1. public class Outer{ 2. public void someOuterMethod() { 3. // Line 3 4. } 5. public class Inner{} 6. public static void main( String[]argv ) { 7. Outer o = new Outer(); 8. // Line 8 9. } 10. } Which instantiates an instance of Inner?()
1. public class A { 2. void A() { 3. System.out.println(“Class A”); 4. } 5. public static void main(String[] args) { 6. new A(); 7. } 8. } What is the result?() A、 Class AB、 Compilation fails.C、 An exception is thrown at line 2.D、 An exception is thrown at line 6.E、 The code executes with no output.
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Which three demonstrate an “is a” relationship?() A、 public class X { } public class Y extends X { }B、 public interface Shape { } public interface Rectangle extends Shape{ }C、 public interface Color { } public class Shape { private Color color; }D、 public interface Species { } public class Animal { private Species species; }E、 public class Person { } public class Employee { public Employee(Person person) { }F、 interface Component { } class Container implements Component { private Component[] children; }
interface Data { public void load(); } 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() { /*dsomething */ } public void load() { /*do something */ } }E、 public class Employee implements Info extends Data { public void load() { /*do something */ } public void Info.load(){ /*do something*/ } }F、 public class Employee extends Info implements Data{ public void Data.load() { /*do something*/ } public void Info.load() { /*do something*/ } }
Which two allow the class Thing to be instantiated using new Thing()?A、 public class Thing { }B、 public class Thing { public Thing() {} }C、 public class Thing { public Thing(void) {} }D、 public class Thing { public Thing(String s) {} }E、 public class Thing { public void Thing() {} public Thing(String s) {} }
Which the two demonstrate an “is a” relationship?()A、 public interface Person {} Public class Employee extends Person {}B、 public interface Shape {} public interface Rectangle extends Shape {}C、 public interface Color {} public class Shape { private Color color; }D、 public class Species {} public class Animal { private Species species; }E、 interface Component {} Class Container implements Component {private Component [] children;
Which two demonstrate an “is a” relationship?() A、 public interface Person { } public class Employee extends Person { }B、 public interface Shape { } public class Employee extends Shape { }C、 public interface Color { } public class Employee extends Color { }D、 public class Species { } public class Animal (private Species species;)E、 interface Component { } Class Container implements Component ( Private Component[ ] children; )
What produces a compiler error?() A、 class A { public A(int x) {} }B、 class A {} class B extends A { B() {} }C、 class A { A() {} } class B { public B() {} }D、 class Z { public Z(int) {} } class A extends Z {}