ojluni/src/main/java/sun/nio/ch/NativeThread.java

/*
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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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 * published by the Free Software Foundation.  Oracle designates this
 * particular file as subject to the "Classpath" exception as provided
 * by Oracle in the LICENSE file that accompanied this code.
 *
 * This code is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
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 * 2 along with this work; if not, write to the Free Software Foundation,
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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.


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.
    //
    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.
    //
    static native void signal(long nt);

    static native void init();

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

}