
Database System Concepts
7th Edition
ISBN: 9780078022159
Author: Abraham Silberschatz Professor, Henry F. Korth, S. Sudarshan
Publisher: McGraw-Hill Education
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Transcribed Image Text:Given the following definitions:
public abstract class Manager extends Employee {...}
public class Executive extends Manager { ... }
What, if anything, is wrong with the following code?
public class hrSystem {
}
public void payRaise () {
}
Manager m = new Manager();
O Compiler error because there is no Manager constructor.
Compiler error because Manager is abstract so an instance cannot be created.
No problem. The code will compile without any errors.
O Compiles fine but will generate a run-time error unless an Employee object is created first.
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- 15. Suppose the class Employee is declared as follows: public class Employee { private String name; private double baseSalary: public void setName(String newName) {...} public void setBasSalary(double newSalary){...} public String getName() {...} public double getSalary({...} } a)Declare a class Manager that inherits from the class Employee and adds an instance variable bonus for storing a salary bonus. Omit constructors and methods. ANS: b) Which instance variables does the Manager class have? c) In the manager class, provide the method overrides the getSalary method from the class Employee so that it returns the sum of the salary and the bonus d) Based on the above question, which methods does the manager class inherit? e) In the manager class, override the getName method so that managers have a before their name (such as *John Smith).arrow_forwardQuestion 1 Consider: class Car { ? } public Car() { } What happens if you try to run new Car(); A new object is created A new class is created It does not run Nothing happensarrow_forwardSubclasses of abstract classes must implement the parent class's abstract methods. You think?arrow_forward
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