OnJava8-Examples/newio/ChannelCopy.java
2016-09-23 13:23:35 -06:00

35 lines
1001 B
Java

// newio/ChannelCopy.java
// (c)2016 MindView LLC: see Copyright.txt
// We make no guarantees that this code is fit for any purpose.
// Visit http://OnJava8.com for more book information.
// Copying a file using channels and buffers
// {java ChannelCopy ChannelCopy.java test.txt}
import java.nio.*;
import java.nio.channels.*;
import java.io.*;
public class ChannelCopy {
private static final int BSIZE = 1024;
public static void
main(String[] args) throws Exception {
if(args.length != 2) {
System.out.println(
"arguments: sourcefile destfile");
System.exit(1);
}
try(
FileChannel in = new FileInputStream(
args[0]).getChannel();
FileChannel out = new FileOutputStream(
args[1]).getChannel()
) {
ByteBuffer buffer = ByteBuffer.allocate(BSIZE);
while(in.read(buffer) != -1) {
buffer.flip(); // Prepare for writing
out.write(buffer);
buffer.clear(); // Prepare for reading
}
}
}
}