publicclassSyncTest{privateintx；privateinty；publicsynchronizedvoidsetX（inti）（x=1；）publicsynchronizedvoidsetY（inti）（y=1；）publicsynchronizedvoidsetXY（int1）（setX（i）；setY（i）；）publicsynchronizedBooleancheck（）（returnx!=y；）}Underwhichconditionswillcheck（）returntruewhencalledfromadifferentclass？A.Check（）canneverreturntrue.B.Check（）canreturntruewhensetXYiscalledbymultiplethreads.C.Check（）canreturntruewhenmultiplethreadscallsetXandsetYseparately.D.Check（）canonlyreturntrueifSyncTestischangedtoallowxandytobesetseparately.
publicclassSyncTest{privateintx；privateinty；publicsynchronizedvoidsetX（inti）（x=1；）publicsynchronizedvoidsetY（inti）（y=1；）publicsynchronizedvoidsetXY（int1）（setX（i）；setY（i）；）publicsynchronizedBooleancheck（）（returnx!=y；）}Underwhichconditionswillcheck（）returntruewhencalledfromadifferentclass？
A.Check（）canneverreturntrue.
B.Check（）canreturntruewhensetXYiscalledbymultiplethreads.
C.Check（）canreturntruewhenmultiplethreadscallsetXandsetYseparately.
D.Check（）canonlyreturntrueifSyncTestischangedtoallowxandytobesetseparately.
相关考题：
（ 18 ）阅读下列程序Public class Test implements Runnable{Private int x=0;Private int y=o;boolean flag=true;Public static void main(string[ ] args) {Test r =new Test( );Thead t1=new Thead(r);Thead t2=new Thead(r);t1.start( );t2.start( );}Public void run(){While(flag) {x++;y++;system.out.println( “ ( ” +x_ “ , ” +y+ ” ) ” );if (x=10)flag=false;}}}下列对程序运行结果描述的选项中，正确的是Ａ）每行的（ x,y ）中，可能有；每一对（ x,y ）值都出现两次。Ｂ）每行的（ x,y ）中，可能有；每一对（ x,y ）值仅出现一次。Ｃ）每行的（ x,y ）中，可能有 x=y ；每一对（ x,y ）值都出现两次。Ｄ）每行的（ x,y ）中，可能有 x=y ；每一对（ x,y ）值都出现一次。
publicclassTestFive{privateintx；publicvoidfoo（）{intcurrent=x；x=current+1；}publicvoidgo（）{for（inti=0；i5；i++）{newThread（）{publicvoidrun（）{foo（）；System.out.print（x+，）；}}.start（）；}}}Whichtwochanges，takentogether，wouldguaranteetheoutput：1，2，3，4，5，？（）A.Movetheline12printstatementintothefoo（）method.B.Changeline7topublicsynchronizedvoidgo（）{.C.Changethevariabledeclarationonline3toprivatevolatileintx；.D.Wrapthecodeinsidethefoo（）methodwithasynchronized（this）block.E.Wraptheforloopcodeinsidethego（）methodwithasynchronizedblocksynchronized（this）{//forloopcodehere}.
publicabstractclassShape{privateintx;privateinty;publicabstractvoiddraw();publicvoidsetAnchor(intx,inty){this.x=x;this.y=y;}}WhichtwoclassesusetheShapeclasscorrectly?() A.publicclassCircleimplementsShape{privateintradius；}B.publicabstractclassCircleextendsShape{privateintradius；}C.publicclassCircleextendsShape{privateintradius；publicvoiddraw（）；}D.publicabstractclassCircleimplementsShape{privateintradius；publicvoiddraw（）；}E.publicclassCircleextendsShape{privateintradius；publicvoiddraw（）{/*codehere*/}}F.publicabstractclassCircleimplementsShape{privateintradius；publicvoiddraw（）{/codehere*/}}
1.publicclassXimplementsRunnable（2.privateintx；3.privateinty；4.5.publicstaticvoidmain（String[]args）6.Xthat=newX（）；7.（newThread（that））.start（）；8.（newThread（that））.start（）；9.）10.11.publicvoidrun（）（12.for（；；）（13.x++；14.y++；15.System.out.printIn（x=”+x+，y=”+y）；16.）17.）Whatistheresult？（）A.Errorsatlines7and8causecompilationtofail.B.Theprogramprintspairsofvaluesforxandythatmightnotalwaysbethesameonthesameline（forexample，“x=2，y=1”）.C.Theprogramprintspairsofvaluesforxandythatarealwaysthesameonthesameline（forexample，“x=1，y=1”.Inaddition，eachvalueappearstwice（forexample，“x=1，y=1”followedby“x=1，y=1”）.D.Theprogramprintspairsofvaluesforxandythatarealwaysthesameonthesameline（forexample，“x=1，y=1”.Inaddition，eachvalueappearsonlyforonce（forexample，“x=1，y=1”followedby“x=2，y=2”）.
publicclassXimplementsRunnable（privateintx；privateinty；publicstaticvoidmain（String[]args）（Xthat=newX（）；（newThread（that））.start（）；（newThread（that））.start（）；）publicsynchronizedvoidrun（）（for（；；）（x++；y++；System.out.printIn（x=+x+，y=+y）；）））Whatistheresult？（）A.Anerroratline11causescompilationtofail.B.Errorsatlines7and8causecompilationtofail.C.Theprogramprintspairsofvaluesforxandythatmightnotalwaysbethesameonthesameline（forexample，“x=2，y=1”）D.Theprogramprintspairsofvaluesforxandythatarealwaysthesameonthesameline（forexample，“x=1，y=1”.Inaddition，eachvalueappearstwice（forexample，“x=1，y=1”followedby“x=1，y=1”）E.Theprogramprintspairsofvaluesforxandythatarealwaysthesameonthesameline（forexample，“x=1，y=1”.Inaddition，eachvalueappearstwice（forexample，“x=1，y=1”followedby“x=2s，y=2”）
publicclassSyncTest（privateintx；privateinty；privatesynchronizedvoidsetX（inti）（x=1；）privatesynchronizedvoidsetY（inti）（y=1；）publicvoidsetXY（int1）（setX（i）；setY（i）；）publicsynchronizedBooleancheck（）（returnx!=y；））Underwhichconditionswillcheck（）returntruewhencalledfromadifferentclass？A.Check（）canneverreturntrue.B.Check（）canreturntruewhensetXYiscalledbymultiplethreads.C.Check（）canreturntruewhenmultiplethreadscallsetXandsetYseparately.D.Check（）canonlyreturntrueifSyncTestischangedtoallowxandytobesetseparately.
publicclassXimplementsRunnable{privateintx；privateinty；publicstaticvoidmain（String[]args）{Xthat=newX（）；（newThread（that））.start（）；（newThread（that））.start（）；}publicvoidrun（）{for（；；）{synchronized（this）{x++；y++；}System.out.println（Thread.currentThread（）.getName（）+x=+x+，y=+y）；}}}Whatistheresult？（）A.Compilationfails.B.Theprogramprintspairsofvaluesforxandythatmightnotalwaysbethesameonthesameline（forexample，“x=2，y=1”）.C.Theprogramprintspairsofvaluesforxandythatarealwaysthesameonthesameline（forexample，“x=1，y=1”）. Inaddition，eachvalueappearsonlyonce（forexample，“x=1，y=1”followedby“x=2，y=2”）. Thethreadnameatthestartofthelineshowsthatboththreadsareexecutingconcurrently.D.Theprogramprintspairsofvaluesforxandythatarealwaysthesameonthesameline（forexample，“x=1，y=1”）. Inaddition，eachvalueappearsonlyonce（forexample，“x=1，y=1”followedby“x=2，y=2”）. Thethreadnameatthestartofthelineshowsthatonlyasinglethreadisactuallyexecuting.
publicclassSyncTest{privateintx；privateinty；privatesynchronizedvoidsetX（inti）{x=i；}privatesynchronizedvoidsetY（inti）{y=i；}publicvoidsetXY（inti）{setX（i）；setY（i）；}publicsynchronizedbooleancheck（）{returnx!=y；}}Underwhichconditionwillcheckreturntruewhencalledfromadifferentclass？（）A.checkcanneverreturntrue.B.checkcanreturntruewhensetXYiscalledbymultiplethreads.C.checkcanreturntruewhenmultiplethreadscallsetXandsetYseparately.D.checkcanreturntrueonlyifSyncTestischangedtoallowxandytobesetseparately.
publicclassXimplementsRunnable（privateintx；privateinty；publicstaticvoidmain（Stringargs）（Xthat=newX（）；（newThread（that））.start（）；（newThread（that））.start（）；）publicsynchronizedvoidrun（）（for（；；）（x++；y++；System.out.printIn（x=+x+，y=+y）；）））Whatistheresult？（）A.Anerroratline11causescompilationtofail.B.Errorsatlines7and8causecompilationtofail.C.Theprogramprintspairsofvaluesforxandythatmightnotalwaysbethesameonthesameline（forexample，“x=2，y=1”）D.Theprogramprintspairsofvaluesforxandythatarealwaysthesameonthesameline（forexample，“x=1，y=1”.Inaddition，eachvalueappearstwice（forexample，“x=1，y=1”followedby“x=1，y=1”）E.Theprogramprintspairsofvaluesforxandythatarealwaysthesameonthesameline（forexample，“x=1，y=1”.Inaddition，eachvalueappearstwice（forexample，“x=1，y=1”followedby“x=2s，y=2”）