今天貌似發(fā)現(xiàn)了一個java的bug.
這是一個內(nèi)部匿名類調(diào)用外部類方法的問題.
我在外部類中有個notifyAll(Object me)方法,在內(nèi)部匿名類里卻無法調(diào)用它，編譯報錯。
嘗試把notifyAll改名為tellAll，——恩，蠻好，可以調(diào)用。
嘗試寫成 OuterClassName.this.notifyAll(me)——恩，也可以調(diào)用。
看起來如果在外部類中重載Object的方法，java無法區(qū)分。

/**?*/ /**
?*?
? */
package ?cn.roob.webdown.statistic;

import ?java.util.concurrent.Executors;
import ?java.util.concurrent.ScheduledExecutorService;
import ?java.util.concurrent.TimeUnit;

import ?org.apache.log4j.Logger;

import ?cn.roob.webdown.persist.StatisticDAO;
import ?cn.roob.webdown.persist.TaskCountRecord;
import ?cn.roob.webdown.util.Config;

/**?*/ /**
?*?任務(wù)狀態(tài)定時統(tǒng)計線程,只記錄發(fā)生了變動的統(tǒng)計結(jié)果.<br>
?*?以單例模式運(yùn)行,通過觀察者模式發(fā)送統(tǒng)計結(jié)果<br>
?*?典型的觀察者有客戶端通訊和統(tǒng)計曲線圖
?*?
?*? @author ?tedeyang
?*?
? */
public ? class ?TaskStatistic? extends ?CommonStatisticSource? {
???? static ? private ? int ?statisticRate? = ?Config.getApplicationConfig().statisticRate();
???? static ? private ?TaskStatistic?thread? = ? null ;
???? private ? static ?Logger?log? = ?Logger.getLogger(TaskStatistic. class );
???? private ? final ?ScheduledExecutorService?schedule? = ?Executors.newSingleThreadScheduledExecutor();
???? private ? boolean ?started? = ? false ;

???? private ?TaskStatistic()? {
????}

???? public ? static ?TaskStatistic?getSingleScheduledThread()? {
???????? if ?(thread? == ? null )? {
????????????thread? = ? new ?TaskStatistic();
????????}
???????? return ?thread;
????}

???? /**?*/ /**
?????*?在垃圾收集前停止線程
?????*? @see ?java.lang.Object#finalize()
????? */
???? protected ? void ?finalize()? throws ?Throwable? {
???????? this .stop();
???????? super .finalize();
????}

???? /**?*/ /**
?????*?啟動,以固定的延遲頻率統(tǒng)計數(shù)據(jù)庫中任務(wù)的狀態(tài),如果狀態(tài)發(fā)生變化則通知監(jiān)聽者,并記錄.
????? */
???? public ? void ?start()? {
???????? if ?(started)
???????????? return ;
???????? if ?(log.isInfoEnabled())
????????????log.info( " 啟動任務(wù)統(tǒng)計線程 " );
????????started? = ? true ;

???????? final ?StatisticDAO?dao? = ? new ?StatisticDAO();
????????schedule.scheduleWithFixedDelay(
????????????????
???????????????? new ?Runnable()? {
????????????????????TaskCountRecord?lastRecord? = ? null ;
???????????????????? public ? void ?run()? {
????????????????????????TaskCountRecord?totalCount? = ?dao.countTaskStatus();
???????????????????????? // ?任務(wù)數(shù)沒有變化則不更新
???????????????????????? if ?( ! totalCount.equals(lastRecord))? {
????????????????????????????lastRecord? = ?totalCount;
????????????????????????????tellAllObservers(totalCount);
????????????????????????????dao.save(totalCount);?
????????????????????????????????notifyAll(totalCount);//該方法在父類中
????????????????????????} ?
????????????????????}
????????????????} ,
????????????????statisticRate,?
????????????????statisticRate,?
????????????????TimeUnit.SECONDS
????????);
????}

???? /**?*/ /**
?????*?結(jié)束
????? */
???? public ? void ?stop()? {
????????schedule.shutdown();
????????started? = ? false ;
???????? if ?(log.isInfoEnabled())
????????????log.info( " 停止任務(wù)統(tǒng)計線程 " );
????}
}