NativeThread.java

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package sun.nio.ch;


// Signalling operations on native threads
//
// On some operating systems (e.g., Linux), closing a channel while another
// thread is blocked in an I/O operation upon that channel does not cause that
// thread to be released.  This class provides access to the native threads
// upon which Java threads are built, and defines a simple signal mechanism
// that can be used to release a native thread from a blocking I/O operation.
// On systems that do not require this type of signalling, the current() method
// always returns -1 and the signal(long) method has no effect.


public class NativeThread {

    // Returns an opaque token representing the native thread underlying the
    // invoking Java thread.  On systems that do not require signalling, this
    // method always returns -1.
    //
    public static native long current();

    // Signals the given native thread so as to release it from a blocking I/O
    // operation.  On systems that do not require signalling, this method has
    // no effect.
    //
    public static native void signal(long nt);

    private static native void init();

    static {
        IOUtil.load();
        init();
    }

}