Read bytecode of a PDF file

Question

Hello
I must read Bytecode of a .PDF file but the method I use is too slow.
Is there anybody can suggest me a faster or better method, please?
This is my code
public String scriviBC (String strPercorso, String strFile) {
binario = "";
try {
File file = new File (strPercorso + strFile);
int i;
InputStream input = new FileInputStream(file);
BufferedInputStream in = new BufferedInputStream(input);
BufferedReader reader = new BufferedReader(new InputStreamReader(in));
while ((i = reader.read()) != -1) {
binario += i;
risultato = binario;
System.out.println(binario);
} // END try
catch(Exception e) {
System.out.println("error"); e.printStackTrace();
risultato = e.toString();
} finally {
return risultato;
Ps I've already tried without buffering but it's the same.
Excuse me for my bad english and thank you!

Answer 1

Use Code Tags
The reasons this is slow is:
1) reading a single byte at a time (reader.read())
2) creating a new string each loop (for each char).
To speed it up, you want to use the read method that takes an array, and read multiply letters at a time, and use a StringBuffer.
Also are you doing what you want to do?
For a start you say "Bytecode of a .PDF", but then you are reading using a "BufferedReader" which is for textual data, when a PDF is bytes (and so you should be using a Stream, not a Reader).
Then you creating a long string of this (as understand the code, as a string of numbers like "1231878394794237", which would be not be useable), for bytes, would'nt a byte array or alike be a better option?