Question

How can the java code be edited that when someone exits the lot, they receive an exiting timestamp. And also i would need that exit timestamp to be subtracted from the timestamp the driver gets when entering the lot to find out the total amount of time they were in the parking lot. please explain. should only need a couple of lines added.

//////////////////////////////ParkingCarInfo.java///////////////////////////////////////////

package test;

import java.sql.Timestamp;

//Class: ParkingCarInfo
public class ParkingCarInfo {
private String name; //name
private Timestamp timestamp; //timestamp

//constructor
public ParkingCarInfo(String name){
this.name = name;
//create a new timestamp for current time
this.timestamp = new Timestamp(System.currentTimeMillis());
}

public String getName() {
return name;
}

public void setName(String name) {
this.name = name;
}

public Timestamp getTimestamp() {
return timestamp;
}

public void setTimestamp(Timestamp timestamp) {
this.timestamp = timestamp;
}

@Override
//toString method
public String toString() {
return "ParkingCarInfo [name=" + name + ", timestamp=" + timestamp + "]";
}
}

//////////////////////////TestParking.java///////////////////////////////////////

package test;

import java.util.LinkedList;
import java.util.Scanner;

public class TestParking {

public static void main(String[] args) {
ParkingLot pl = new ParkingLot(5);
Scanner sc = new Scanner(System.in);
System.out.println("Capacity of parking lot = " + pl.getCapacity());

  
String name;

for(int j=0;j<10;j++) {

System.out.println("\nEnter 'exit' to Exit the Parking System");
System.out.println("Attempt to park! Enter name:");
name = sc.nextLine();

if(name.compareToIgnoreCase("exit")==0) {
System.out.println("\nThe number of cars parked at this moment : " + pl.getSize());
System.out.println("Exiting the Parking System");
break;
}
LinkedList<ParkingCarInfo> info = pl.getCars();
boolean flag = true;
for (int i = 0; i < info.size(); i++) {

if (info.get(i).getName().compareTo(name) == 0) {
pl.leaveFromParking(info.get(i));
flag = false;
break;
}
}

if (flag)
pl.parkACar(name);

System.out.println("\nThe number of cars parked at this moment : " + pl.getSize());

  

}

sc.close();
}

}
//////////////////////ParkingLot.java//////////////////////////

package test.parkinglot;

import java.util.LinkedList;
//Class: ParkingLot
public class ParkingLot {
//the linked list will hold all ParkingCarInfo currently parked
private LinkedList<ParkingCarInfo> cars = null;
private int size = 0; //number of currently parked cars
private int capacity = 0; //maximum capacity of parking lot
  
//constructor
public ParkingLot(int capacity){
this.capacity = capacity;
this.cars = new LinkedList<ParkingCarInfo>();
this.size = 0;
}
  
  
//getter for cars
public LinkedList<ParkingCarInfo> getCars() {
return cars;
}

//getter for size
public int getSize() {
return size;
}

//getter for capacity
public int getCapacity() {
return capacity;
}

/**
* Park a Car method with the given name
* @param name
*/
public void parkACar(String name){
if(this.size == this.capacity){ //if max capacity is filled
System.out.println("Parking Lot is already full. The car cannot be admitted!");
}else{ //otherwise if there is space left for parking
ParkingCarInfo parkingCar = new ParkingCarInfo(name); //create a ParkingCarInfo instance
cars.add(parkingCar); //add it to cars
System.out.println("A new car is parked..");
System.out.println(parkingCar);
this.size++; //increase the size
}
  
}
  
/**
* method to handle the situation when a car leaves the parking
* @param pc
*/
public void leaveFromParking(ParkingCarInfo pc){
boolean isLeft = cars.remove(pc); //if Car with given ParkingCarInfo, leaves
if(isLeft){ //if successful
this.size--;//cecrease the size
System.out.println("The car having "+pc+" has left the parking lot.");
}else{
System.out.println("Sorry! No Parking info for the car is found.");
}
  
}
  
}

Answer 1

The code in bold are the lines which are added

Code:

package test;

import java.sql.Timestamp;

//Class: ParkingCarInfo
public class ParkingCarInfo {
private String name; //name
private Timestamp timestamp; //timestamp

//constructor
public ParkingCarInfo(String name){
this.name = name;
//create a new timestamp for current time
this.timestamp = new Timestamp(System.currentTimeMillis());
}

public String getName() {
return name;
}

public void setName(String name) {
this.name = name;
}

public Timestamp getTimestamp() {
return timestamp;
}

public void setTimestamp(Timestamp timestamp) {
this.timestamp = timestamp;
}

@Override
//toString method
public String toString() {
return "ParkingCarInfo [name=" + name + ", timestamp=" + timestamp + "]";
}
}

//////////////////////////TestParking.java///////////////////////////////////////

package test;

import java.util.LinkedList;
import java.util.Scanner;

public class TestParking {

public static void main(String[] args) {
ParkingLot pl = new ParkingLot(5);
Scanner sc = new Scanner(System.in);
System.out.println("Capacity of parking lot = " + pl.getCapacity());

  
String name;

for(int j=0;j<10;j++) {

System.out.println("\nEnter 'exit' to Exit the Parking System");
System.out.println("Attempt to park! Enter name:");
name = sc.nextLine();

if(name.compareToIgnoreCase("exit")==0) {
System.out.println("\nThe number of cars parked at this moment : " + pl.getSize());
System.out.println("Exiting the Parking System");
break;
}
LinkedList<ParkingCarInfo> info = pl.getCars();
boolean flag = true;
for (int i = 0; i < info.size(); i++) {

if (info.get(i).getName().compareTo(name) == 0) {
pl.leaveFromParking(info.get(i));
flag = false;
break;
}
}

if (flag)
pl.parkACar(name);

System.out.println("\nThe number of cars parked at this moment : " + pl.getSize());

  

}

sc.close();
}

}
//////////////////////ParkingLot.java//////////////////////////

package test.parkinglot;

import java.util.LinkedList;
//Class: ParkingLot
public class ParkingLot {
//the linked list will hold all ParkingCarInfo currently parked
private LinkedList<ParkingCarInfo> cars = null;
private int size = 0; //number of currently parked cars
private int capacity = 0; //maximum capacity of parking lot

  
//constructor
public ParkingLot(int capacity){
this.capacity = capacity;
this.cars = new LinkedList<ParkingCarInfo>();
this.size = 0;
}
  
  
//getter for cars
public LinkedList<ParkingCarInfo> getCars() {
return cars;
}

//getter for size
public int getSize() {
return size;
}

//getter for capacity
public int getCapacity() {
return capacity;
}

/**
* Park a Car method with the given name
* @param name
*/
public void parkACar(String name){
if(this.size == this.capacity){ //if max capacity is filled
System.out.println("Parking Lot is already full. The car cannot be admitted!");
}else{ //otherwise if there is space left for parking
ParkingCarInfo parkingCar = new ParkingCarInfo(name); //create a ParkingCarInfo instance
cars.add(parkingCar); //add it to cars
System.out.println("A new car is parked..");
System.out.println(parkingCar);
this.size++; //increase the size
}
  
}
  
/**
* method to handle the situation when a car leaves the parking
* @param pc
*/
public void leaveFromParking(ParkingCarInfo pc){
boolean isLeft = cars.remove(pc); //if Car with given ParkingCarInfo, leaves
//Calculate the elapsed time in the parking lot
long timeDiff = System.currentTimeMillis() - pc.getTimestamp().getTime();
if(isLeft){ //if successful
this.size--;//cecrease the size
System.out.println("The car having "+pc+" has left the parking lot. total time in parking lot is "+timeDiff+" milliseconds");
}else{
System.out.println("Sorry! No Parking info for the car is found.");
}
  
}
  
}