// /////////////////////////////////////////////////////////
// This file is part of Propel.
//
// Propel is free software: you can redistribute it and/or modify
// it under the terms of the GNU Lesser General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// Propel 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 Lesser General Public License for more details.
//
// You should have received a copy of the GNU Lesser General Public License
// along with Propel. If not, see <http://www.gnu.org/licenses/>.
// /////////////////////////////////////////////////////////
// Authored by: Nikolaos Tountas -> salam.kaser-at-gmail.com
// /////////////////////////////////////////////////////////
package propel.core.initialisation;
import lombok.Validate;
import lombok.Validate.NotNull;
import propel.core.threading.primitives.SharedFlag;
/**
* Thread-safe lock-free guard, allows components to check whether they have initialised prior to being used.
*/
public final class MultiInitGuard
implements InitGuard
{
// used for maintaining the state
private final SharedFlag flag;
// used to identify the owner of this guard
private final String className;
/**
* Constructor initialises with the owner of this guard
*
* @throws NullPointerException An argument is null
*/
@Validate
public MultiInitGuard(@NotNull final Class<?> owner)
{
this.className = owner.getSimpleName();
this.flag = new SharedFlag();
}
/**
* Constructor initialises with the owner of this guard
*
* @throws NullPointerException An argument is null
*/
@Validate
public MultiInitGuard(@NotNull final String className)
{
this.className = className;
this.flag = new SharedFlag();
}
/**
* Call to initialise, can be called multiple times
*/
@Override
public void initialise()
{
flag.set();
}
/**
* {@inheritDoc}
*/
@Override
public void uninitialise()
{
if (!flag.unSet())
throw new IllegalStateException("Cannot proceed with un-initialisation of " + className
+ " instance as it is not in an initialised state");
}
/**
* {@inheritDoc}
*/
@Override
public void assertInitialised()
{
if (flag.isNotSet())
throw new IllegalStateException("Instance of " + className + " is not in an initialised state");
}
/**
* {@inheritDoc}
*/
@Override
public void assertNotInitialised()
{
if (flag.isSet())
throw new IllegalStateException("Instance of " + className + " is in an initialised state");
}
/**
* {@inheritDoc}
*/
@Override
public boolean isInitialised()
{
return flag.isSet();
}
}