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1Z0-809PDF
Oracle 1Z0-809 PDF is available.
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This is a sample demo for 1Z0-809:
Q1.Considerthefollowingclass.
1. publicfinalclassProgram{2. 3. finalprivateStringname;4. 5. Program(Stringname){6. this.name=name;7. 8. getName();9. }10. 11. //codehere 12. }
Whichofthefollowingcodewillmakeaninstanceofthisclassimmutable.
A. publicStringgetName(){returnname;}
B. publicStringgetName(Stringvalue){name=value;returnvalue;}
C. privateStringgetName(){returnname+"a";}
D. publicfinalStringgetName(){returnname+="a";}
E. AllofAbove.
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OptionA,Carecorrect.
OptionBandDhaveacompileerrorsincenamevariableisfinal.
OptionCisprivateanddoesn'tchangethenamevalue.
OptionAispublicanddoesn'tchangethenamevalue.
Examobjective:EncapsulationandSubclassing-Makingclassesimmutable.
OracleReference:https://docs.oracle.com/javase/tutorial/essential/concurrency/imstrat.html
https://www.certification-questions.com/
Q2.Considerthefollowingcode:
1. classSuperClass{2. protectedvoidmethod1(){3. System.out.print("MSuperC");4. }5. }6. 7. classSubClassextendsSuperClass{8. privatevoidmethod1(){9. System.out.print("MSubC");10. }11. 12. publicstaticvoidmain(String[]args){13. SubClasssc=newSubClass();14. sc.method1();15. }16. }
Whatwillbetheresult?
F. MSubC.
G. MSuperC.
H. MSuperCMSubC.
I. Compilationfails.
Noneofabove.
OptionDiscorrect.
Thecodefailstocompileatline8,cannotreducethevisibilityoftheinheritedmethodfromSuperClass.
Examobjective:EncapsulationandSubclassing-CreatinganduseJavasubclasses.
OracleReference:https://docs.oracle.com/javase/tutorial/java/IandI/subclasses.html
https://www.certification-questions.com/
Q3.Giventhefollowingclass:
1. publicclassTest{2. publicstaticvoidmain(Stringargs[]){3. //CodeHere4. Threadthread=newThread(r);5. thread.start();6. }7. }
WhichofthefollowinglineswillgiveavalidThreadcreation:
A. Threadr=()->System.out.println("Running");
B. Runr=()->System.out.println("Running");
C. Runnabler=()->System.out.println("Running");
D. Executabler=()->System.out.println("Running");
E. NoneOfAbove
OptionCiscorrect.
OptionA,B,andDareincorrecttheyarenotfunctionalinterface,soCistheonlyvalidoption.
Examobjective:Concurrency-CreatingworkerthreadsusingRunnableandCallable.
OracleReference:https://docs.oracle.com/javase/tutorial/essential/concurrency/
https://www.certification-questions.com/
Q4whichofthefollowingdatabaseurlarecorrect:
A. jdbc:mysql://localhost:3306
B. jdbc:mysql://localhost:3306/sample
C. jdbc:mysql://localhost:3306/sample/user=root?password=secret
D. jdbc:mysql://localhost:3306/sample?user=root&password=secret
E. All
OptionA,BandDarecorrect.
Thecorrecturlformatisthefollowing:
jdbc:mysql://[host][,failoverhost...]
[:port]/[database]
[?propertyName1][=propertyValue1]
[&propertyName2][=propertyValue2]...
SoCisincorrectandA,BandDarecorrect.
Examobjective:DatabaseApplicationswithJDBC-ConnectingtoadatabasebyusingaJDBCdriver.
OracleReference:https://docs.oracle.com/javase/tutorial/jdbc/overview/
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Q5.Giventhefollowingcode:
1. publicclassProgram{2. 3. publicstaticvoidmain(Stringargs[])throwsIOException{4. Consolec=System.console();5. inti=(int)c.readLine("Entervalue:");6. for(intj=0;j<i;j++){7. c.format("%2d",j);8. }9. }10. }
Whatwillbetheresultenteringthevalues5?
F. 12345
A. 01234
B. 02468
C. Thecodewillnotcompilebecauseofline5.
D. UnhandledexceptiontypeNumberFormatExceptionalline7.
OptionDiscorrect.
Themethodsignature"intreadLine(Stringfmt,Object...args)"doesn'texist,
therightmethodreturnaStringsoline5willgiveacompileerrorandoptionDisright.
Examobjective:I/OFundamentals-Readandwritedatafromtheconsole
OracleReference:https://docs.oracle.com/javase/tutorial/essential/io/cl.html
https://www.certification-questions.com/
Q6.Given
11. classSingleton{12. privateintcount=0;13. privateSingleton(){};14. publicstaticfinalSingletongetInstance(){returnnewSingleton();};15. publicvoidadd(inti){count+=i;};16. publicintgetCount(){returncount;};17. }18. 19. publicclassProgram{20. publicstaticvoidmain(String[]args){21. Singletons1=Singleton.getInstance();22. s1.add(3);23. Singletons2=Singleton.getInstance();24. s2.add(2);25. Singletons3=Singleton.getInstance();26. s2.add(1);27. System.out.println(s1.getCount()+s2.getCount()+s3.getCount());28. }29. }
Whatwillbetheresult?
A. 18
B. 7
C. 6
D. Thecodewillnotcompile.
E. Noneofabove
OptionCiscorrect.
Theclass"Singleton"isnotarealsingletonclass,infactateachmethodinvocation"getInstance()"anewobjectiscreated,andsos1,s2,s3countinstancevariableare3,2,1andthenoptionCiscorrect.
Examobjective:JavaClassDesign-Createandusesingletonclassesandimmutableclasses
OracleReference:https://docs.oracle.com/javase/tutorial/essential/concurrency/imstrat.html
https://www.certification-questions.com/
Q7.Given
1. publicclassProgram{2. 3. publicstaticvoidmain(String[]args){4. 5. List<Integer>list=Arrays.asList(4,6,12,66,3);6. 7. Strings=list.stream().map(i->{8. return""+(i+1);9. }).reduce("",String::concat);10. 11. System.out.println(s);12. }13. }
Whatwillbetheresult?
A. 4612663
B. 5713674
C. 3661264
D. Thecodewillnotcompilebecauseofline7.
E. UnhandledexceptiontypeNumberFormatExceptionalline8.
OptionBiscorrect.
TheProgramisapplyingamapfunctiontothestreamgeneratedfromlist.ForeachIntegerelement"i"thefunctionreturnanewStringwithvaluei+1.ThestreamisthenreducedtoaStringbytheconcatenationfunction"String::concat".SoOptionBiscorrect,andA,C,D,Eareincorrect.
Examobjective:CollectionsStreams,andFilters-Iteratingthroughacollectionusinglambdasyntax
OracleReference:https://docs.oracle.com/javase/8/docs/api/java/util/stream/package-summary.html
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Q8.WhichofthefollowingarecorrectoverrideofObjectclass
I. publicinthashCode();II. publicStringtoString();III. publicbooleanequals(Objectobj);IV. publicClassgetClass();
A. I,II,III,IV.
B. I,II,III.
C. I,II.
D. III,IV.
E. All.
OptionBiscorrect.
TheObjectclasshasallthemethodsignaturespecifiedabovesotheoverrideispossibleonalloptionslessIVbecauseisdeclaredfinalinObjectclass,soBiscorrect.
Examobjective:JavaClassDesign-OverridehashCode,equals,andtoStringmethodsfromObjectclass
OracleReference:https://docs.oracle.com/javase/tutorial/java/IandI/objectclass.html
https://www.certification-questions.com/
Q9.Given
1. publicclassTest{2. publicstatic<T>intcount(T[]array,Telem){3. intcount=0;4. for(Te:array)5. if(e.compareTo(elem)>0)++count;6. 7. returncount;8. }9. publicstaticvoidmain(String[]args){10. Integer[]a={1,2,3,4,5};11. intn=Test.<Integer>count(a,3);12. System.out.println(n);13. }14. }
whatwillbetheresult?
A. 2
B. 3
C. Thecodewillnotcompilebecauseofline5.
D. Anexceptionisthrown.
E. NoneofAbove.
OptionCiscorrect.
Ciscorrectbecausethevariable"e"isageneric"T"typesothecompilehasnoknowledgeofmethod"compareTo",tomakeitcompileline2needtobechangedin:
publicstatic<TextendsComparable<T>>intcount(T[]array,Telem){
Examobjective:CollectionsandGenerics-Creatingacustomgenericclass
OracleReference:https://docs.oracle.com/javase/tutorial/java/generics/methods.html
https://www.certification-questions.com/
Q10.Given
1. publicclassProgram{2. publicstaticvoidmain(String[]args){3. 4. Threadth=newThread(newRunnable(){ 5. 6. static{7. System.out.println("initial");8. }9. 10. @Override11. publicvoidrun(){12. System.out.println("start");13. }14. });15. 16. th.start();17. }18. }
Whatwillbetheresult?
A. startinitial
B. initialstart
C. initial
D. Aruntimeexceptionisthrown.
E. Thecodewillnotcompilebecauseofline6.
OptionEiscorrect.
Becauseyoucannotdeclarestaticinitializersinananonymousclass,thecompilationfailatline6,soEiscorrectandA,B,C,Dincorrect.
Examobjective:InterfacesandLambdaExpressions-Anonymousinnerclasses
OracleReference:https://docs.oracle.com/javase/tutorial/java/javaOO/anonymousclasses.html
https://www.certification-questions.com/
Q11.Considerthefollowingclass.
1. finalclassA{2. privateStrings;3. publicA(Strings){4. this.s=s;5. }6. publicStringtoString(){returns;};7. publicvoidsetA(Stringa){this.s+=a;};8. }9. 10. publicfinalclassImmutable{11. privatefinalAa;12. publicImmutable(Aa){13. this.a=a;14. }15. publicStringtoString(){returna.toString();};16. publicstaticvoidmain(String[]args){17. 18. Aa=newA("Bye");19. Immutableim=newImmutable(a);20. System.out.print(im);21. 22. a.setA("bye");23. System.out.print(a);24. }25. }
Whatwillbetheresult?
A. Byebye
B. ByeBye
C. ByeByebye
D. Compilationfail
E. NoneofAbove
OptionBiscorrect.
Theobject"im"isnotreallyanimmutableobject.TheclassDon'tprovide"setter"methods,fieldisfinalandprivate,don'tallowsubclassestooverridemethods,unfortunatelyinconstructurObjectaismutableandpassbyreferencewithoutmakeaprotectioncopyoftheobject.
Examobjective:EncapsulationandSubclassing-Makingclassesimmutable.
OracleReference:https://docs.oracle.com/javase/tutorial/essential/concurrency/imstrat.html
https://www.certification-questions.com/
Q12.Given
1. //CodeHere2. @Override3. publicvoidrun(){4. for(inti=0;i<10;i++)5. System.out.print(i);6. }7. }8. 9. publicclassTest{10. publicstaticvoidmain(Stringargs[]){11. Taskt=newTask();12. Threadthread=newThread(t);13. thread.start();14. }15. }
Whichofthefollowinglineswillgivetheresult:
0123456789
A. classTaskextendsRunnable{
B. classTaskimplementsRunnable{
C. classTaskimplementsThread{
D. classTaskextendsThread{
E. NoneOfAbove
OptionBiscorrect.
WecancreateathreadbypassinganimplementationofRunnabletoaThreadconstructor,
sotheonlycorrectoptionisB
Examobjective:Concurrency-CreatingworkerthreadsusingRunnableandCallable.
OracleReference:https://docs.oracle.com/javase/tutorial/essential/concurrency/
https://www.certification-questions.com/
Q13.Given
1. publicclassProgram{2. 3. publicstaticvoidmain(String[]args){4. 5. Callable<String>c=newCallable<String>(){6. @Override7. publicStringcall()throwsException{8. Strings="";9. for(inti=0;i<10;i++){s+=i;}10. returns;11. }12. };13. 14. ExecutorServiceexecutor=Executors.newSingleThreadExecutor();15. Future<String>future=executor.submit(c);16. try{17. Stringresult=future.wait();18. System.out.println(result);19. }catch(ExecutionExceptione){20. e.printStackTrace();21. }22. }23. }
Whatwillbetheresult?
A. 0123456789
B. 12345678910
C. UnhandledexceptiontypeInterruptedExceptionalline17
D. Thecodewillnotcompilebecauseofline5.
E. Thecodewillnotcompilebecauseofline17.
OptionEiscorrect.
WearecreatingaCallableobjectwithananonymousclassatline5,syntaxiscorrectsooptionCisincorrect.Passingtheobject"c"toanexecutorandgetasreturntypeaFuturetowaitforthreadends.Butatline17methodwaitofClassFuturedoesn'texistsoEiscorrect.
Examobjective:Concurrency-CreatingworkerthreadsusingRunnableandCallable.
OracleReference:https://docs.oracle.com/javase/tutorial/essential/concurrency/
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Q14.WhichofthefollowingsarevalidExecutorsfactorymethods:
I. ExecutorServicees1=Executors.newSingleThreadExecutor(4);II. ExecutorServicees1=Executors.newFixedThreadPool(10);III. ExecutorServicees1=Executors.newScheduledThreadPool();IV. ExecutorServicees1=Executors.newScheduledThreadPool(10);V. ExecutorServicees1=Executors.newSingleThreadScheduledExecutor();
A. I,II,III
B. II,III,IV,V
C. I,IV,V
D. II,IV,IV
E. All
OptionDiscorrect.
Themethod"newSingleThreadExecutor"cannotacceptparametersIisincorrect,themethod"newScheduledThreadPool"withparametersdoesn'texistssoIIIisincorrect.
Examobjective:Concurrency-UsinganExecutorServicetoconcurrentlyexecutetasks.
OracleReference:https://docs.oracle.com/javase/tutorial/essential/concurrency/
https://www.certification-questions.com/
Q15.Given
1. classA{2. privateStrings;3. publicA(Stringin){this.s=in;}4. 5. publicbooleanequals(Objectin){6. if(getClass()!=in.getClass())returnfalse;7. Aa=(A)in;8. booleanret=(this.s.equals(a.s));9. returnret;10. }11. };12. 13. publicclassProgram{14. publicstaticvoidmain(String[]args){15. Aa1=newA("A");16. Aa2=newA("A");17. if(a1==a2)System.out.println("true");18. elseSystem.out.println("false");19. }20. }
Whatwillbetheresult?
A. true
B. false
C. Thecodewillnotcompilebecauseofline17.
D. UnhandledexceptiontypeClassCastExceptionalline7.
E. Noneofabove
OptionBiscorrect.
InclassAthemethodequalsisbeenoverrideinacorrectway,anywaytheoperator"=="willcontinuetocompareobjectreference,sooptionBiscorrect.
Examobjective:JavaClassDesign-OverridehashCode,equals,andtoStringmethodsfromObjectclass
OracleReference:https://docs.oracle.com/javase/tutorial/java/IandI/objectclass.html
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Q16.Giventheclassdefinition
1. classG<T>{2. privateTt;3. 4. publicvoidset(Tt){this.t=t;}5. publicTget(){returnt;}6. }
WhichofthefollowingarevalidGClassinstantiation.
I. G<String>gen=newG<String>();II. G<>gen=newG<>();III. Ggen=newG();IV. G<A<String>>gen=newG<A<String>>();V. G<int>gen=newG<int>();
F. I,II,III.
G. I,II,IV.
H. I,III.
I. I,III,IV.
J. All.
OptionDiscorrect.
Atypevariablecanbeanynon-primitivetypeandanothertypevariable,sooptionI,IVarecorrectandVincorrect,optionIIisincorrectbecausemissthetypevariable,optionIIIiscorrectbecauseistherawtypeofG<T>.
Examobjective:CollectionsandGenerics-Creatingacustomgenericclass
OracleReference:https://docs.oracle.com/javase/tutorial/java/generics/types.html
https://www.certification-questions.com/
Q17.Given
1. classPerson{2. privateStringname;3. privateintage;4. Person(Stringname,intage){5. this.name=name;6. this.age=age;7. }8. publicStringtoString(){returnname+""+age;}9. 10. publicstaticComparator<Person>COMPARATOR=newComparator<Person>(){11. publicintcompare(Persono1,Persono2){12. return(o1.age-o2.age);13. } 14. }; 15. }16. publicclassProgram{17. 18. publicstaticvoidmain(String[]args){19. List<Person>list=newArrayList<Person>();20. list.add(newPerson("John",50));21. list.add(newPerson("Frank",15));22. list.add(newPerson("Adam",20));23. 24. Collections.sort(list,Person.COMPARATOR);25. list.forEach(a->System.out.print(a.toString()+""));26. }27. }
whatwillbetheresult?
A. Adam20Frank15John50
B. John50Adam20Frank15
C. Frank15Adam20John50
D. Thecodewillnotcompilebecauseofline24.
E. UnhandledexceptiontypeClassCastExceptionalline24.
OptionCiscorrect.
WiththeuseofTheComparatorObjectdefinedinline10wesortobjectsinanorderotherthantheirnaturalordering,thatistheageinstanceattribute,thanoptionCiscorrectmeanwhileAandBincorrect.ThecodehasnocompileerrorandnoexceptionwillthrowsooptionDeEareincorrect.
Examobjective:CollectionsandGenerics-Orderingcollections
OracleReference:https://docs.oracle.com/javase/tutorial/collections/interfaces/order.html
https://www.certification-questions.com/
Q18.Giventhefollowingcode
1. interfaceA{2. publicvoidm();3. };4. publicclassProgram{5. publicstaticvoidmain(String[]args){6. inty=0;7. //CodeHere8. }9. }
Whatarevalidanonymousclassdeclaration:
I. newA(){voidm1(){};publicvoidm(){};};
II. newA(){staticintx;publicvoidm(){};
};III. newA(){
publicvoidm(){y++;};};
IV. newA(){staticfinalintx=0;publicvoidm(){};
};
F. I,II,III.
G. I,IV.
H. I,II.
I. II,IV.
J. All.
OptionBiscorrect.
Ananonymousclasscannotaccesslocalvariablesinitsenclosingscopethatarenotdeclaredasfinaloreffectivelyfinal,soIIIisincorrect.Ananonymousclasscanhavestaticmembersprovidedthattheyareconstantvariables,thenIIisincorrect.OptionIandIVarevaliddeclaration,soBiscorrect.
Examobjective:InterfacesandLambdaExpressions-Anonymousinnerclasses
OracleReference:https://docs.oracle.com/javase/tutorial/java/javaOO/anonymousclasses.html
https://www.certification-questions.com/
Q19.Given
1. classPerson{2. privateStringname;3. privateintage;4. Person(Stringname,intage){5. this.name=name;6. this.age=age;7. }8. 9. publicStringtoString(){returnname+""+age;}10. 11. publicstaticComparator<Person>COMPARATOR=newComparator<Person>(){12. publicintcompare(Persono1,Persono2){13. return(o1.age-o2.age);14. }; 15. }; 16. };17. publicclassProgram{18. 19. publicstaticvoidmain(String[]args){20. Set<Person>list=newTreeSet<Person>(Person.COMPARATOR);21. list.add(newPerson("John",50));22. list.add(newPerson("Frank",15));23. list.add(newPerson("Adam",15));24. list.forEach(a->System.out.print(a.toString()+""));25. }26. }
whatwillbetheresult?
A. Frank15John50
B. John50Adam20Frank15
C. Frank15Adam20John50
D. Thecodewillnotcompilebecauseofline20.
E. UnhandledexceptiontypeClassCastExceptionalline20.
OptionAiscorrect.
TreeSetisaSortSetsoweneedtopassaComparatorobjectintheconstructorormaketheobjectPersonComparable.TheSetcollectiondoesn'tallowduplicatekeysandmethod"compare"isusedforobjectequality,butwearecomparingonlyageattributeandthanOptionAiscorrectandBandCareincorrect.ThecodehasnocompileerrorandnoexceptionwillthrowsooptionDeEareincorrect.
Examobjective:CollectionsandGenerics-Orderingcollections
OracleReference:https://docs.oracle.com/javase/tutorial/collections/interfaces/order.html
https://www.certification-questions.com/
Q20.Given
1. publicclassProgram{2. 3. publicstaticvoidmain(String[]args){4. Stringurl="jdbc:derby:testdb;create=true";5. try{6. Connectionconn=DriverManager.getConnection(url); 7. 8. Stringquery="selectnamefromcontacts";9. Statementstmt=conn.createStatement();10. 11. ResultSetrs=stmt.execute(query);12. while(rs.next()){13. Stringname=rs.getString("Name");14. System.out.println(name);15. }16. }catch(SQLExceptione){17. System.out.println(e.getMessage());18. }19. }20. }
Whatwillbetheresult?
A. Thecodewillnotcompilebecauseofline11.
B. Theprogramwillrunsuccessful.
C. Thecodewillnotcompilebecauseofline9.
D. Anexceptionisthrown.
E. NoneofAbove.
OptionAiscorrect.
OptionAiscorrectasthecodefailstocompile,themethod"execute"doesn'treturnaResultSetbuttrueifthefirstobjectthatthequeryreturnsisaResultSetobject,tomakethecodecompiletherightmethodis"executeQuery".
Examobjective:DatabaseApplicationswithJDBC-Submittingqueriesandgetresultsfromthedatabase.
OracleReference:https://docs.oracle.com/javase/tutorial/jdbc/overview/
https://www.certification-questions.com/
Q21.Given
1. publicclassProgram{2. publicstatic<T>intcount(T[]array){3. intcount=0;4. for(Te:array)++count;5. returncount;6. }7. publicstaticvoidmain(String[]args){8. Integer[]a={1,2,3,4,5};9. //Codehere10. System.out.println(n);11. }12. }
whichofthefollowingarevalidmethod'sinvocation.
A. intn=<Integer>Program.count(a);
B. intn=Program.<Integer>count(a);
C. intn=Program.count<Integer>(a);
D. intn=Program.count(a);
E. All
OptionBandDarecorrect.
OptionAandCareincorrectsyntaxforgenericmethodinvocation,optionBisthecorrectsyntaxforgenericmethodinvocation,typeinferenceallowsyoutoinvokeagenericmethodasanordinarymethodsooptionDiscorrectaswell.
Examobjective:CollectionsandGenerics-Creatingacustomgenericclass
OracleReference:https://docs.oracle.com/javase/tutorial/java/generics/methods.html
https://www.certification-questions.com/
Q22.WhichofthefollowingStatementaretrue
I. Ananonymousclasshasaccesstothemembersofitsenclosingclass.
II. Ananonymousclasscannotaccesslocalvariablesinitsenclosingscopethatarenot
declaredasfinaloreffectivelyfinal.
III.Youcannotdeclarestaticinitializersormemberinterfaces.
IV. Ananonymousclasscanhavestaticmembersprovidedthattheyareconstantvariables.
A. I,II,III.
B. I,II.
C. II,III,IV.
D. III,IV.
E. All.
OptionEiscorrect.
Examobjective:InterfacesandLambdaExpressions-Anonymousinnerclasses
OracleReference:https://docs.oracle.com/javase/tutorial/java/javaOO/anonymousclasses.html
https://www.certification-questions.com/
Q23.Given
1. classA{2. privateStrings;3. publicA(Strings){this.s=s;};4. publicStringtoString(){returns;}5. }6. publicclassProgram{7. 8. publicstaticvoidmain(String[]args){9. 10. List<A>list=newArrayList<A>();11. list.add(newA("flower"));12. list.add(newA("cat"));13. list.add(newA("house"));14. list.add(newA("dog"));15. Collections.sort(list);16. list.forEach(a->System.out.print(a.toString()+""));17. }18. }
Whatwillbetheresult?
A. houseflowerdogcat
B. catdogflowerhouse
C. flowercathousedog
D. Thecodewillnotcompilebecauseofline15.
E. UnhandledexceptiontypeClassCastExceptionalline15.
OptionDiscorrect.
Object"list"isatypeAArrayList,theCollections"sort"methodhassignatureasfollowing:
Collectios<TextendsComparable<?superT>>voidsort(List<T>list)
SothecodewillnotcompilebecauseclassAdoesn'timplementComparableinterface,andthanD
iscorrectandA,B,CandEareincorrect.
Examobjective:CollectionsandGenerics-Orderingcollections
OracleReference:https://docs.oracle.com/javase/tutorial/collections/interfaces/order.html
https://www.certification-questions.com/
Q24.WhichofthosearevalidStandardStreams
I. System.in
II. System.error
III.System.out
IV. System.input
V. System.output
A. I.
B. II,IV,V.
C. I,II,III.
D. I,III.
E. Anyofabove.
OptionDiscorrect.
System.error,System.inputandSystem.outputarenotvalidsyntax,sothecorrectanswerisD.
Examobjective:I/OFundamentals-Readandwritedatafromtheconsole
OracleReference:https://docs.oracle.com/javase/tutorial/essential/io/cl.html
https://www.certification-questions.com/
Q25.Whichis/aretrue?
I. InFileInputStreamandFileOutputStreameachreadorwriterequestishandleddirectly
bytheunderlyingOS.
II. Programsusebytestreamstoperforminputandoutputof8-bitbytes.
III.CharacterstreamI/Oautomaticallytranslatesthisinternalformattoandfromthe
localcharacterset.
IV. Therearetwogeneral-purposebyte-to-character"bridge"streams:InputStreamReader
andOutputStreamWriter.
A. I,II,III,IV.
B. II,III.
C. II,III,IV.
D. III,IV.
E. All.
OptionEiscorrect.
Examobjective:I/OFundamentals-Usingstreamstoreadandwritefiles
OracleReference:https://docs.oracle.com/javase/tutorial/essential/io