TOPIC 10 continued

1
TOPIC 10 continued
Arrays

• Arrays of objects

2
Declaring an array of objects

• Assume that the following Employee class is
  already created.
• public class Employee
• private int empNum
• private double empSalary
•  
• Employee(int num, double sal)
• empNum num
• empSalary sal

3

• public int getEmpNum()
• return empNum
•  
• public double getSalary()
• return empSalary

4

• You can create separate Employee objects with
  unique names, such as Employee painter,
  electrician, plumber, etc. but for many programs
  it is far more convenient to create an array of
  Employees.
• Employee emp new Employee7
• This statement reserves enough computer memory
  for seven Employee objects named emp0 through
  emp6, however, the statement does not actually
  construct those Employee objects, instead, you
  must call the seven individual constructors.

5

• The Employee constructor requires 2 arguments an
  employee number and salary. If you want to
  number your Employees 101, 102, etc. and start
  each Employee at a salary of R5.35.
• for (index 0 index lt emp.length index)
• empindex new Employee(101 index, 5.35)

6

• To use a method that belongs to an object that is
  part of an array, you insert the appropriate
  subscript notation after the array name and
  before the dot that precedes the method name.
• for (index 0 index lt emp.length index)
• System.out.println(empindex.getEmpNum()
• empindex.getSalary())