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how to read a file data into byte array

 
Greenhorn
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Hi,

I want to read a file content into byte array from server and I don't know how big the file is. Can any one help how do I read a file content into a byte array? (the file may 1MB or 10k size).
Any help please..

Thanks.
 
Bartender
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Use a ByteArrayOutputStream:


This class implements an output stream in which the data is written into a byte array. The buffer automatically grows as data is written to it. The data can be retrieved using toByteArray()

 
taylor mark
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Hi Right now I am using the following code to read the data from file into a StringBuffer. This is working fine but the problems is with new line character.
protected String read(String fileName) {
StringBuffer buffer = new StringBuffer();
String newline = System.getProperty("line.separator");
if(fileName == null) return null;
File file = new File(fileName);
try{
BufferedReader reader = new BufferedReader(new FileReader(fileName));
String line = "";
while ( (line = reader.readLine()) != null) {
buffer.append(line);
buffer.append(newline);
}
}catch(Exception e) { throw new RuntimeException (e); }
return buffer.toString().trim();
}

The new line character is diff on windows and unix. FileReader removes the line character. That's why I am addding that new line character again.
The file contains new line. I want to read that new line also.
How do I get new line also in the buffer instead of appending after reading each line. I don't want append new line after reading each line. I want to read new line also.
Any otherway or sample code please...

Thanks,
 
taylor mark
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Hi Joe,

Can you provide sample code that reads a file using ByteArrayOutputStream()?

Thanks,
 
taylor mark
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Hi,

Can any one provide some sample code that reads new line character also?
I don't want to append newline after reading each line.

Thanks.
 
taylor mark
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Hi I got solution for the problem. I am reading the file using the following code.
import java.io.*;

class Ran {
public static void main(String ars[]) throws Exception{
FileInputStream fis = new FileInputStream("SSO.txt");
int x= fis.available();
byte b[]= new byte[x];
fis.read(b);
String content = new String(b);
System.out.println(content);
}
}

I want to read the hole file as it is. The above code does that.

Thanks.
 
Joe Ess
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A trap many people fall into: InputStream.available() does not return the size of the file:

Returns the number of bytes that can be read (or skipped over) from this input stream without blocking by the next caller of a method for this input stream


Javadoc for InputStream

Also, FileReader does not consume line separators, BufferedReader does:


public String readLine() throws IOException

Read a line of text. A line is considered to be terminated by any one of a line feed ('\n'), a carriage return ('\r'), or a carriage return followed immediately by a linefeed.

Returns:
A String containing the contents of the line, not including any line-termination characters, or null if the end of the stream has been reached


Javadoc for BufferedReader

Take a look at this example from the The Java Developers Almanac
 
Greenhorn
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My appologize, for not being more clear.
Questions:
1.Where am I suppose to place the file? As far as the path and location is concerened?
2. Once it it is working, how do I actually read out the records to the screen/console or a new file.

I am thinking that I should use :
while next().....//as long as there are reords in the file.

Can anyone give some directions?
Thanks again
 
Jill Nilsson
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Please disregard the previous comment, I posted on the wrong thread.
 
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