question: public boolean doCheckSiteStatus ( URL url ) { if ( debug . messageEnabled ( ) ) { debug . message ( "SiteStatusCheckThreadImpl.doCheckSiteStatus: check " + url ) ; } URLChecker checker = getURLChecker ( url ) ; if ( checker != null && ( checker . getStatus ( ) == URLStatus . STATUS_UNKNOWN ) ) { synchronized ( checker ) { checker . cancel ( ) ; checker . notify ( ) ; } synchronized ( urlCheckers ) { urlCheckers . remove ( getThreadName ( url ) ) ; } debug . error ( "SiteStatusCheckThreadImpl.doCheckSiteStatus() " + "Killing thread " + getThreadName ( url ) ) ; return false ; } else if ( ( checker != null ) && ( checker . getStatus ( ) == URLStatus . STATUS_AVAILABLE ) ) { return true ; } else { return false ; } }
target:  The method that will be used by SiteMonitor to check each site is alive.