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// **********************************************************************
//
// Copyright (c) 2001
// Mutable Realms, Inc.
// Huntsville, AL, USA
//
// All Rights Reserved
//
// **********************************************************************
package IceInternal;
public class RecursiveMutex
{
public
RecursiveMutex()
{
_owner = null;
_locked = false;
_count = 0;
}
public synchronized void
lock()
{
if(_locked && Thread.currentThread() == _owner)
{
_count++;
return;
}
while(_locked)
{
try
{
wait();
}
catch(InterruptedException ex)
{
}
}
assert(_owner == null && _count == 0);
_locked = true;
_owner = Thread.currentThread();
_count = 1;
}
public synchronized boolean
trylock()
{
if(_owner == null)
{
_owner = Thread.currentThread();
_count = 1;
_locked = true;
return true;
}
if(_owner == Thread.currentThread())
{
assert(_count > 0);
_count++;
return true;
}
return false;
}
public synchronized void
unlock()
{
assert(_owner == Thread.currentThread() && _count > 0 && _locked);
_count--;
if(_count <= 0)
{
_locked = false;
_owner = null;
notify();
}
}
private Thread _owner;
private boolean _locked;
private int _count;
}
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