java - How to correctly write CRLF for maximum portability? -

i have software creates file send bank software reads file. software rejecting file because says file not have crlf line separator. until now, file created on windows machines, , line separator use "\r\n". searched , found out if on windows, generates in different way generating on linux or mac. how can generate crlf independent of platform?

update 1

this method use create file, replace \r\n \n , \n \r\n, ensure when whoever calls method passing \n line separator, file generated correctly \r\n:

public static void createfile(string filepath,string content){     try{         file parentfile=new file(filepath).getparentfile();         if(parentfile!=null && !parentfile.exists()){             parentfile.mkdirs();         }         bufferedwriter bw=new bufferedwriter(new filewriter(filepath));         bw.write(content.replaceall("\r\n","\n").replaceall("\n","\r\n"));         bw.flush();         bw.close();     }catch(exception e){         throw new runtimeexception("error creating file", e);     } } 

the \r\n prints 2 characters cr , lf on platforms. http://docs.oracle.com/javase/tutorial/java/data/characters.html

\n insert newline in text @ point.
\r insert carriage return in text @ point.

you can test with

   filewriter fw = new filewriter("test");    fw.write("\r\n");    fw.close();    fileinputstream fis = new fileinputstream("test");    for(int ch; (ch = fis.read())!=-1;) {        system.out.printf("0x%02x%n", ch);    }    fis.close(); 

run on ubuntu machine prints

0x0d 0x0a