7 Replies Latest reply: Mar 1, 2013 11:44 AM by 939520 RSS

    Java Classes

    987741
      Hi,

      I am new to Java, so excuse if this question is real basic:

      I have 3 questions.

      Write a Java class called Person which describes a person with these properties:
      - First Name
      - Last Name
      - Age

      Write a Java class which describes a company employee which uses the Person class above and adds two extra properties:
      - Position
      - Join Date

      Write a Java class called Company which contains
      - One or more employees
      - Business type


      I know how to do the first one:

      public class Person {

      String fName;
      String lName;
      int age;
      }

      But I am very trouble with the last two, please can someone help

      Thank you
        • 1. Re: Java Classes
          Kayaman
          984738 wrote:
          But I am very trouble with the last two, please can someone help
          Do you know how to extend a class? That's the key for the second question.

          For the third question, you are probably meant to use an array of employees.

          Good luck.
          • 2. Re: Java Classes
            987741
            public class describe extends Person {

            String Position;
            int jDate;
            }

            Is this how the second question is done?
            • 3. Re: Java Classes
              Kayaman
              984738 wrote:
              public class describe extends Person {

              String Position;
              int jDate;
              }

              Is this how the second question is done?
              Well, I certainly wouldn't call a class "describe". Would you say "my company has many describes working there"? Of course not.

              But yes, extends is the keyword for creating a subclass.
              • 4. Re: Java Classes
                994177
                public class Person {
                     
                     String firstName;
                     String lastName;
                     int age;
                     
                     public Person() {
                          super();
                     }

                     public Person(String firstName, String lastName, int age) {
                          this.firstName = firstName;
                          this.lastName = lastName;
                          this.age = age;
                     }
                     
                     public String getFirstName() {
                          return firstName;
                     }
                     public void setFirstName(String firstName) {
                          this.firstName = firstName;
                     }
                     public String getLastName() {
                          return lastName;
                     }
                     public void setLastName(String lastName) {
                          this.lastName = lastName;
                     }
                     public int getAge() {
                          return age;
                     }
                     public void setAge(int age) {
                          this.age = age;
                     }
                     
                }

                ------------------------------------------------------------------------------------------
                import java.util.Date;

                public class Employee extends Person {
                     
                     String position;
                     Date joiningDate;

                     public Employee() {
                          super();
                     }

                     public Employee(String position, Date joiningDate) {
                          this.position = position;
                          this.joiningDate = joiningDate;
                     }

                     public String getPosition() {
                          return position;
                     }
                     public void setPosition(String position) {
                          this.position = position;
                     }
                     public Date getJoiningDate() {
                          return joiningDate;
                     }
                     public void setJoiningDate(Date joiningDate) {
                          this.joiningDate = joiningDate;
                     }
                     
                }
                ---------------------------------------------------------------------------------

                import java.util.List;

                public class Company {
                     
                     List<Employee> employees;
                     String businessType;
                     
                     public Company() {
                          super();
                     }

                     public List<Employee> getEmployees() {
                          return employees;
                     }

                     public void setEmployees(List<Employee> employees) {
                          this.employees = employees;
                     }
                     public String getBusinessType() {
                          return businessType;
                     }
                     public void setBusinessType(String businessType) {
                          this.businessType = businessType;
                     }
                     
                }
                • 5. Re: Java Classes
                  994177
                  public class Person {
                       
                       String firstName;
                       String lastName;
                       int age;
                       
                       public Person() {
                            super();
                       }

                       public Person(String firstName, String lastName, int age) {
                            this.firstName = firstName;
                            this.lastName = lastName;
                            this.age = age;
                       }
                       
                       public String getFirstName() {
                            return firstName;
                       }
                       public void setFirstName(String firstName) {
                            this.firstName = firstName;
                       }
                       public String getLastName() {
                            return lastName;
                       }
                       public void setLastName(String lastName) {
                            this.lastName = lastName;
                       }
                       public int getAge() {
                            return age;
                       }
                       public void setAge(int age) {
                            this.age = age;
                       }
                       
                  }

                  ------------------------------------------------------------------------------------------
                  import java.util.Date;

                  public class Employee extends Person {
                       
                       String position;
                       Date joiningDate;

                       public Employee() {
                            super();
                       }

                       public Employee(String position, Date joiningDate) {
                            this.position = position;
                            this.joiningDate = joiningDate;
                       }

                       public String getPosition() {
                            return position;
                       }
                       public void setPosition(String position) {
                            this.position = position;
                       }
                       public Date getJoiningDate() {
                            return joiningDate;
                       }
                       public void setJoiningDate(Date joiningDate) {
                            this.joiningDate = joiningDate;
                       }
                       
                  }
                  ---------------------------------------------------------------------------------

                  import java.util.List;

                  public class Company {
                       
                       List<Employee> employees;
                       String businessType;
                       
                       public Company() {
                            super();
                       }

                       public List<Employee> getEmployees() {
                            return employees;
                       }

                       public void setEmployees(List<Employee> employees) {
                            this.employees = employees;
                       }
                       public String getBusinessType() {
                            return businessType;
                       }
                       public void setBusinessType(String businessType) {
                            this.businessType = businessType;
                       }
                       
                  }
                  • 6. Re: Java Classes
                    994177
                    public class Person {
                         
                         String firstName;
                         String lastName;
                         int age;
                         
                         public Person() {
                              super();
                         }

                         public Person(String firstName, String lastName, int age) {
                              this.firstName = firstName;
                              this.lastName = lastName;
                              this.age = age;
                         }
                         
                         public String getFirstName() {
                              return firstName;
                         }
                         public void setFirstName(String firstName) {
                              this.firstName = firstName;
                         }
                         public String getLastName() {
                              return lastName;
                         }
                         public void setLastName(String lastName) {
                              this.lastName = lastName;
                         }
                         public int getAge() {
                              return age;
                         }
                         public void setAge(int age) {
                              this.age = age;
                         }
                         
                    }

                    ------------------------------------------------------------------------------------------

                    import java.util.Date;

                    public class Employee extends Person {
                         
                         String position;
                         Date joiningDate;

                         public Employee() {
                              super();
                         }

                         public Employee(String position, Date joiningDate) {
                              this.position = position;
                              this.joiningDate = joiningDate;
                         }

                         public String getPosition() {
                              return position;
                         }
                         public void setPosition(String position) {
                              this.position = position;
                         }
                         public Date getJoiningDate() {
                              return joiningDate;
                         }
                         public void setJoiningDate(Date joiningDate) {
                              this.joiningDate = joiningDate;
                         }
                         
                    }

                    ------------------------------------------------------------------------------------------

                    import java.util.List;

                    public class Company {
                         
                         List<Employee> employees;
                         String businessType;
                         
                         public Company() {
                              super();
                         }

                         public List<Employee> getEmployees() {
                              return employees;
                         }

                         public void setEmployees(List<Employee> employees) {
                              this.employees = employees;
                         }
                         public String getBusinessType() {
                              return businessType;
                         }
                         public void setBusinessType(String businessType) {
                              this.businessType = businessType;
                         }
                         
                    }
                    • 7. Re: Java Classes
                      939520
                      I think it may be a good idea to avoid giving complete answers to homework questions. The student needs to reason through the assignment on his own and exercise is gray matter.