Hello,

I want to make simple batch file that copies log file and then adds original file's modification date and run program.
I remember some time ago i was doing something like printing only chosen characters from command's result with +X -Y (from X to Y, or something very similar) but i totally forgotten how exactly and where should i use it.

In that case i would like to use 1-10, 13-14 and 16-17 characters (which should be date and time) of "dir ./debug.html" result Code: [Select]import java.io.*;
import java.util.Date;
import java.text.SimpleDateFormat;
import java.text.Format;

public class CopyFileWithModification {
    public static void main(String[] args){
        if (args.length != 1){
            System.out.printf("Usage: java CopyFileWithModification <file name>\n");
            System.exit(1);
        }
        File fileName = new File(args[0]);
        if ( fileName.exists() && fileName.isFile() ){
            long t = fileName.lastModified() ;
            Format dateFormatter = new SimpleDateFormat("yyyy-MM-dd-hh-mm-ss");
            String newFileName = fileName + "_" + dateFormatter.format( new Date(t) ) ;
            copyFile( args[0] , newFileName) ;
        }
    }
    public static int copyFile( String src, String dest ){
          File inputFile = new File(src);
          File outputFile = new File(dest);
          try {
            FILEREADER in = new FileReader(inputFile);
            FileWriter out = new FileWriter(outputFile);
            int ch;
            while ( (ch = in.read() ) != -1) out.write(ch);
            out.close();
            in.close();
            return 0;
          }catch (IOException ex ){
            ex.printStackTrace();
            return 1;
          }
    }
}


[recovering disk space - old attachment deleted by admin]Wow, copying a file a single byte at a time. That's EFFICIENT. I MEAN it would work here, but on the other hand, java!=batch so it doesn't really meet their needs.





Code: [Select]echo off
REM copylog <source> <destination>
copy %1 %2
echo %date% %time% >> %2

Quote from: BC_Programmer on December 24, 2010, 05:36:31 PM

Wow, copying a file a single byte at a time. That's efficient. I mean it would work here, but on the other hand, java!=batch so it doesn't really meet their needs.

Code: [Select]echo off
REM copylog <source> <destination>
copy %1 %2
echo %date% %time% >> %2

true , java is not batch. However, put the java statement inside a text file, name it with extension .bat, and its called a batch. !

are you serious? you are appending the current date time to the destination file contents. don't think its what OP wants.

java statements don't work in text files. and you cannot pass a .java file with the java or javaw executables. now if you use the compiled version, that would work, so one would need to either compile the provided java code using javac from the JDK (which of course requires downloading the JDK) download and use the attached class file (which requires trust of the poster that the .class is actually the compiled equivalent of the .java provided, not that there is any reason to think otherwise) and so forth. All this for a rather inefficient solution (well, ok, so the copy can easily just be replaced with a more appropriate java.nio implementation that uses chunks)

All this for a rather inefficient solution

Whenever such a statement is mentioned about inefficiency, its better to provide a benchmark to prove what you said is correct ( as pertaining to this particular case). Otherwise, its better not to assume that one thing is better than the other.

I don't need a benchmark. Copying a file a single byte at a time will be slower then copying it in larger chunks. It's common sense.

Thats not way i remember i was doing