Module jdk.net
Package jdk.nio

Class Channels


  • public final class Channels
    extends Object
    Defines static methods to create channels.

    Unless otherwise specified, passing a null argument to any of the methods defined here will cause a NullPointerException to be thrown.

    Since:
    11
    • Method Detail

      • readWriteSelectableChannel

        public static SelectableChannel readWriteSelectableChannel​(FileDescriptor fd,
                                                                   Channels.SelectableChannelCloser closer)
        Creates a selectable channel to a file descriptor that supports an operation-set of OP_READ and OP_WRITE. The selectable channel will be created by the default SelectorProvider.

        The given file descriptor is a socket or resource that can be multiplexed by a Selector for read and write readiness. Great care is required to coordinate direct use of the file descriptor with the use of the selectable channel. In particular, changing the blocking mode or closing the file descriptor without careful coordination will result in unspecified and unsafe side effects. The given SelectableChannelCloser is invoked to close the file descriptor and to coordinate the closing when the channel is registered with a Selector.

        If there is a security manager set then its checkRead and checkWrite methods are invoked to check that the caller has permission to both read from and write to the file descriptor.

        Implementation Note:
        This method throws UnsupportedOperationException if the default SelectorProvider is not the JDK built-in implementation.
        Parameters:
        fd - The file descriptor
        closer - The object to close the channel
        Returns:
        The selectable channel
        Throws:
        IllegalArgumentException - If the file descriptor is not valid
        SecurityException - If denied by the security manager