You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
106 lines
4.2 KiB
106 lines
4.2 KiB
// kelondroLock.java
|
|
// -----------------------
|
|
// part of YaCy
|
|
// (C) by Michael Peter Christen; mc@anomic.de
|
|
// first published on http://www.anomic.de
|
|
// Frankfurt, Germany, 2005
|
|
// Created 08.12.2005
|
|
//
|
|
// This program is free software; you can redistribute it and/or modify
|
|
// it under the terms of the GNU General Public License as published by
|
|
// the Free Software Foundation; either version 2 of the License, or
|
|
// (at your option) any later version.
|
|
//
|
|
// This program 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 for more details.
|
|
//
|
|
// You should have received a copy of the GNU General Public License
|
|
// along with this program; if not, write to the Free Software
|
|
// Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
|
|
//
|
|
// Using this software in any meaning (reading, learning, copying, compiling,
|
|
// running) means that you agree that the Author(s) is (are) not responsible
|
|
// for cost, loss of data or any harm that may be caused directly or indirectly
|
|
// by usage of this softare or this documentation. The usage of this software
|
|
// is on your own risk. The installation and usage (starting/running) of this
|
|
// software may allow other people or application to access your computer and
|
|
// any attached devices and is highly dependent on the configuration of the
|
|
// software which must be done by the user of the software; the author(s) is
|
|
// (are) also not responsible for proper configuration and usage of the
|
|
// software, even if provoked by documentation provided together with
|
|
// the software.
|
|
//
|
|
// Any changes to this file according to the GPL as documented in the file
|
|
// gpl.txt aside this file in the shipment you received can be done to the
|
|
// lines that follows this copyright notice here, but changes must not be
|
|
// done inside the copyright notive above. A re-distribution must contain
|
|
// the intact and unchanged copyright notice.
|
|
// Contributions and changes to the program code must be marked as such.
|
|
|
|
package de.anomic.kelondro;
|
|
|
|
public class kelondroLock {
|
|
|
|
private boolean lock;
|
|
private long releaseTime;
|
|
|
|
public kelondroLock() {
|
|
lock = false;
|
|
releaseTime = 0;
|
|
}
|
|
|
|
public synchronized void apply() {
|
|
// this applies a lock to this objekt
|
|
// if the lock is already applied
|
|
// this object waits until it is released and applies it then again
|
|
// before it returns
|
|
apply(-1);
|
|
}
|
|
|
|
public synchronized void apply(long millis) {
|
|
// sets a lock that is valid for a specific time
|
|
// if the time is over, the lock is released automatically
|
|
if (locked()) {
|
|
do {
|
|
try { wait(100); }
|
|
catch (InterruptedException e) { }
|
|
catch (Exception e) { e.printStackTrace(); }
|
|
} while (locked());
|
|
}
|
|
lock = true;
|
|
releaseTime = (millis < 0) ? Long.MAX_VALUE : System.currentTimeMillis() + millis;
|
|
}
|
|
|
|
public synchronized boolean stay(long waitMillis, long lockMillis) {
|
|
// this tries to apply a lock, but does not block infinitely until
|
|
// the lock is released. If after the given time the lock is not released
|
|
// the method returns with false and no more lock is applied
|
|
// if the lock was applied successfully, it returns with true
|
|
if (locked()) {
|
|
try { wait(waitMillis); }
|
|
catch (InterruptedException e) { }
|
|
catch (Exception e) { e.printStackTrace(); }
|
|
if (locked()) return false;
|
|
}
|
|
lock = true;
|
|
releaseTime = (lockMillis < 0) ? Long.MAX_VALUE : System.currentTimeMillis() + lockMillis;
|
|
return true;
|
|
}
|
|
|
|
public synchronized void release() {
|
|
// this must be called to releas the lock to the object
|
|
// if it is not released, possibly all other tasks are blocked
|
|
if (locked()) {
|
|
lock = false;
|
|
releaseTime = 0;
|
|
notifyAll();
|
|
}
|
|
}
|
|
|
|
public synchronized boolean locked() {
|
|
return lock && (System.currentTimeMillis() < releaseTime);
|
|
}
|
|
}
|