Android: How to write to a certain line, Java -

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hello guys , thanks,

i wondering how write line in java android. here write method:

    public void savelesson(int lessons2, int problem2, int mlessons2, int mproblem2, string checkaccuracy) {      string newline = system.getproperty("line.separator");     final string saved = new string(lessons2 + newline + problem2 + newline + mlessons2 + newline + mproblem2 + newline + checkaccuracy);          fileoutputstream fout = null;         try { // catches ioexception below                 fout = openfileoutput("lessonstore.properties",                 context.mode_private);     } catch (filenotfoundexception e) {         // todo auto-generated catch block         e.printstacktrace();     }         outputstreamwriter osw = new outputstreamwriter(fout);           // write string file         try {             osw.write(saved);         /* ensure          * written out , close */         osw.flush();         osw.close();         } catch (ioexception e) {              toast andeggs = toast.maketext(lessons.this, "error while writing...", toast.length_short);             andeggs.show();             // todo auto-generated catch block             e.printstacktrace();         }  }

how make overwrite line 3, instead of whole thing because save variables , nice have save 1 instead of them all.

how make overwrite line 3

you don't!

never modify file in line; if line shorter original? if it's longer? os won't automagically expand/shrink file you!

write contents another file, replace original.


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