/**
*
* Copyright (c) 2014, the Railo Company Ltd. All rights reserved.
*
* This library 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 2.1 of the License, or (at your option) any later version.
*
* This library 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 this library. If not, see <http://www.gnu.org/licenses/>.
*
**/
package lucee.commons.lang.lock;
public final class KeyLock {
private final Token token=new Token();
private KeyLockListener listener;
public KeyLock() {
this.listener=NullKeyLockListener.getInstance();
}
public KeyLock(KeyLockListener listener) {
this.listener=listener;
}
public void start(String key) {
while(true) {
// nobody inside
synchronized(token) {
if(token.value==null) {
token.value=key;
token.count++;
listener.onStart(token.value,true);
return;
}
if(key.equalsIgnoreCase(token.value)) {
token.count++;
listener.onStart(token.value,false);
return;
}
try {
token.wait();
}
catch (InterruptedException e) {}
}
}
}
public void end() {
synchronized(token) {
if(--token.count<=0) {
listener.onEnd(token.value,true);
if(token.count<0)token.count=0;
token.value=null;
}
else listener.onEnd(token.value,false);
token.notify();
}
}
public void setListener(KeyLockListener listener) {
this.listener=listener;
}
}
class Token {
int count=0;
String value=null;
}