voidwaitForSignal(){Objectobj=newObject();synchronized(Thread.currentThread()){obj.wait();obj.notify();}}Whichistrue?() A.ThiscodemaythrowanInterruptedException.B.ThiscodemaythrowanIllegalStateException.C.ThiscodemaythrowaTimeoutExceptionaftertenminutes.D.Thiscodewillnotcompileunless“obj.wait（）”isreplacedwith“（（Thread）obj）.wait（）”.E.Reversingtheorderofobj.wait（）andobj.notify（）maycausethismethodtocompletenormally.F.Acalltonotify（）ornotifyAll（）fromanotherthreadmaycausethismethodtocompletenormally.
voidwaitForSignal(){Objectobj=newObject();synchronized(Thread.currentThread()){obj.wait();obj.notify();}}Whichistrue?()
A.ThiscodemaythrowanInterruptedException.
B.ThiscodemaythrowanIllegalStateException.
C.ThiscodemaythrowaTimeoutExceptionaftertenminutes.
D.Thiscodewillnotcompileunless“obj.wait（）”isreplacedwith“（（Thread）obj）.wait（）”.
E.Reversingtheorderofobj.wait（）andobj.notify（）maycausethismethodtocompletenormally.
F.Acalltonotify（）ornotifyAll（）fromanotherthreadmaycausethismethodtocompletenormally.
相关考题：
Whichthreewillcompileandrunwithoutexception?() A.privatesynchronizedObjecto；B.voidgo（）{synchronized（）{/*codehere*/}C.publicsynchronizedvoidgo（）{/*codehere*/}D.privatesynchronized（this）voidgo（）{/*codehere*/}E.voidgo（）{synchronized（Object.class）{/*codehere*/}F.voidgo（）{Objecto=newObject（）；synchronized（o）{/*codehere*/}
1.public class GC{2.private Objec to；3.private void doSomethingElse（Object obj）{o=obj；}4.public void doSomething（）{5.Object o=new Object（）；6.doSomethingElse（o）；7.o=new Object（）；8.doSomethingElse（null）；9.o=null；10.}11.}When the doSomething method is called，after which line does the Object created in line 5 become available for garbage collection？（）A.Line5B.Line6C.Line7D.Line8E.Line9F.Line10
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Whichthreewillcompileandrimwithoutexception?() A.privatesynchronizedObjecto；B.voidgo（）{synchronized（）{/*codehere*/}}C.publicsynchronizedvoidgo（）{/*codehere*/}D.privatesynchronized（this）voidgo（）{/*codehere*/}E.voidgo（）{synchronized（Object.class）{/*codehere*/}}F.voidgo（）{Objecto=newObject（）；synchronized（o）{/*codehere*/}}
publicclassTwoThreads{privatestaticObjectresource=newObject（）；privatestaticvoiddelay（longn）{try{Thread.sleep（n）；}catch（Exceptione）{System.out.print（”Error）；}}publicstaticvoidmain（String[]args）{System.out.print（”StartMain）；newThread1（）.start（）；delay（1000）；Threadt2=newThread2（）；t2.start（）；delay（1000）；t2.interruptdelay（1000）；System.out.print（”EndMain）；}staticclassThread1extendsThread{publicvoidrun（）{synchronized（resource）{System.out.print（”Startl）；delay（6000）；System.out.print（”End1）；}}}staticclassThread2extendsThread{publicvoidrun（）{synchronized（resource）{System.out.print（”Start2）；delay（2000）；System.out.print（”End2）；}}}}Assumethatsleep（n）executesinexactlymmilliseconds，andallothercodeexecutesinaninsignificantamountoftime.Whatistheoutputifthemain（）methodisrun？（）
publicstaticvoidmain(String[]args){12.Objectobj=newObject(){13.publicinthashCode(){14.returns42;15.}16.};17.System.out.println(obj.hashCode());18.}Whatistheresult?() A.42B.Anexceptionisthrownatruntime.C.Compilationfailsbecauseofanerroronline12.D.Compilationfailsbecauseofanerroronline16.E.Compilationfailsbecauseofanerroronline17.
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newObject为body对象的一级子节点，newObject.css（"display","block");将使得newObject可见。