FileChannel class

[Sue Nair]

I am trying to finish up a homework assignment and I am having a little bit of trouble. I am using the FileChannel class to copy input from one file to another. My program will compile but I am not for sure what else to do? I think my problem is in creating a file to be copied. I have created a folder sDir and put in a file.Is this all I need to do? I am not for sure how to have my program create the tDir and copy the contents of sDir. Could someone please look at my code and help me?

 
package CH3HW.lab1;
 
import java.io.*;
import java.nio.channels.FileChannel;
 
public class FileCopy
{
private static void copyDir(String sDir, String tDir) throws IOException
{
File targetDir=new File(tDir);
if(targetDir.exists());
{
System.out.println("Creating"+targetDir.getPath());
targetDir.mkdirs();
}
}
private static void copyFile(File toBeCopied, File newCopy) throws IOException
{
FileInputStream fis=new FileInputStream(toBeCopied);
FileChannel fcin=fis.getChannel();
FileOutputStream fos=new FileOutputStream(newCopy);
FileChannel fcout=fos.getChannel();
 
fcin.transferTo(0, fcin.size(),fcout);
 
fcin.close();
fcout.close();
fis.close();
fos.close();
}
 
public static void main(String[] args) throws IOException
{
File sourceFile=new File("sDir");
String sDir="sDir";
String[]files=sourceFile.list();
File newPath=new File("tDir");
String tDir="tDir";
 
for(int i=0;i<files.length;i++)
{
File toBeCopied=new File(sourceFile + "\\" + files[i]);
File newCopy=new File(newPath + "\\" + files[i]);
System.out.println("Copying file" +files[i]);
copyDir(sDir,tDir);
copyFile(toBeCopied,newCopy);
}
}
}

Thanks
[ February 24, 2008: Message edited by: Jim Yingst ]

[Balasubramanian Chandrasekaran]

Have you tried your code.It looks like the code you have written does what you need.

[Rob Spoor]

if (targetDir.exists());
{
    System.out.println("Creating"+targetDir.getPath());
    targetDir.mkdirs();
}

I think you have made a logical mistake here, which happens to be solved by a syntactical mistake.

You should add a ! before targetDir - you want to create the folder if it doesn't exist, not if it already exists.

Now your code still works because of the ; right after the if. Right now, your code is equal to this:

if (targetDir.exists())
{
    // empty statement here
}
System.out.println("Creating"+targetDir.getPath());
targetDir.mkdirs();

So if you add the ! and remove the ; you should be fine:

if (!targetDir.exists())
{
    System.out.println("Creating"+targetDir.getPath());
    targetDir.mkdirs();
}

[Sue Nair]

Thank you! It does work now.