Standard concise way to copy a file in Java?

Tackling larger files with FileChannel

When dealing with larger files, consider using the FileChannel class that provides efficient methods to copy files, such as transferTo() and transferFrom().

import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.nio.channels.FileChannel;

// ...

try (FileChannel sourceChannel = new FileInputStream("source.txt").getChannel();
     FileChannel destChannel = new FileOutputStream("destination.txt").getChannel()) {

    destChannel.transferFrom(sourceChannel, 0, sourceChannel.size());
    // FileChannel: "Imma let you finish, but I am one of the BEST ways for copying files ever!"
}
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Just in case you forget, the snippet uses a try-with-resources block to automatically close the channels after usage, saving you the hassle of a "resource leaked" nightmare.

Handling complex copying scenarios

Starting from Java 7, you can use CopyOption parameters with Files.copy() method for managing different aspects of file copying. For example, copying file attributes or disregarding existing files:

import java.nio.file.*;

// ...

Files.copy(Paths.get("source.txt"), Paths.get("destination.txt"), 
           StandardCopyOption.COPY_ATTRIBUTES, LinkOption.NOFOLLOW_LINKS);
// CopyOption: "I carry a load of flexibility on my shoulders!"
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Creating custom copy operations

If you have custom requirements, like recursive directory copying, you can develop a FileVisitor implementing the FileVisitor interface provided by the Java NIO package.

// ...Your recursive copy operation goes here...
// Path walker: "I walk a lonely road, the only one that I have ever known..."
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Native over external libraries: reduce dependencies

With Java's capabilities, it's often unnecessary to include external libraries for file operations. Stick with the standard library, and keep your project lean.

// Standard library user: "Who needs an external library when I look this good?"
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Cross-platform file handling

java.nio.file offers OS-independent file manipulation. This means you only need to write your code once, and it works transparently across different operating systems.

// java.nio.file: "I'm like that cool friend who gets along with everyone!"
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Robust error handling

Make your file operations resilient. Infuse your code with the correct error-handling strategies by catching potentially occurring exceptions.

// Robust developer: "Expect the unexpected, handle your exceptions!"
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