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Writer/OutputStream to String?

Hi, I am now writing a servlet filter that should capture all response and modify them before reply to browser.

What I need to do is extract all data from the OutputStream/Writer and store them into String before String manipulation can happen. Then write the modified data to user.

Can anyone tell me how can I extract all data from OutputStream/Writer to String? or any easier way to perform this filtering? (I am actually trying to filter the output of Crystal Report JRC)

Thanks in advance.

bloodredsun

You need to do somehting similar to this http://www.onjava.com/pub/a/onjava/2003/11/19/filters.html and over-ride the response write() method.

bloodredsun

Technically that should be" override the write method of the ServletOutputStream used by the response".....

b612_forever

ASKER

I am actually want to remove certain string pattern from the response that is generated by Crystal Report, if I override the write() method, does that means I will process the data bte by byte?

bloodredsun

Convert the byte array to a String using the constructor

String byteString = new String(byte[] bytes) ;

do the replacement

byteString = byteString.replace("bert|ernie" , "") ;

and convert back

byte [] newBytes = byteString.getBytes() ;

and then write it out :-)

b612_forever

ASKER

thanks a lot bloodredsun, i am actually very new to servlet filter, can u show me the code sample on ur previous post?

thanks

bloodredsun

That is the code sample!?! What more do you need to know. Just override the ServletOutputStream in the way shown by the link in createing your own ResponseWrapper and do the conversion above.

b612_forever

ASKER

Thanks a lots. I am trying now...

instead of GZIPOutputStream, are me had to use some others output stream?

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bloodredsun

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b612_forever

ASKER

thanks a lot, bloodredsun. It had work.

and to moderator, I suggest to rename this question to something like "modify content with servlet filter" to ease others users.

thank you.