--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/jdk/src/share/classes/sun/nio/ch/NativeThreadSet.java	Sat Dec 01 00:00:00 2007 +0000
@@ -0,0 +1,98 @@
+/*
+ * Copyright 2002-2006 Sun Microsystems, Inc.  All Rights Reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.  Sun designates this
+ * particular file as subject to the "Classpath" exception as provided
+ * by Sun 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).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
+ * CA 95054 USA or visit www.sun.com if you need additional information or
+ * have any questions.
+ */
+
+package sun.nio.ch;
+
+
+// Special-purpose data structure for sets of native threads
+
+
+class NativeThreadSet {
+
+    private long[] elts;
+    private int used = 0;
+
+    NativeThreadSet(int n) {
+        elts = new long[n];
+    }
+
+    // Adds the current native thread to this set, returning its index so that
+    // it can efficiently be removed later.
+    //
+    int add() {
+        long th = NativeThread.current();
+        if (th <= 0)
+            return -1;
+        synchronized (this) {
+            int start = 0;
+            if (used >= elts.length) {
+                int on = elts.length;
+                int nn = on * 2;
+                long[] nelts = new long[nn];
+                System.arraycopy(elts, 0, nelts, 0, on);
+                elts = nelts;
+                start = on;
+            }
+            for (int i = start; i < elts.length; i++) {
+                if (elts[i] == 0) {
+                    elts[i] = th;
+                    used++;
+                    return i;
+                }
+            }
+            assert false;
+            return -1;
+        }
+    }
+
+    // Removes the thread at the given index.
+    //
+    void remove(int i) {
+        if (i < 0)
+            return;
+        synchronized (this) {
+            elts[i] = 0;
+            used--;
+        }
+    }
+
+    // Signals all threads in this set.
+    //
+    void signal() {
+        synchronized (this) {
+            int u = used;
+            int n = elts.length;
+            for (int i = 0; i < n; i++) {
+                long th = elts[i];
+                if (th == 0)
+                    continue;
+                NativeThread.signal(th);
+                if (--u == 0)
+                    break;
+            }
+        }
+    }
+
+}