Question

3. Define a class License. A License has a license number and an suggest using java.time.LocalDate, but there are other possibilities). Then do the following: expiration date ( (a) Think what it might mean for two License instances to represent the same real- world license. Write the Boolean equals method that takes another License as argument and returns true if the two Licenses are "equal" in this sense. The block comment for your method should explain how you are doing the comparison. (b) Write a Boolean method expired that returns true if the current date is after the expiration date of the License, otherwise false. (c) Define the class DriversLicense as a subclass of License. In addition to the properties of a License, a DriversLicense also has the state that issued the license (you can use a string for this). (d) Suppose that driver's licenses from different states may have the same license number. Override the equals method for DriversLicense to do the right thing when testing if two DriversLicenses are equal. (e) Define the class TruckDriversLicense that extends DriversLicense. Override the toString method to return a meaningful description of an instance. (f) Define the class FishingLicense which extends License. In addition to the properties of a License, a FishingLicense specifies what types of may be caught (you can use a string for this). Override the toString method. Illustrate all of these with a main method in a separate test class.

Answer 1

1.

package License;

import java.util.Date;

public class License {
private String _LicenseNo ;
private Date _ExpiryDate ;
  
/**
*
* @param LicNo
* @param ExpDate
*/
public License(String LicNo,Date ExpDate)
{
this._LicenseNo = LicNo;
this._ExpiryDate = ExpDate;
}
  
public String getLicenseNo()
{
return this._LicenseNo;
}
  
public Date getExpiryDate()
{
return this._ExpiryDate;
}
  
public Boolean Expired()
{
if( new Date().after(_ExpiryDate))
{
return true;
}
return false;
}
/*
Check the current instance license number with passed license instance
if equal then returns true otherwise return false
*/
public Boolean equals(License lic)
{
if(lic.getLicenseNo().equals(this._LicenseNo))
{
return true;
}
return false;
}
  
public String toString()
{
return "License No :"+this._LicenseNo+", ExpiryDate : "+this._ExpiryDate;
}
  
  
}

2.

package License;

import java.util.Date;

public class DriversLicense extends License {
private String _State;
public DriversLicense(String LicNo, Date ExpDate, String State) {
super(LicNo, ExpDate);
this._State = State;
}
@Override
public Boolean equals(License lic)
{
if((this._State.equals(((DriversLicense)lic)._State)) && (this.getLicenseNo().equals(lic.getLicenseNo())))
{
return true;
}
return false;
}
  
public String getState()
{
return this._State;
}
  
public String toString()
{
return "License No:"+this.getLicenseNo()+", State : "+this._State+", ExpiryDate :"+this.getExpiryDate();
}
}

3.

package License;

import java.util.Date;

public class TruckDriversLicense extends DriversLicense {
  
public TruckDriversLicense(String LicNo, Date ExpDate, String State) {
super(LicNo, ExpDate, State);
}
@Override
public String toString()
{
return "Truck Drivers License No:"+this.getLicenseNo()+", State : "+this.getState()+", ExpiryDate :"+this.getExpiryDate();
}
}

4.

package License;

import java.util.Date;

/**
*
* @author Gajendra
*/
public class FishingLicense extends License {
private String _Type;

public FishingLicense(String LicNo, Date ExpDate, String Type) {
super(LicNo, ExpDate);
this._Type =Type;
}
  
@Override
public String toString()
{
return "Fishing License No:"+this.getLicenseNo()+", Type : "+this._Type+", ExpiryDate :"+this.getExpiryDate();
}
  
}

5.

package License;

import java.util.Date;

public class LicenseTest {

public static void main(String[] args) {
Date d1 = new Date();

License l1 = new License("001", d1);
License l2 = new License("002", d1);
System.out.println(l1.equals(l2));
License l3 = new License("001", d1);
System.out.println(l1.equals(l3));

TruckDriversLicense t1 = new TruckDriversLicense("0001", d1, "MP");
TruckDriversLicense t2 = new TruckDriversLicense("0001", d1, "MP");
System.out.println(t1.equals(t2));
TruckDriversLicense t3 = new TruckDriversLicense("0001", d1, "UP");
System.out.println(t1.equals(t3));
System.out.println(t1.toString());
  
FishingLicense f1 = new FishingLicense("0001", d1, "Fish");
System.out.println(f1.toString());
  
}
}

output:

run:
false
true
true
false
Truck Drivers License No:0001, State : MP, ExpiryDate :Sun Jun 09 13:47:21 IST 2019
Fishing License No:0001, Type : Fish, ExpiryDate :Sun Jun 09 13:47:21 IST 2019
BUILD SUCCESSFUL (total time: 1 second)