Class Lane

java.lang.Object
  Lane

public class Lane
extends java.lang.Object

This class represents one lane in a highway. It keeps track of all cars in a lane. This class was originally written for the third programming assignment in CS 302 at UW-Madison in Spring 2009 by the current author.

Author:

Dalibor Zeleny (dalibor@cs.wisc.edu)

Constructor Summary

Lane()
Default (and only) constructor

Method Summary

void	addCar(Car car) Adds car to this lane.
void	addCoin(Coin co) Adds co to this lane.
boolean	canFitCar(Car car) Determines whether the car in the parameter can go in this lane.
Car	getNextCar() Returns a reference to the car pointed to by the iterator for cars.
Coin	getNextCoin() Returns a reference to the coin pointed to by the iterator for coins.
int	getNumCars() Returns the number of cars in this lane
int	getNumCoins() Returns the number of coins in this lane
boolean	hasNextCar() Checks whether the iterator for cars in this lane has reached the end of the list of cars
boolean	hasNextCoin() Checks whether the iterator for coins in this lane has reached the end of the list of coins
Car	lookAtNextCar() Returns a reference to the car pointed to by the iterator for cars.
Coin	lookAtNextCoin() Returns a reference to the coin pointed to by the iterator for coins.
Car	removeCar(Car car) Removes car from this lane, and returns a reference to it.
Coin	removeCoin(Coin co) Removes co from this lane, and returns a reference to it.
void	rewind() Resets the iterators for this lane.
java.lang.String	toString() Returns a String description of the current lane.

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, wait, wait, wait

Constructor Detail

Lane

public Lane()

Default (and only) constructor

Method Detail

canFitCar

public boolean canFitCar(Car car)

Determines whether the car in the parameter can go in this lane. This is done by comparing car's distance with the distances of other cars in this lane, taking lengths into account.

Parameters:

car - The car that's trying to fit in this lane

Returns:

whether the car can fit in the lane

addCar

public void addCar(Car car)

Adds car to this lane. This method does not attempt to verify that there is space for car in this lane. The user can verify there is room by calling the canFitCar() method.

Parameters:

car - the car we're adding to this lane.

rewind

public void rewind()

Resets the iterators for this lane. That is, after calling this method, the next call to getNextCar() or lookAtNextCar() will return a reference to the first car in this lane. Similarly, the next call to getNextCoin() or lookAtNextCoin() will return a reference to the first coin in this lane. The cars and coins are visited by the iterator in descending order of the return value of the getPositionOfFront() method.

hasNextCar

public boolean hasNextCar()

Checks whether the iterator for cars in this lane has reached the end of the list of cars

Returns:

true if there are cars left, false otherwise

lookAtNextCar

public Car lookAtNextCar()

Returns a reference to the car pointed to by the iterator for cars. This method does not advance the iterator.

Returns:

reference to the car pointed to by the iterator for cars

getNextCar

public Car getNextCar()

Returns a reference to the car pointed to by the iterator for cars. This method advances the iterator after each call.

Returns:

reference to the car pointed to by the iterator for cars

hasNextCoin

public boolean hasNextCoin()

Checks whether the iterator for coins in this lane has reached the end of the list of coins

Returns:

true if there are coins left, false otherwise

lookAtNextCoin

public Coin lookAtNextCoin()

Returns a reference to the coin pointed to by the iterator for coins. This method does not advance the iterator.

Returns:

reference to the coin pointed to by the iterator for coins

getNextCoin

public Coin getNextCoin()

Returns a reference to the coin pointed to by the iterator for coins. This method advances the iterator after each call.

Returns:

reference to the coin pointed to by the iterator for coins

addCoin

public void addCoin(Coin co)

Adds co to this lane. Unlike with cars, we don't care if coins overlap.

Parameters:

co - the coin we're adding to this lane.

removeCar

public Car removeCar(Car car)

Removes car from this lane, and returns a reference to it. If the car isn't found in this lane, return null.

Parameters:

car - The car to remove

Returns:

reference to the removed car or null if the car was not removed

removeCoin

public Coin removeCoin(Coin co)

Removes co from this lane, and returns a reference to it. If the coin isn't found in this lane, return null.

Parameters:

co - The coin to remove

Returns:

reference to the removed object or null if it was not removed

getNumCars

public int getNumCars()

Returns the number of cars in this lane

Returns:

the number of cars in this lane

getNumCoins

public int getNumCoins()

Returns the number of coins in this lane

Returns:

the number of coins in this lane

toString

public java.lang.String toString()

Returns a String description of the current lane. The string contains information about each car, with one car per line, and about each coin, with one object per line. Here is an example of the output. CAR 0: ID: 41, distance: 1098.5299999999847, velocity: 33.0, length: 4.0; driven by Bob who prefers 33.0 CAR 1: ID: 35, distance: 1042.9299999999862, velocity: 43.0, length: 3.75; driven by Bob who prefers 43.0 CAR 2: ID: 31, distance: 1008.4099999999748, velocity: 56.0, length: 3.75; driven by Bob who prefers 56.0 CAR 3: ID: 4, distance: 845.9199999999934, velocity: 66.0, length: 3.5; driven by Bob who prefers 66.0 CAR 4: ID: 2, distance: 563.2399999999914, velocity: 52.0, length: 5.75; driven by Bob who prefers 52.0 COIN 0: ID: 3, at distance: 955.850000000004 with score bonus 796(-12 decrease), time bonus 6.300000000000006(-0.1 decrease) and decrease period 5. It has lived 88 out of 400 ticks

Overrides:

toString in class java.lang.Object

Returns:

String description of the current lane.