((short)1);
        style = cell.getCellStyle();
        assertEquals(aug_10_2007, cell.getNumericCellValue(), 0.0001);
        assertEquals("d-mmm-yy", style.getDataFormatString(wb));
        assertTrue(HSSFDateUtil.isInternalDateFormat(style.getDataFormat()));
        assertTrue(HSSFDateUtil.isADateFormat(style.getDataFormat(), style.getDataFormatString(wb)));
        assertTrue(HSSFDateUtil.isCellDateFormatted(cell));
        
        row  = sheet.getRow(1);
        cell = row.getCell((short)1);
        style = cell.getCellStyle();
        assertEquals(aug_10_2007, cell.getNumericCellValue(), 0.0001);
        assertFalse(HSSFDateUtil.isInternalDateFormat(cell.getCellStyle().getDataFormat()));
        assertTrue(HSSFDateUtil.isADateFormat(style.getDataFormat(), style.getDataFormatString(wb)));
        assertTrue(HSSFDateUtil.isCellDateFormatted(cell));
        
        row  = sheet.getRow(2);
        cell = row.getCell((short)1);
        style = cell.getCellStyle();
        assertEquals(aug_10_2007, cell.getNumericCellValue(), 0.0001);
        assertTrue(HSSFDateUtil.isInternalDateFormat(cell.getCellStyle().getDataFormat()));
        assertTrue(HSSFDateUtil.isADateFormat(style.getDataFormat(), style.getDataFormatString(wb)));
        assertTrue(HSSFDateUtil.isCellDateFormatted(cell));
        
        row  = sheet.getRow(3);
        cell = row.getCell((short)1);
        style = cell.getCellStyle();
        assertEquals(aug_10_2007, cell.getNumericCellValue(), 0.0001);
        assertFalse(HSSFDateUtil.isInternalDateFormat(cell.getCellStyle().getDataFormat()));
        assertTrue(HSSFDateUtil.isADateFormat(style.getDataFormat(), style.getDataFormatString(wb)));
        assertTrue(HSSFDateUtil.isCellDateFormatted(cell));
        
        row  = sheet.getRow(4);
        cell = row.getCell((short)1);
        style = cell.getCellStyle();
        assertEquals(aug_10_2007, cell.getNumericCellValue(), 0.0001);
        assertFalse(HSSFDateUtil.isInternalDateFormat(cell.getCellStyle().getDataFormat()));
        assertTrue(HSSFDateUtil.isADateFormat(style.getDataFormat(), style.getDataFormatString(wb)));
        assertTrue(HSSFDateUtil.isCellDateFormatted(cell));
    }
    
    public void testDateBug_2Excel() {
        assertEquals(59.0, HSSFDateUtil.getExcelDate(createDate(1900, CALENDAR_FEBRUARY, 28), false), 0.00001);
        assertEquals(61.0, HSSFDateUtil.getExcelDate(createDate(1900, CALENDAR_MARCH, 1), false), 0.00001);

        assertEquals(37315.00, HSSFDateUtil.getExcelDate(createDate(2002, CALENDAR_FEBRUARY, 28), false), 0.00001);
        assertEquals(37316.00, HSSFDateUtil.getExcelDate(createDate(2002, CALENDAR_MARCH, 1), false), 0.00001);
        assertEquals(37257.00, HSSFDateUtil.getExcelDate(createDate(2002, CALENDAR_JANUARY, 1), false), 0.00001);
        assertEquals(38074.00, HSSFDateUtil.getExcelDate(createDate(2004, CALENDAR_MARCH, 28), false), 0.00001);
    }
    
    public void testDateBug_2Java() {
        assertEquals(createDate(1900, CALENDAR_FEBRUARY, 28), HSSFDateUtil.getJavaDate(59.0, false));
        assertEquals(createDate(1900, CALENDAR_MARCH, 1), HSSFDateUtil.getJavaDate(61.0, false));
        
        assertEquals(createDate(2002, CALENDAR_FEBRUARY, 28), HSSFDateUtil.getJavaDate(37315.00, false));
        assertEquals(createDate(2002, CALENDAR_MARCH, 1), HSSFDateUtil.getJavaDate(37316.00, false));
        assertEquals(createDate(2002, CALENDAR_JANUARY, 1), HSSFDateUtil.getJavaDate(37257.00, false));
        assertEquals(createDate(2004, CALENDAR_MARCH, 28), HSSFDateUtil.getJavaDate(38074.00, false));
    }
    
    public void testDate1904() {
        assertEquals(createDate(1904, CALENDAR_JANUARY, 2), HSSFDateUtil.getJavaDate(1.0, true));
        assertEquals(createDate(1904, CALENDAR_JANUARY, 1), HSSFDateUtil.getJavaDate(0.0, true));
        assertEquals(0.0, HSSFDateUtil.getExcelDate(createDate(1904, CALENDAR_JANUARY, 1), true), 0.00001);
        assertEquals(1.0, HSSFDateUtil.getExcelDate(createDate(1904, CALENDAR_JANUARY, 2), true), 0.00001);
        
        assertEquals(createDate(1998, CALENDAR_JULY, 5), HSSFDateUtil.getJavaDate(35981, false));
        assertEquals(createDate(1998, CALENDAR_JULY, 5), HSSFDateUtil.getJavaDate(34519, true));
        
        assertEquals(35981.0, HSSFDateUtil.getExcelDate(createDate(1998, CALENDAR_JULY, 5), false), 0.00001);
        assertEquals(34519.0, HSSFDateUtil.getExcelDate(createDate(1998, CALENDAR_JULY, 5), true), 0.00001);
    }
    
    private Date createDate(int year, int month, int day) {
        Calendar c = new GregorianCalendar();
        c.set(year, month, day, 0, 0, 0);
        c.set(Calendar.MILLISECOND, 0);
        return c.getTime();
    }
    
    /**
     * Check if HSSFDateUtil.getAbsoluteDay works as advertised.
     */
    public void testAbsoluteDay() {
        // 1 Jan 1900 is 1 day after 31 Dec 1899
        GregorianCalendar calendar = new GregorianCalendar(1900, 0, 1);
        assertEquals("Checking absolute day (1 Jan 1900)", 1, HSSFDateUtil.absoluteDay(calendar, false));
        // 1 Jan 1901 is 366 days after 31 Dec 1899
        calendar = new GregorianCalendar(1901, 0, 1);
        assertEquals("Checking absolute day (1 Jan 1901)", 366, HSSFDateUtil.absoluteDay(calendar, false));
    }
    
    public static void main(String [] args) {
        System.out
                .println("Testing org.apache.poi.hssf.usermodel.TestHSSFDateUtil");
        junit.textui.TestRunner.run(TestHSSFDateUtil.class);
    }
}