1. interface Animal { 2. void eat(); 3. } 4. 5. // insert code here 6. 7. public class HouseCat implements Feline { 8. public void eat() { } 9. } 和以下三个接口声明: interface Feline extends Animal { } interface Feline extends Animal { void eat(); } interface Feline extends Animal { void eat() { } } 分别插入到第 5 行,有多少行可以编译?()
第1题:
Which three demonstrate an “is a” relationship?()
第2题:
1. public class Exception Test { 2. class TestException extends Exception {} 3. public void runTest() throws TestException {} 4. public void test() /* Point X */ { 5. runTest(); 6. } 7. } At Point X on line 4, which code is necessary to make the code compile?()
第3题:
interface Animal { void soundOff(); } class Elephant implements Animal { public void soundOff() { System.out.println(“Trumpet”); } } class Lion implements Animal { public void soundOff() { System.out.println(“Roar”); } } class Alpha1 { static Animal get( String choice ) { if ( choice.equalsIgnoreCase( “meat eater” )) { return new Lion(); } else { return new Elephant(); } } } Which compiles?()
第4题:
现有: interface Data {public void load();} abstract class Info {public abstract void load();} 下列类定义中正确使用Data和Info的是哪项?()
第5题:
interface A { public int getValue() } class B implements A { public int getValue() { return 1; } } class C extends B { // insert code here } Which three code fragments, inserted individually at line 15, make use of polymorphism?()
第6题:
1. class Animal { Animal getOne() { return new Animal(); } } 2. class Dog extends Animal { 3. // insert code here 4. } 5. 6. class AnimalTest { 7. public static void main(String [] args) { 8. Animal [] animal = { new Animal(), new Dog() } ; 9. for( Animal a : animal) { 10. Animal x = a.getOne(); 11. } 12. } 13. } 和代码: 3a. Dog getOne() { return new Dog(); } 3b. Animal getOne() { return new Dog(); } 第 3 行中插入的哪项将编译且运行无异常?()
第7题:
现有: 1. interface Animal { 2. void eat(); 3. } 4. 5. // insert code here 6. 7. public class HouseCat implements Feline { 8. public void eat() { } 9. } 和以下三个接口声明: interface Feline extends Animal { } interface Feline extends Animal { void eat(); } interface Feline extends Animal { void eat() { } } 分别插入到第 5 行,有多少行可以编译?()
第8题:
1. interface A { public void aMethod(); } 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?()
第9题:
No code is necessary.
throws Exception
catch ( Exception e )
throws RuntimeException
catch ( TestException e)
第10题:
public interface Person {} Public class Employee extends Person {}
public interface Shape {} public interface Rectangle extends Shape {}
public interface Color {} public class Shape { private Color color; }
public class Species {} public class Animal { private Species species; }
interface Component {} Class Container implements Component {private Component [] children;
第11题:
public class X { } public class Y extends X { }
public interface Shape { } public interface Rectangle extends Shape{ }
public interface Color { } public class Shape { private Color color; }
public interface Species { } public class Animal { private Species species; }
public class Person { } public class Employee { public Employee(Person person) { }
interface Component { } class Container implements Component { private Component[] children; }
第12题:
public class Employee extends Info implements Data { public void load() { /*do something*/ } }
public class Employee implements Info extends Data { public void load() { /*do something*/ } }
public class Employee extends Info implements Data { public void load() { /*do something */ } public void Info.load() { /*do something*/ } }
public class Employee implements Info extends Data { public void Data.load() { /*dsomething */ } public void load() { /*do something */ } }
public class Employee implements Info extends Data { public void load() { /*do something */ } public void Info.load(){ /*do something*/ } }
public class Employee extends Info implements Data{ public void Data.load() { /*do something*/ } public void Info.load() { /*do something*/ } }
第13题:
interface Data { public void load(); } abstract class Info { public abstract void load(); } Which class correctly uses the Data interface and Info class?()
第14题:
现自: 1. interface Color { } 2. interface Weight { } 3. //insert code here 和以下足六个声明: class Boat extends Color, extends Weight { } class Boat extends Color and Weight { } class Boat extends Color, Weight { } class Boat implements Color, implements Weight { } class Boat implements Color and Weight { } class Boat implements Color, Weight { } 分别插入到第3行,有多少行可以编译? ()
第15题:
现有: interface Animal { void eat () ; } //insert code here public class HouseCat extends Feline { public void eat() { } } 和五个申明 abstract class Feline implements Animal { } abstract class Feline implements Animal { void eat () ; } abstract class Feline implements Animal { public void eat();} abstract class Feline implements Animal { public void eat() {} } abstract class Feline implements Animal { abstract public void eat();} 结果为:()
第16题:
Which the two demonstrate an “is a” relationship?()
第17题:
Which two demonstrate an “is a” relationship?()
第18题:
现有: 1. interface Animal { 2. void eat(); 3. } 4. 5. // insert code here 6. 7. public class HouseCat extends Feline { 8. public void eat() { } 9. } 和五个声明: abstract class Feline implements Animal { } abstract class Feline implements Animal { void eat(); } abstract class Feline implements Animal { public void eat(); } abstract class Feline implements Animal { public void eat() { } } abstract class Feline implements Animal { abstract public void eat(); } 分别插入到第5行,有几个可以通过编译?()
第19题:
public abstract class Shape { private int x; private int y; public abstract void draw(); public void setAnchor(int x, int y) { this.x = x; this.y = y; } } Which two classes use the Shape class correctly?()
第20题:
public interface Person { } public class Employee extends Person { }
public interface Shape { } public class Employee extends Shape { }
public interface Color { } public class Employee extends Color { }
public class Species { } public class Animal (private Species species;)
interface Component { } Class Container implements Component ( Private Component[ ] children; )
第21题:
new Animal().soundOff();
Elephant e = new Alpha1();
Lion 1 = Alpha.get(“meat eater”);
new Alpha1().get(“veggie”).soundOff();
第22题:
0
1
2
3
第23题:
Cat is-a Animal
Cat is-a Jumper
Dog is-a Animal
Dog is-a Jumper
Cat has-a Animal
Beagle has-a Tail
Beagle has-a Jumper
第24题:
public class Employee implements Info extends Data { public void load(){/*dosomething*/} }
public class Employee extends Inf.implements Data{ public void load() {/*do something*/} }
public class Empl.yee implements Inf extends Data{ public void Data.1oad(){* do something*/} public void load(){/*do something*/} }
public class Employee extends Inf implements Data { public void Data.1oad() {/*do something*/) public void info.1oad(){/*do something*/} }