Which of the following statements regarding abstract methods are true?
A. Abstract classes have constructors.
B. A class that contains abstract methods must be abstract.
C. It is possible to declare an abstract class that contains no abstract methods.
D. An abstract method cannot be contained in a nonabstract class.
E. A data field can be declared abstract.
The correct answer is ABCD
Java
- In Java, the mechanism that allows you to combine data and operations on the data into a single unit is called a(n)
- Which of the following is a legal way to declare and instantiate an array of 10 Strings?
- The statement System.out.println(values[7]); will
- Which of the following loops would adequately add 1 to each element stored in values?
- What is the value of values.length?
- What is returned by values[3]?
- A listener is an object that
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- In order to have some code throw an exception, you would use which of the following reserved words?
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- Static methods cannot
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- The return statement must be followed a single variable that contains the value to be returned.