Solved

How to encode a binary and text file into a string

Posted on 2004-08-16
7
221 Views
Last Modified: 2010-03-31
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.
0
Comment
Question by:borg48
[X]
Welcome to Experts Exchange

Add your voice to the tech community where 5M+ people just like you are talking about what matters.

  • Help others & share knowledge
  • Earn cash & points
  • Learn & ask questions
  • 3
7 Comments
 
LVL 35

Expert Comment

by:girionis
ID: 11817953
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);
0
 
LVL 35

Expert Comment

by:girionis
ID: 11818079
You might also want to take a look here: http://javaalmanac.com/egs/java.net/Base64.html
0
 
LVL 9

Expert Comment

by:Venci75
ID: 11818082
If the only reason for encoding a binary file is that you have to store it into a database, you can use BLOB field
0
 

Author Comment

by:borg48
ID: 11821682
How would i then take the byte:
bytes [] decodedPDF = BASE64Decoder().decodeBuffer(endodedString);

and output it back to a file?
0
 
LVL 35

Accepted Solution

by:
girionis earned 125 total points
ID: 11827855
You can use a FileOutputStream and use one of its write methods that take a byte array as a parameter.
0

Featured Post

Free Tool: ZipGrep

ZipGrep is a utility that can list and search zip (.war, .ear, .jar, etc) archives for text patterns, without the need to extract the archive's contents.

One of a set of tools we're offering as a way to say thank you for being a part of the community.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

Suggested Solutions

Title # Comments Views Activity
xampp tool 12 60
how to install java on RHEL image on EC2 4 58
Running JavaFX on the Raspberry Pi 27 151
Java array sort 10 35
After being asked a question last year, I went into one of my moods where I did some research and code just for the fun and learning of it all.  Subsequently, from this journey, I put together this article on "Range Searching Using Visual Basic.NET …
Java Flight Recorder and Java Mission Control together create a complete tool chain to continuously collect low level and detailed runtime information enabling after-the-fact incident analysis. Java Flight Recorder is a profiling and event collectio…
Viewers will learn about if statements in Java and their use The if statement: The condition required to create an if statement: Variations of if statements: An example using if statements:
This tutorial explains how to use the VisualVM tool for the Java platform application. This video goes into detail on the Threads, Sampler, and Profiler tabs.

730 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question