throttleduseandtimeoutexpirationpolicy.java

来自「CAS在Tomcat中实现单点登录项目,单点登录（Single Sign On 」· Java 代码 · 共 72 行

/*
 * Copyright 2007 The JA-SIG Collaborative. All rights reserved. See license
 * distributed with this file and available online at
 * http://www.ja-sig.org/products/cas/overview/license/
 */
package org.jasig.cas.ticket.support;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.jasig.cas.ticket.ExpirationPolicy;
import org.jasig.cas.ticket.TicketState;

/**
 * Implementation of an expiration policy that adds the concept of saying that a
 * ticket can only be used once every X millseconds to prevent misconfigured
 * clients from consuming resources by doing constant redirects.
 * 
 * @author Scott Battaglia
 * @version $Revision: 42053 $ $Date: 2007-06-10 09:17:55 -0400 (Sun, 10 Jun 2007) $
 * @since 3.0.5
 */
public final class ThrottledUseAndTimeoutExpirationPolicy implements
    ExpirationPolicy {

    private Log log = LogFactory.getLog(this.getClass());

    /** Static ID for serialization. */
    private static final long serialVersionUID = -848036845536731268L;

    /** The time to kill in milliseconds. */
    private long timeToKillInMilliSeconds;

    /** Time time between which a ticket must wait to be used again. */
    private long timeInBetweenUsesInMilliSeconds;

    public void setTimeInBetweenUsesInMilliSeconds(
        final long timeInBetweenUsesInMilliSeconds) {
        this.timeInBetweenUsesInMilliSeconds = timeInBetweenUsesInMilliSeconds;
    }

    public void setTimeToKillInMilliSeconds(final long timeToKillInMilliSeconds) {
        this.timeToKillInMilliSeconds = timeToKillInMilliSeconds;
    }

    public boolean isExpired(final TicketState ticketState) {
        if (ticketState.getCountOfUses() == 0
            && (System.currentTimeMillis() - ticketState.getLastTimeUsed() < this.timeToKillInMilliSeconds)) {
            if (log.isDebugEnabled()) {
                log
                    .debug("Ticket is not expired due to a count of zero and the time being less than the timeToKillInMilliseconds");
            }
            return false;
        }

        if ((System.currentTimeMillis() - ticketState.getLastTimeUsed() >= this.timeToKillInMilliSeconds)) {
            if (log.isDebugEnabled()) {
                log
                    .debug("Ticket is expired due to the time being greater than the timeToKillInMilliseconds");
            }
            return true;
        }

        if ((System.currentTimeMillis() - ticketState.getLastTimeUsed() <= this.timeInBetweenUsesInMilliSeconds)) {
            log
                .warn("Ticket is expired due to the time being less than the waiting period.");
            return true;
        }

        return false;
    }
}