Hello Mark,
I appreciate you help.
Regards,
JG
MSB wrote:
>
> You're welcome James. All the best with your project and, if you need any
> further help, just drop an message onto the list.
>
> Yours
>
> Mark B
>
>
> James Geroge wrote:
>>
>> Hello Mark,
>> Thanks for your suggestions.
>> I tried to raise a null pointer exception with WorkbookFactory Class, but
>> did not work so done a try catch and able to get a handler to the
>> requirement i had.
>>
>> and Thanks for the other suggestions too.
>>
>> The code below...
>> try
>> {
>> if (WorkbookFactory.create(input)!=null)
>> {
>> log("GOOD FILE");
>> }
>> else
>> {
>> log("Invalid input file Or Not a valid Excel file");
>> }
>> }
>> catch (Exception e1) {
>> //e1.printStackTrace();
>> log("Invalid input file Or Not a valid Excel file");
>> return; // no need to process if it is not an excel
>> }
>>
>> Thanks,
>> James George
>>
>>
>> MSB wrote:
>>>
>>> Hello James,
>>>
>>> The most obvious answer is the WorkbookFactory class -
>>> http://poi.apache.org/apidocs/org/apache/poi/ss/usermodel/WorkbookFactory.html
>>> - if you have a valid Excel workbook then it will return an instance of
>>> either the XSSF or HSSFWorkbook class. That does impose some overhead of
>>> course as the Excel file will effectively be opened which could take a
>>> few moments and tie up some memory.
>>>
>>> The other option would be to look at the file header, the first few
>>> bytes of the file. There is a website - filext.com - that includes
>>> provides this sort of information. For example, here is the information
>>> for the .xls file format http://filext.com/file-extension/XLS and this
>>> for the .xlsx http://filext.com/file-extension/xlsx. In essence, you
>>> would open a stream onto the file, recover the first few bytes and see
>>> if they match either pattern; but I do not know whether this is an
>>> entirely fail safe option.
>>>
>>> Yours
>>>
>>> Mark B
>>>
>>> PS. You have posted this onto the the dev list when if really ought to
>>> be posted onto the user list. The dev list is where you would post if
>>> you were experiencing problems with the API - for example a particular
>>> file provoking exceptions - or if you wanted to ask for an enhancement.
>>> Furthermore, fewer people view the dev list and you are reducing your
>>> chances of receiving a response to your question.
>>>
>>>
>>>
>>> James Geroge wrote:
>>>>
>>>> Hi Friends,
>>>> Is there a way to know the file is an excel file without manipulating
>>>> the file extension, as the users can send the excel files in format
>>>> like below.
>>>> Test
>>>> Test.xls
>>>> Test.xlsx
>>>> Test.xlsxxlsx(by renaming the file using windows explorer)
>>>> Test.xlsabcd (by renaming
>>>>
>>>> Thanks,
>>>> James George.
>>>>
>>>
>>>
>>
>>
>
>
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