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104年 - SCJP 51-100#99391

科目：OJCP(SCJP) | 年份：104年 | 選擇題數：37 | 申論題數：13

試卷資訊

所屬科目：OJCP(SCJP)

選擇題 (37)

51. Given:
  60cc01406fe9f.jpg60cc016c2122d.jpgWhich statement is true about the classes and interfaces? (A) Compilation will succeed for all classes and interfaces. (B) Compilation of class C will fail because of an error in line 2. (C) Compilation of class C will fail because of an error in line 6. (D) Compilation of class AImpl will fail because of an error in line 2.

54. Given: 
1. package test； 
2. 
3. class Target{
 4. public String name = "hello"；
 5. }
 What can directly access and change the value of the variable name? (A) any class (B) only the Target class (C) any class in the test package (D) any class that extends Target
55. Given: 
11. abstract class Vehicle{public int speed(){return 0；}} 
12. class Car extends Vehicle{public int speed(){return 60；}} 
13. class RaceCar extends Car{public int speed(){return 150；}}
 ...
 21. RaceCar racer = new RaceCar()； 
22. Car car = new RaceCar()； 
23. Vehicle vehicle = new RaceCar()； 
24. System.out.println(racer.speed() + ", " + car.speed()
 25. + ", " + vehicle.speed())； 
What is the result? (A) 0, 0, 0 (B) 150, 60, 0 (C) Compilation fails. (D) 150, 150, 150 (E) An exception is thrown at runtime.
56. Given: 
5. class Building{}
 6. public class Barn extends Building{ 
7. public static void main(String[] args){ 
 8. Building build1 = new Building()；
 9. Barn barn1 = new Barn()； 
10. Barn barn2 = (Barn)build1； 
11. Object obj1 = (Object)build1； 
12. String str1 = (String)build1； 
13. Building build2 = (Building)barn1； 
14. } 
15. } 
Which is true? (A) if line 10 is removed, the compilation succeeds. (B) if line 11 is removed, the compilation succeeds. (C) if line 12 is removed, the compilation succeeds. (D) if line 13 is removed, the compilation succeeds. (E) More than one line must be removed for compilation to succeed.
57. Given:
 21. class Money{ 
22. private String country = "Canada"； 
23. public String getC(){return country；} 
24. }
 25. class Yen extends Money{ 
26. public String getC(){return super.country；} 
27. }
 28. public class Euro extends Money{ 
29. public String getC(){return super.getC()；} 
30. public static void main(String[] args){ 
31. System.out.print(new Yen().getC() + " " + new Euro().getC())； 
32. } 
33. }
 What is the result? (A) Canada (B) null Canada (C) Canada null (D) Canada Canada (E) Compilation fails due to an error on line 26.
58. Given: 
 10. interface Foo{} 
11. class Alpha implements Foo{} 
12. class Beta extends Alpha{}
 13. class Delta extends Beta{ 
14. public static void main(String[] args){
 15. Beta x = new Beta()； 
16. //insert code here 
17. }
 18. } 
Which code, inserted at line 16, will cause a java.lang.ClassCastException? (A) Alpha a = x； (B) Foo f = (Delta)x； (C) Foo f = (Alpha)x； (D) Beta b = (Beta)(Alpha)x；

59. Given the following directory structure:
  60cc035dc5cf7.jpg (A) If the compile is successful, Utils.class is added to the source directory. (B) The compiler returns an invalid flag error. (C) If the compile is successful, Utils.class is added to the classes directory. (D) If the compile is successful, Utils.class is added to the bigProject directory.

複選題
60. Given: 
1. package com.company.application；
 2.
 3. public class MainClass{
 4. public static void main(String[] args){} 
5. }
 And MainClass exists in the /apps/com/company/application directory. Assume the CLASSPATH environment variable is set to "." (current directory). 
Which two java commands entered at the command line will run MainClass? (Choose two.) (A) java MainClass if run from the /apps directory (B) java com.company.application.MainClass if run from the /apps directory (C) java -classpath /apps com.company.application.MainClass if run from any directory (D) java-classpath . MainClass if run from the /apps/com/company/application directory (E) java -classpath /apps/com/company/application:. MainClass if run from the /apps directory
61. Given two files, GrizzlyBear.java and Salmon.java: 
1. package animals.mammals； 
2. 
3. public class GrizzlyBear extends Bear{ 
4. void hunt() { 
5. Salmon s = findSalmon()；
 6. s.consume()；
 7. }
 8. 
} 1. package animals.fish； 
2.
 3. public class Salmon extends Fish {
 4. public void consume() { /* do stuff */ }
 5. }
 If both classes are in the correct directories for their packages, and the Mammal class correctly defines the findSalmon() method, which change allows this code to compile? (A) add import animals. mammals.*； at line 2 in Salmon.java (B) add import animals.fish.*； at line 2 in GrizzlyBearjava (C) add import animals.fish.Salmon.*； at line 2 in GrizzlyBear.java (D) add import animals. mammals.GrizzlyBear*； at line 2 in Salmon.java
62. Given: 
31. class Foo{ 
32. public int a = 3； 
33. public void addFive(){ a += 5； System.out.print("f ")； } 
34. } 
35. class Bar extends Foo{ 
36. public int a = 8； 
37. public void addFive(){this.a += 5； System.out.print("b ")；} 
38. }
Invoked with: 
Foo f = new Bar()； 
f.addFive()；
 System.out.println(f. a)； 
What is the result? (A) b 3 (B) b 8 (C) b 13 (D) f 3 (E) f 8
複選題
67. Given: 
10. abstract public class Employee { 
11. protected abstract double getSalesAmount()； 
12. public double getCommision() { 
13. return getSalesAmount() * 0.15；
 14. } 
15. }
 16. class Sales extends Employee { 
17. //insert method here 
18. }
 Which two methods, inserted independently at line 17, correctly complete the Sales class? (Choose two.) (A) double getSalesAmount() { return 1230.45； } (B) public double getSalesAmount() { return 1230.45； } (C) private double getSalesAmount() { return 1230.45； } (D) protected double getSalesAmount() { return 1230.45； }
68. Given the following six method names:
 addListener 
addMouseListener
 setMouseListener
 deleteMouseListener
 removeMouseListener
 registerMouseListener 
How many of these method names follow JavaBean Listener naming rules? (A) 1 (B) 2 (C) 3 (D) 4 (E) 5
複選題
69. Given 
11. public interface Status { 
12. /* insert code here */ int MY_VALUE = 10； 
13. }
 Which three are valid on line 12? (Choose three.) (A) final (B) static (C) native (D) public (E) private

70.60cc0729119d9.jpgGiven the fully-qualified class names:
com.foo.bar.Dog
com.foo.bar.blatz.Book
com.bar.Car
com.bar.blatz.Sun
Which graph represents the correct directory structure for a JAR file from which those classes can be used by the compiler and JVM? (A) Jar A (B) Jar B (C) Jar C (D) Jar D (E) Jar E
72. Given: 
1. package geometry； 
2. public class Hypotenuse { 
3. public InnerTriangle it = new InnerTriangle()； 
4. class InnerTriangle { 
5. public int base； 
6. public int height； 
7. } 
8. }
 Which statement is true about the class of an object that can reference the variable base? (A) It can be any class. (B) No class has access to base. (C) The class must belong to the geometry package. (D) The class must be a subclass of the class Hypotenuse.
73. Given: 
10. interface Data { public void load()； } 
11. abstract class Info { public abstract void load()； }
 Which class correctly uses the Data interface and Info class? (A) public class Employee extends Info implements Data {public void load(){ /* do something */ } } (B) public class Employee implements Info extends Data { public void load(){ /* do something */ } } (C) public class Employee extends Info implements Data public void load(){ /* do something */ } public void Info.load(){ /* do something */ } } (D) public class Employee implements Info extends Data { public void Data.load(){ /* do something */ } public void load(){ /* do something */ } } (E) public class Employee implements Info extends Data { public void load(){ /* do something */ } public void Info.load(){ /* do something */ }
複選題
74. Which two classes correctly implement both the java.lang.Runnable and the java.lang.Cloneable interfaces?
 (Choose two.) (A) public class Session implements Runnable, cloneable { public void run()； public Object clone()； } (B) public class Session extends Runnable, Cloneable { public void run(){/* do something */} public Object clone(){/* make a copy */} } (C) public class Session implements Runnable, Cloneable { public void run(){/* do something */} public Object clone() {/* make a copy */} } (D) public abstract class Session implements Runnable, Cloneable { public void run(){/* do something */} public Object clone(){/* make a copy */} } (E) public class Session implements Runnable, implements Cloneable { public void run(){/* do something */} public Object clone() {/* make a copy */} }
75. Given: 
11. public interface A{ public void m1()； }
 13. class B implements A{ } 
14. class C implements A{ public void m1(){}} 
15. class D implements A{ public void m1(int x){}} 
16. abstract class E implements A {} 
17. abstract class F implements A { public void m1(){} } 
18. abstract class G implements A { public void m1(int x){} }
 What is the result? (A) Compilation succeeds. (B) Exactly one class does NOT compile. (C) Exactly two classes do NOT compile. (D) Exactly four classes do NOT compile. (E) Exactly three classes do NOT compile.
76. Given:
 1. class TestA{ 
2. public void start(){System.out.println("TestA")；} 
3. } 
4. public class TestB extends TestA{ 
5. public void start(){System.out.println("TestB")；}
 6. public static void main(String[] args){ 
7. ((TestA)new TestB()).start()； 
8. } 
9. }
 What is the result? (A) TestA (B) TestB (C) Compilation fails. (D) An exception is thrown at runtime.
77. Given: 
11. public static void main(String[] args) { 
 12. Object obj = new int{1, 2, 3}； 
13. int[] someArray = (int[])obj； 
14. for (int i: someArray) System.out.print(i + " ")；
 15. }
 What is the result? (A) 1 2 3 (B) Compilation fails because of an error in line 12. (C) Compilation fails because of an error in line 13. (D) Compilation fails because of an error in line 14. (E) A ClassCastException is thrown at runtime.
79. Given classes defined in two different files: 
1. package packageA； 2
. public class Message{ 
3. String getText(){return "text"；} 
4. }
 And: 
1. package packageB； 
2. public class XMLMessage extends packageA .Message{
 3. String getText(){return "＜msg＞text＜/msg＞"；} 
4. public static void main(String[] args) { 
5. System.out.println(new XMLMessage().getText())； 
6. }
 7. }
 What is the result of executing XMLMessage.main? (A) text (B) Compilation fails. (C) ＜msg＞text＜/msg＞ (D) An exception is thrown at runtime.
80. Given: 
3. interface Fish{}
 4. class Perch implements Fish{} 
5. class Walleye extends Perch{} 
6. class Bluegill{} 
7. public class Fisherman {
 8. public static void main(String[] args) { 
9. Fish f = new Walleye()； 
10. Walleye w = new Walleye() 
11. Bluegill b = new Bluegill()； 
12. if(f instanceof Perch) System.out.print("f-p ")； 
13. if(w instanceof Fish) System.out.print("w-f ")； 
14. if(b instanceof Fish) System.out.print("b-f ")； 
15. } 
16. } 
What is the result? (A) w-f (B) f-p w-f (C) w-f b-f (D) f-p w-f b-f (E) Compilation fails.
81. Given:
 1. interface DoStuff2{ 
2. float getRange(int low, int high)；} 
 3.
 4. interface DoMore {
 5. float getAvg(int a, int b, int c)；} 
6. 
7. abstract class DoAbstract implements DoStuff2, DoMore{} 
8.
 9. class DoStuff implements DoStuff2{ 
10. public float getRange(int x, int y){return 3.14f；}} 
11. 
12. interface DoAll extends DoMore{ 
13. float getAvg(int a, int b, int c, int d)；} 
What is the result? (A) The file will compile without error. (B) Compilation fails. Only line 7 contains an error. (C) Compilation fails. Only line 12 contains an error. (D) Compilation fails. Only line 13 contains an error. (E) Compilation fails. Only lines 7 and 12 contain errors. F. Compilation fails. Only lines 7 and 13 contain errors. G. Compilation fails. Lines 7, 12, and 13 contain errors.
82. Given: 
11. public interface A111{ 
12. String s = "yo"； 
13. public void method1()；
14. } 
17. interface B{} 
20. interface C extends A111, B{ 
21. public void method1()； 
22. public void method1(int x)； 
23. }
 What is the result? (A) Compilation succeeds. (B) Compilation fails due to multiple errors. (C) Compilation fails due to an error only on line 20. (D) Compilation fails due to an error only on line 21. (E) Compilation fails due to an error only on line 22.
84. Given: 
11. class Alpha{
 12. public void foo(){System.out.print("Afoo ")；}
 13. } 
14. public class Beta extends Alpha{ 
15. public void foo(){System.out.print("Bfoo ")；} 
16. public static void main(String[] args){
 17. Alpha a = new Beta()； 
18. Beta b = (Beta)a； 
19. a.foo()；
20. b.foo()； 
21. }
 22. } 
What is the result? (A) Afoo Afoo (B) Afoo Bfoo (C) Bfoo Afoo (D) Bfoo Bfoo (E) Compilation fails.
85. Given:
 11. class Animal{public String noise(){return "peep"；}} 
12. class Dog extends Animal{ 
13. public String noise(){return "bark"；}
 14 } 
15. class Cat extends Animal{ 
16. public String noise(){return "meow"；} 
17. } ... 
30. Animal animal = new Dog()；
 31. Cat cat = (Cat)animal；
32. System.out.println(cat.noise())； 
What is the result? (A) peep (B) bark (C) meow (D) Compilation fails. (E) An exception is thrown at runtime.
87. A team of programmers is involved in reviewing a proposed design for a new utility class, After some discussion, they realize that the current design allows other classes to access methods in the utility class that should be accessible only to methods within the utility class itself. What design issue has the team discovered? (A) Tight coupling (B) Low cohesion (C) High cohesion (D) Loose coupling (E) Weak encapsulation
複選題
89. Given: 
1. public class Car{
 2. private int wheelCount； 
3. private String vin； 
4. public Car(String vin){ 
5. this.vin = vin； 
6. this.wheelCount = 4； 
7. }
 8. public String drive(){
 9. return "zoom-zoom"； 
10. }
 11. public String getInfo(){ 
12. return "VIN: " + vin + "wheels: " + wheelCount； 
13. } 
14. } 
And:
 1. public class MeGo extends Car{
 2. public MeGo(String vin){ 
3. this.wheelCount = 3； 
4. }
 5. }
 What two must the programmer do to correct the compilation errors? (Choose two.) (A) insert a call to this() in the Car constructor (B) insert a call to this() in the MeGo constructor (C) insert a call to super() in the MeGo constructor (D) insert a call to super(vin) in the MeGo constructor (E) change the wheelCount variable in Car to protected
90. Given:
 11. interface DeclareStuff{ 
12. public static final int EASY = 3； 
13. void doStuff(int t)；}
 14. public class TestDeclare implements DeclareStuff{
 15. public static void main(String[] args){ 
16. int x = 5；
 17. new TestDeclare().doStuff(++x)； 
18. }
 19. void doStuff(int s){ 
20. s += EASY + ++s； 
21. System.out.println("s " + s)； 
22. }
 23. }
 What is the result? (A) s 14 (B) s 16 (C) s 10 (D) Compilation fails. (E) An exception is thrown at runtime.
92. Given a correctly compiled class whose source code is:
 1. package com.sun.sjcp；
 2. public class Commander { 
3. public static void main(String[] args) { 
4. // more code here 
5. } 
6. } Assume that the class file is located in /foo/com/sun/sjcp/, the current directory is /foo/, and that the classpath contains "." 
(current directory). 
Which command line correctly runs Commander? (A) java Commander (B) java com.sun.sjcp.Commander (C) java com/sun/sjcp/Commander (D) java -cp com.sun.sjcp Commander (E) java -cp com/sun/sjcp Commander
93. Given:
 10. class Nav{ 
11. public enum Direction { NORTH, SOUTH, EAST, WEST } 
12. }
 13. public class Sprite{ 
14. //insert code here 
15. } 
Which code, inserted at line 14, allows the Sprite class to compile? (A) Direction d = NORTH； (B) Nav.Direction d = NORTH； (C) Direction d = Direction.NORTH； (D) Nav.Direction d = Nav.Direction.NORTH；
94. Given:
 11. public class Rainbow { 
12. public enum MyColor { 
13. RED(0xff0000), GREEN(0x00ff00), BLUE(0x0000ff)； 
14. private final int rgb； 
15. MyColor(int rgb){this.rgb = rgb；} 
16. public int getRGB(){return rgb；}
 17. } 
18. public static void main(String[] args){ 
19. //insert code here 
20. } 
21. } 
Which code fragment inserted at line 19, allows the Rainbow class to compile? (A) MyColor skyColor = BLUE； (B) MyColor treeColor = MyColor.GREEN； (C) if(RED.getRGB() ＜ BLUE.getRGB()){} (D) Compilation fails due to other error(s) in the code. (E) MyColor purple = new MyColor(0xff00ff)；
95. Given: 
1. interface TestA{String toString()；}
 2. public class Test{ 
3. public static void main(String[] args){
 4. System.out.println(new TestA(){ 
5. public String toString(){return "test"；} 
6. })； 
7. } 
8. } 
What is the result? (A) test (B) null (C) An exception is thrown at runtime. (D) Compilation fails because of an error in line 1. (E) Compilation fails because of an error in line 4.
97. Which statement is true? (A) A class's finalize() method CANNOT be invoked explicitly. (B) super.finalize() is called implicitly by any overriding finalize() method. (C) The finalize() method for a given object is called no more than once by the garbage collector. (D) The order in which finalize() is called on two objects is based on the order in which the two objects became finalizable.
98. Given: 
15. public class Yippee{ 
16. public static void main(String[] args){
 17. for(int x = 1； x ＜ args.length； x++){ 
18. System.out.print(args[x] + " ")； 
19. } 
20. } 
21. } 
and two separate command line invocations:
 java Yippee
 java Yippee 1 2 3 4
 What is the result? (A) No output is produced. 1 2 3 (B) No output is produced. 2 3 4 (C) No output is produced. 1 2 3 4 (D) An exception is thrown at runtime. 1 2 3 (E) An exception is thrown at runtime. 2 3 4 F. An exception is thrown at runtime. 1 2 3 4
99. Given: 
3. interface Animal{void makeNoise()；} 
4. class Horse implements Animal{ 
5. Long weight = 1200L；
 6. public void makeNoise(){System.out.println("whinny")；} 
7. } 
8. public class lcelandic extends Horse{
 9. public void makeNoise(){System.out.println("vinny")；} 
10. public static void main(String[] args) { 
11. Icelandic i1 = new lcelandic()； 
12. Icelandic i2 = new lcelandic()； 
13. Icelandic i3 = new lcelandic()； 
14. i3 = i1； i1 = i2； i2 = null； i3 = i1； 
15. } 
16. }
 When line 14 is reached, how many objects are eligible for the garbage collector? (A) 0 (B) 1 (C) 2 (D) 3 (E) 4
100. Given:
 10. public class SuperCalc{ 
11. protected static int multiply(int a, int b){return a * b；}
 12. }
 and: 
20. public class SubCalc extends SuperCalc{
 21. public static int multiply(int a, int b){ 
22. int c = super.multiply(a, b)；
 23. return c；
 24. } 
25. } 
and: 
30. SubCalc sc = new SubCalc()；
 31. System.out.println(sc.multiply(3, 4))； 
32. System.out.println(SubCalc.multiply(2, 2))；
 What is the result? (A) 12 4 (B) The code runs with no output. (C) An exception is thrown at runtime. (D) Compilation fails because of an error in line 21. (E) Compilation fails because of an error in line 22.

申論題 (13)

52. Place the code fragments in position to complete the Displayable interface. 60cc01bb6ec42.jpg60cc01d82615c.jpg
53. Insert six modifiers into the code such that it meets all of these requirements:
 1. It must be possible to create instances of Alpha and Beta from outside the packages in which they are defined. 
2. When an object of type Alpha (or any potential subclass of Alpha) has been created, the instance variable alpha may never be changed. 
3. The value of the instance variable alpha must always be "A" for objects of type Alpha.60cc021905ff3.jpg
63. Given: 
11. class ClassA{} 
12. class ClassB extends ClassA{}
 13. class ClassC extends ClassA{} 
and:
 21. ClassA p0 = new ClassA()； 
22. ClassB p1 = new ClassB()； 
23. ClassC p2 = new ClassC()； 
24. ClassA p3 = new ClassB()； 
25. ClassA p4 = new ClassC()；
 Which three are valid? (Choose three.) (A) p0 = p1； (B) p1 = p2, (C) p2 = p4； (D) p2 = (ClassC)p1； (E) p1 = (ClassB)p3； (F) p2 = (ClassC)p4；
64. Given: 
class A { 
 String name = "A"； 
 String getName() { 
 return name； 
 }
 String greeting(){
 return "class A"； 
 }
 } class B extends A {
 String name = "B"； 
 String greeting() { return "class B"；
 } 
}
 public class Client {
 public static void main( String[] args ) { 
 A a = new A()；
 A b = new B()；
 System.out.println(a.greeting() + "has name" + a.getName())；
 System.out.println(b.greeting() + "has name" + b.getName())； 
 }
 } 60cc05af76794.jpg
65. Replace two of the Modifiers that appear in the Single class to make the code compile.
 Note: Three modifiers will not be used and four modifiers in the code will remain unchanged. Code public class Single { private static Single instance； public static Single getInstance() { if (instance =60cc06108a6ec.jpg
66. Given: 
5. class Thingy{ Meter m = new Meter()； }
 6. class Component {void go() { System.out.print("c")；}} 
7. class Meter extends Component {void go() { System.out.print("m")； }} 
8.
 9. class DeluxeThingy extends Thingy { 
10. public static void main(String[] args) { 
11. DeluxeThingy dt = new DeluxeThingy()； 
12. dt.m.go()； 
13. Thingy t = new DeluxeThingy()； 
14. t.m.go()； 
15. } 
16. } Which two are true? (Choose two.) (A) The output is mm. (B) The output is mc. (C) Component is-a Meter. (D) Component has-a Meter. (E) DeluxeThingy is-a Component. (F) DeluxeThingy has-a Component.
71. Given:
 1. interface A{public void aMethod()；} JarB JarD JarE JarA JarC 
 2. interface B { public void bMethod()； } 
3. interface C extends A, B { public void cMethod()； } 
4. class D implements B { 
5. public void bMethod(){}
 6. }
 7. class E extends D implements C {
 8. public void aMethod(){} 
9. public void bMethod(){} 
10. public void cMethod(){}
 11. } 
What is the result? (A) Compilation fails because of an error in line 3. (B) Compilation fails because of an error in line 7. (C) Compilation fails because of an error in line 9. (D) If you define D e = new E(), then e.bMethod() invokes the version of bMethod() defined in Line 5. (E) If you define D e = (D)(new E()), then e.bMethod() invokes the version of bMethod() defined in Line 5. (F) If you define D e = (D)(new E()), then e.bMethod() invokes the version of bMethod() defined in Line 9.
78. A developer is creating a class Book, that needs to access class Paper. The Paper class is deployed in a JAR named myLib.jar. Which three, taken independently, will allow the developer to use the Paper class while compiling the Book class? (Choose Three.)
 (A) The JAR file is located at $JAVA_HOME/jre/classes/myLib.jar. (B) The JAR file is located at $JAVA_HOME/jre/lib/ext/myLib.jar. (C) The JAR file is located at /foo/myLib.jar and a classpath environment variable is set that includes /foo/myLib.jar/Paper.class. (D) The JAR file is located at /foo/myLib.jar and a classpath environment variable is set that includes /foo/myLib.jar. (E) The JAR file is located at /foo/myLib.jar and the Book class is compiled using javac -cp /foo/myLib.jar/Paper Book.java (F) The JAR file is located at /foo/myLib.jar and the Book class is compiled using javac -d /foo/myLib.jar Book.java (G) The JAR file is located at foo/myLib.jar and the Book class is compiled using javac -classpath /foo/myLib.jar Book.java
86. Given:
 10. abstract class A{ 
11. abstract void a1()； 
12. void a2(){} 
13. } 
14. class B extends A{ 
15. void a1(){} 16. void a2(){} 
 17. } 
18. class C extends B{void c1(){}} 
and: 
 A x = new B()； C y = new C()； A z = new C()；
 What are four valid examples of polymorphic method calls? (Choose four.) (A) x.a2()； (B) z.a2()； (C) z.c1()； (D) z.a1()； (E) y.c1()； (F) x.a1()；
88. Which Three statements are true?
 (Choose Three.)
 (A) A final method in class X can be abstract if and only if X is abstract. (B) A protected method in class X can be overridden by any subclass of X. (C) A private static method can be called only within other static methods in class X. (D) A non-static public final method in class X can be overridden in any subclass of X. (E) A public static method in class X can be called by a subclass of X without explicitly referencing the class X. (F) A method with the same signature as a private final method in class X can be implemented in a subclass of X. (G) A protected method in class X can be overridden by a subclass of X only if the subclass is in the same package as X.
96. Given a class Repetition: 
1. package utils； 
2. 
3. public class Repetition {
 4. public static String twice(String s){return s + s；} 
5. } 
and given another class Demo: 
1. // insert code here 
2.
 3. public class Demo { 
4. public static void main(String[] args){
 5. System.out.println(twice("pizza"))； 
6. } 
7. }
 Which code should be inserted at line 1 of Demo.java to compile and run Demo to print "pizzapizza"? (A) import utils.*； (B) static import utils.*； (C) import utils.Repetition.*； (D) static import utils.Repetition.*； (E) import utils.Repetition.twice()； (F) import static utils.Repetition.twice； (G)static import utils.Repetition.twice；
83.
 Given: 
10. interface Foo{ 
11. int bar();
 12. } 
13. 
14. public class Beta { 
15. 
16. class A implements Foo{ 
17. public int bar(){return 1;} 
18. } 
19.
 20. public int fubar(Foo foo){return foo.bar();}
 21.
 22. public void testFoo(){ 
23.
 24. class A implements Foo{ 
25. public int bar() {return 2;} 
26. } 
27.
 28. System.out.println(fubar(new A()));
 29. }
 30
. 31. public static void main(String[] argv){ 
32. new Beta().testFoo(); 
33. }
 34. } 
Which three statements are true? (Choose three.) (A)Compilation fails. (B) The code compiles and the output is 2. (C)If lines 16, 17 and 18 were removed, compilation would fail. (D) If lines 24, 25 and 26 were removed, compilation would fail. (E)If lines 16, 17 and 18 were removed, the code would compile and the output would be 2. (F)If lines 24, 25 and 26 were removed, the code would compile and the output would be 1.
91. A class games.cards.Poker is correctly defined in the jar file Poker.jar. A user wants to execute the main method of Poker on a UNIX system using the command: java games.cards.Poker What allows the user to do this? 
H. put Poker.jar in directory /stuff/java, and set the CLASSPATH to include /stuff/java
 I. put Poker.jar in directory /stuff/java, and set the CLASSPATH to include /stuff/java/*.jar
 J. Put Poker.jar in directory /stuff/java, and set the CLASSPATH to include /stuff/java/Poker.jar 
K. put Poker.jar in directory /stuff/java/games/cards, and set the CLASSPATH to include /stuff/java
 L. put Poker.jar in directory /stuff/java/games/cards, and set the CLASSPATH to include /stuff/java/*.jar
 M. put Poker.jar in directory /stuff/java/games/cards, and set the CLASSPATH to include /stuff/java/Poker.jar