From ffe4a6d83e3323b370fa4352faa16419af80f1c9 Mon Sep 17 00:00:00 2001 From: Avik Sengupta Date: Thu, 13 Jun 2002 17:17:24 +0000 Subject: [PATCH] Add util method to check date formatting in Excel, submitted by Jason Hoffman git-svn-id: https://svn.apache.org/repos/asf/jakarta/poi/trunk@352695 13f79535-47bb-0310-9956-ffa450edef68 --- src/documentation/xdocs/faq.xml | 62 ++++--------------- .../poi/hssf/usermodel/HSSFDateUtil.java | 40 ++++++++++++ 2 files changed, 53 insertions(+), 49 deletions(-) diff --git a/src/documentation/xdocs/faq.xml b/src/documentation/xdocs/faq.xml index 71957db75..05a172291 100644 --- a/src/documentation/xdocs/faq.xml +++ b/src/documentation/xdocs/faq.xml @@ -37,7 +37,7 @@ Does HSSF support protected spreadsheets? - Protecting a spreadsheet encripts it. We wont touch encription because we're not legally educated + Protecting a spreadsheet encrypts it. We wont touch encryption because we're not legally educated and don't understand the full implications of trying to implement this. If you wish to have a go at this feel free to add it as a plugin module. We wont be hosting it here however. @@ -48,20 +48,15 @@ Excel stores dates as numbers therefore the only way to determine if a cell is - actually stored as a date is to look at the formatting. This solution from - Jason Hoffman: -

- Okay, here is a little code I used to determine if the cell was a number or - date, and then format appropriately. I hope it helps. I keep meaning to - submit a patch with the helper method below.... but just haven't had a - chance. -

+ actually stored as a date is to look at the formatting. There is a helper method + in HSSFDateUtil (since after 1.6.0-dev) that checks for this. + Thanks to Jason Hoffman for providing the solution. -/////// code snippet //////////// -case HSSFCell.CELL_TYPE_NUMERIC: + + case HSSFCell.CELL_TYPE_NUMERIC: double d = cell.getNumericCellValue(); // test if a date! - if (isCellDateFormatted(cell)) { + if (HSSFDateUtil.isCellDateFormatted(cell)) { // format in form of M/D/YY cal.setTime(HSSFDateUtil.getJavaDate(d)); cellText = @@ -70,45 +65,13 @@ case HSSFCell.CELL_TYPE_NUMERIC: cal.get(Calendar.DAY_OF_MONTH) + "/" + cellText; } -/////// end code snippet //////////// -// HELPER METHOD BELOW TO DETERMINE IF DATE -// method to determine if the cell is a date, versus a number... -public static boolean isCellDateFormatted(HSSFCell cell) { - boolean bDate = false; - double d = cell.getNumericCellValue(); - if ( HSSFDateUtil.isValidExcelDate(d) ) { - HSSFCellStyle style = cell.getCellStyle(); - int i = style.getDataFormat(); - switch(i) { - // Internal Date Formats as described on page 427 in - // Microsoft Excel Dev's Kit... - case 0x0e: - case 0x0f: - case 0x10: - case 0x11: - case 0x12: - case 0x13: - case 0x14: - case 0x15: - case 0x16: - case 0x2d: - case 0x2e: - case 0x2f: - bDate = true; - break; - - default: - bDate = false; - break; - } - } - return bDate; - } + + I'm trying to stream an XLS file from a servlet and I'm having some trouble. What's the problem? @@ -125,8 +88,9 @@ public static boolean isCellDateFormatted(HSSFCell cell) { The problem in most versions of IE is that it does not use the mime type on the HTTP response to determine the file type; rather it uses the file extension on the request. Thus you might want to add a .xls to your request - string. For example http://yourserver.com/myServelet.xls?param1=xx. Sometimes - a request like http://yourserver.com/myServelet?param1=xx&dummy=file.xls is also + string. For example http://yourserver.com/myServelet.xls?param1=xx. This is + easily accomplished through URL mapping in any servlet container. Sometimes + a request like http://yourserver.com/myServelet?param1=xx&dummy=file.xls is also known to work.

@@ -137,7 +101,7 @@ public static boolean isCellDateFormatted(HSSFCell cell) { request as mentioned above.)

- Note also that sometimes when you request a document that is opened with an + Note also that when you request a document that is opened with an external handler, IE sometimes makes two requests to the webserver. So if your generating process is heavy, it makes sense to write out to a temporary file, so that multiple requests happen for a static file. diff --git a/src/java/org/apache/poi/hssf/usermodel/HSSFDateUtil.java b/src/java/org/apache/poi/hssf/usermodel/HSSFDateUtil.java index 4a6caf10a..9ab294f3f 100644 --- a/src/java/org/apache/poi/hssf/usermodel/HSSFDateUtil.java +++ b/src/java/org/apache/poi/hssf/usermodel/HSSFDateUtil.java @@ -141,6 +141,46 @@ public class HSSFDateUtil return null; } } + + /** + * Check if a cell contains a date + * Since dates are stored internally in Excel as double values + * we infer it is a date if it is formatted as such. + */ + public static boolean isCellDateFormatted(HSSFCell cell) { + if (cell == null) return false; + boolean bDate = false; + + double d = cell.getNumericCellValue(); + if ( HSSFDateUtil.isValidExcelDate(d) ) { + HSSFCellStyle style = cell.getCellStyle(); + int i = style.getDataFormat(); + switch(i) { + // Internal Date Formats as described on page 427 in + // Microsoft Excel Dev's Kit... + case 0x0e: + case 0x0f: + case 0x10: + case 0x11: + case 0x12: + case 0x13: + case 0x14: + case 0x15: + case 0x16: + case 0x2d: + case 0x2e: + case 0x2f: + bDate = true; + break; + + default: + bDate = false; + break; + } + } + return bDate; + } + /** * Given a double, checks if it is a valid Excel date.