67 lines
1.5 KiB
Java
67 lines
1.5 KiB
Java
/*
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Copyright (C) 2002 Jeroen Frijters
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This software is provided 'as-is', without any express or implied
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warranty. In no event will the authors be held liable for any damages
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arising from the use of this software.
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Permission is granted to anyone to use this software for any purpose,
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including commercial applications, and to alter it and redistribute it
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freely, subject to the following restrictions:
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1. The origin of this software must not be misrepresented; you must not
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claim that you wrote the original software. If you use this software
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in a product, an acknowledgment in the product documentation would be
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appreciated but is not required.
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2. Altered source versions must be plainly marked as such, and must not be
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misrepresented as being the original software.
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3. This notice may not be removed or altered from any source distribution.
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Jeroen Frijters
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jeroen@frijters.net
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*/
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package sun.misc;
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import cli.System.WeakReference;
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public abstract class Ref
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{
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private WeakReference weakRef = new WeakReference(null);
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public Object get()
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{
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Object p = weakRef.get_Target();
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if(p == null)
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{
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synchronized(this)
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{
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if((p = weakRef.get_Target()) == null)
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{
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p = reconstitute();
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weakRef.set_Target(p);
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}
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}
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}
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return p;
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}
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public abstract Object reconstitute();
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public void flush()
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{
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weakRef.set_Target(null);
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}
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public void setThing(Object thing)
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{
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weakRef.set_Target(thing);
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}
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public Object check()
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{
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return weakRef.get_Target();
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}
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}
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