File Bytes to String

Question

I'm trying to decode a file, when i use this codepublic void returnFile(String filename) throws FileNotFoundException, IOException {
//       A FileInputStream is for bytes
       FileInputStream fis = null;
       try {
            fis = new FileInputStream(filename);
            byte[] buf = new byte[4 * 1024];  // 4K buffer
            int bytesRead;
            while ((bytesRead = fis.read(buf)) != -1) {
                 out.write(buf, 0, bytesRead);
       finally {
            if (fis != null) fis.close();
  }with the result beeing printed directly,
but in an other case i don't have access to the out variable, so i want to return a string from a function, so i have thispublic static String returnFile2(String filename)
     throws FileNotFoundException, IOException {
//          A FileInputStream is for bytes
          FileInputStream fis = null;
          StringBuffer buffer = new StringBuffer();
          try {
               fis = new FileInputStream("C:/eclipse/workspace/rbtTranform/WebContent/images/15x15/V.gif");
               byte[] buf = new byte[4 * 1024];  // 4K buffer
               int bytesRead;
               while ((bytesRead = fis.read(buf)) != -1) {
                    buffer.append(new String(buf).trim());
          finally {
               if (fis != null) fis.close();
          return buffer.toString();
     }The problem is that in this second funcion, i return the file contents as a String, they are not like in the first function, and i can't "re-encode" the data back to original file (as i can with the first function)
Can anyone help me?

Answer 1

I want to make a MultiPart Response, i am using this in a XSLT file that call a function that is supposed to take a file and return its contents as a String (the second method i posted)
I can't use the first one, because from the XSLT i can't send the out parameter, so that i could write on it
That's also why i can't handle and image as an image
It's a bit confusing i know
But if you could gimme a hint...