Link to home
Start Free TrialLog in
Avatar of borg48
borg48

asked on

How to encode a binary and text file into a string

I'm using the java commons base64 api.  Here is what i need to do.  My program creates a pdf and html file.  I need to base64 encode each file into a string and then store it into a text field in a database.  and at a later date retrieve it and decode it and store it back into the file type it should be.   But i'm not quite to sure.  Here is what i have so far:

                   File file = new File( "D:/projects/base64code/test.pdf" );
                   File fileOut = new File( "D:/projects/base64code/test_out.pdf" );

                   byte[] scratch = new byte[8*1024];

                   FileInputStream in = new FileInputStream(file);
                   FileOutputStream out = new FileOutputStream(fileOut);

//                    These next two give you super turbo performance speed
                   BufferedInputStream bin = new BufferedInputStream(in);
                   BufferedOutputStream bout = new BufferedOutputStream(out);

//                    If you don't loop, then you're probably losing data
                   int consumed = 0;
                   do {
                        consumed = bin.read( scratch );
                        if ( consumed > 0 )
                        {
                            bout.write( scratch, 0, consumed );
                        }
                   } while ( consumed >= 0 );
                  
                   byte[] encodedArray = Base64.encodeBase64( scratch );
                  
                  
                   byte[] decodeArray = new byte[8*1024];
                   decodeArray = Base64.decodeBase64(encodedArray);


So what i'm trying to do in this example is:
1.  Encode the pdf file.
2.  Retrieve the string value so i can store it into a column in a database table ( I'm not sure how to do that here)
3.  Take the string value (just to test that i can convert back to a byte and decode) and convert into a byte then save to the appropriate file name.

Thanks in advance.
Avatar of girionis
girionis
Flag of Greece image

You need to encode your byte array. Lets say that your byte array that holds the pdf is called "pdfInBytes" you can do:

String encodedString = BASE64Encoder().encode(pdfInBytes);

To decode it back to a bytes array you use:

bytes [] decodedPDF = BASE64Decoder().decodeBuffer(endodedString);
You might also want to take a look here: http://javaalmanac.com/egs/java.net/Base64.html
Avatar of Venci75
Venci75

If the only reason for encoding a binary file is that you have to store it into a database, you can use BLOB field
Avatar of borg48

ASKER

How would i then take the byte:
bytes [] decodedPDF = BASE64Decoder().decodeBuffer(endodedString);

and output it back to a file?
ASKER CERTIFIED SOLUTION
Avatar of girionis
girionis
Flag of Greece image

Link to home
membership
This solution is only available to members.
To access this solution, you must be a member of Experts Exchange.
Start Free Trial