Related Questions

Which of the following is/are true for an abstract class?
1. A class is declared abstract by prefacing the definition with the word abstract.
2. A class is declare abstract by using the keyword implements.
3. It is a class that really isn’t supposed to ever be instantiated but instead serves as a base class.
4. Attempting to instantiate an abstract class results in an error.
Which of the following is/are true for an abstract class? i) Abstract classes in PHP are declared with the help of abstract keyword. ii) A class is declare abstract by using the keyword implements. iii) It is a class that really isn’t supposed to ever be instantiated but instead serves as a base class. iv) Attempting to instantiate an abstract class results in an error. 
interface Base{ boolean m1 (); byte m2(short s);}

which two code fragments will compile?
1. interface Base2 implements Base {}2. abstract class Class2 extends Base { public boolean m1(){ return true; }}3. abstract class Class2 implements Base {}4. abstract class Class2 implements Base { public boolean m1(){ return (7 > 4); }}5. abstract class Class2 implements Base { protected boolean m1(){ return (5 > 7) }}
Which two classes use the Shape class correctly?
A. public class Circle implements Shape { private int radius; }B. public abstract class Circle extends Shape { private int radius; }C. public class Circle extends Shape { private int radius; public void draw(); }D. public abstract class Circle implements Shape { private int radius; public void draw(); }E. public class Circle extends Shape { private int radius; public void draw() { /* code here */ } }F. public abstract class Circle implements Shape { private int radius; public void draw() { /* code here */ } }
Which two of the following are legal declarations for abstract classes and interfaces?
1. final abstract class Test {}
2. public static interface Test {}
3. final public class Test {}
4. protected abstract class Test {}
5. protected interface Test {}
6. abstract public class Test {}
Which of the following statements regarding static methods are correct?
1. Static methods are difficult to maintain, because you can not change their implementation.
2. Static methods can be called using an object reference to an object of the class in which this method is defined.
3. Static methods are always public, because they are defined at class-level.
4. Static methods do not have direct access to non-static methods which are defined inside the same class.
Abstract class A has 4 virtual functions. Abstract class B defines only 2 of those member functions as it extends class A. Class C extends class B and implements the other two member functions of class A. Choose the correct option below.
At least how many abstract methods must an abstract class contain?
h,J,K,L,M,N and O are the only legislators eligible to vote on Bills 1,2 and 3, each of which will be passed if at least four legislators eligible vote in favor of it. each legislator must vote on all three bills; on abstentions are possible. The following is known : *H must vote against all three bills; each of the other legislators must vote in favor of at least one bill and against at lest one bill. *j must vote against Bills 1. *O Must vote against Bills 2 and 3. * L must the same way that K dose on all three bills.*N must vote the same way that O dose on all three bills. which of the following must vote in favor of Bill 1 ?
h,J,K,L,M,N and O are the only legislators eligible to vote on Bills 1,2 and 3, each of which will be passed if at least four legislators eligible vote in favor of it. each legislator must vote on all three bills; on abstentions are possible. The following is known : *H must vote against all three bills; each of the other legislators must vote in favor of at least one bill and against at lest one bill. *j must vote against Bills 1. *O Must vote against Bills 2 and 3. * L must the same way that K dose on all three bills.*N must vote the same way that O dose on all three bills. If any bill is to be passed,which of the following must be among the legislators who vote in favor of it?