Re: Why is Java so slow????

From:

ram@zedat.fu-berlin.de (Stefan Ram)

Newsgroups:

comp.lang.java.programmer

Date:

19 Nov 2007 23:45:22 GMT

Message-ID:

<autoflush-20071120004331@ram.dialup.fu-berlin.de>

Mark Space <markspace@sbc.global.net> writes:

This *still* causes the output to be flushed. Remove the \n and I get a
50% speed increase (halves runtime). Is there no way to set the
autoflush for System.out to false?

  I have written the following attempt.
  But I have not tested whether it works.
  (The exception handling still can be simplified.)

/* NB: The "false" below is intended to turn autoflush off. */
public class Main
{
  public static java.io.PrintStream newOutPrintWithAutoflushTurnedOff()
  { java.io.PrintStream outPrint = null;
    java.lang.Exception ex = null;
    final java.io.FileDescriptor outDescriptor =
    java.io.FileDescriptor.out;
    try{ java.io.FileOutputStream outStream =
      new java.io.FileOutputStream( outDescriptor );
      outPrint = new java.io.PrintStream( outStream, false ); }
    catch( final java.lang.SecurityException e ){ ex = e; }
    if( ex != null )throw new java.lang.RuntimeException( ex );
    return outPrint; }

  public static void setOutWithAutoflushTurnedOff()
  { java.io.PrintStream outPrint;
    java.lang.Exception ex = null;
    try{ outPrint = newOutPrintWithAutoflushTurnedOff();
      try{ java.lang.System.setOut( outPrint ); }
      catch( final java.lang.SecurityException e ){ ex = e; }}
    catch( final java.lang.RuntimeException e ){ ex = e; }
    if( ex != null )throw new java.lang.RuntimeException( ex ); }

  public static void main( final java.lang.String[] args )
  { setOutWithAutoflushTurnedOff();
    java.lang.System.out.println( "Is autoflush\noff now?" ); }}