From 7a2e20caac9db6f789a7b3fab344b9758af45335 Mon Sep 17 00:00:00 2001 From: Harvey Harrison Date: Sun, 19 Apr 2015 21:02:06 -0700 Subject: j3dcore: flatten the directory structure a bit Signed-off-by: Harvey Harrison --- src/javax/media/j3d/GeometryLock.java | 85 +++++++++++++++++++++++++++++++++++ 1 file changed, 85 insertions(+) create mode 100644 src/javax/media/j3d/GeometryLock.java (limited to 'src/javax/media/j3d/GeometryLock.java') diff --git a/src/javax/media/j3d/GeometryLock.java b/src/javax/media/j3d/GeometryLock.java new file mode 100644 index 0000000..bb1132c --- /dev/null +++ b/src/javax/media/j3d/GeometryLock.java @@ -0,0 +1,85 @@ +/* + * Copyright 1999-2008 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 javax.media.j3d; + + +class GeometryLock { + + // Current thread holding the lock + Thread threadId = null; + + // Whether the lock is currently owned + boolean lockOwned = false; + + // Count > 1 , if there is nested lock by the same thread + int count = 0; + + // Number of outstanding threads waiting for the lock + int waiting = 0; + + + synchronized void getLock() { + Thread curThread = Thread.currentThread(); + // If the thread already has the lock, incr + // a count and return + if (threadId == curThread) { + count++; + return; + } + // Otherwise, wait until the lock is released + while (lockOwned) { + try { + waiting++; + wait(); + } catch (InterruptedException e) { + System.err.println(e); + } + waiting--; + } + count++; + // Acquire the lock + lockOwned = true; + threadId = curThread; + } + + synchronized void unLock() { + Thread curThread = Thread.currentThread(); + if (threadId == curThread) { + // If the lock count > 0, then return + if (--count > 0) { + return; + } + lockOwned = false; + threadId = null; + if (waiting > 0) { + notify(); + } + } + + } + +} -- cgit v1.2.3