Why Channel interface redefine close() method?

Question

The close() method has already defined in the Closeable interface, why Channel redefines it again?

package java.io;
import java.io.IOException;

public interface Closeable extends AutoCloseable {
    public void close() throws IOException;
}

package java.nio.channels;

import java.io.IOException;
import java.io.Closeable;

public interface Channel extends Closeable {

    public boolean isOpen();

    public void close() throws IOException;

}

Possibly just for clarity and readability, but you'd have to ask whomever at Oracle wrote that line. — , Jul 21 '20 at 08:53

Polygnome · Accepted Answer · 2020-07-21T13:21:09.117

You have unfortunately not copied the most important parts - the JavaDoc.

The JavaDoc of Channel#close() clarifies quite a bit of the channel-specific details for this method, for example that subsequent operations throw ClosedChannelException, and how this method behaves when multiple threads are involved, especially blocking behavior.

_{Also, Channel predates Closeable (introduced in 1.4, Closeable in 1.5) and was retrofitted with that interface.}

Why Channel interface redefine close() method?

1 Answers1