Question

Write a Java program that deals a five-card poker hand and then determines which of the following hands are contained in it: high card, pairs, two pair, three of a kind, flush. Test only for those hands. Use the numbers from 0 to 51 to represent the cards of the poker deck.

1. To deal the cards, your main method should call a secondary method that selects a random card. The secondary method should accept 5 integers that represent the cards that have been dealt already, or -1 if a card has not been dealt. It should return an integer for the new card, and it should avoid dealing duplicate cards. You can avoid dealing duplicate cards by first generating a random card, checking if it’s been dealt (i.e. it’s in the input) and then generating a new card. Use a loop to repeat.

2. Write five methods called highCardTest(), pairTest(), twoPairTest() , threeOfaKind(), and flush(), that each check the hand if it contains the corresponding poker hand. In other words, they should accept the 5 cards as input (return an error if not all cards are dealt), and they should return true if the hand can be found in the 5 input cards. They should return false otherwise.

3. Write a sixth method scoreHand() that tests the cards to determine what the highest possible hand is. It accepts all five cards as input. First test the flush. If the flush fails, test the three of a kind, in descending order of poker hand hierarchy. The highest hand that can be found should be found and returned as a string that describes the hand and the output, like “You have a diamond flush”.

4. Call the method scoreHand() in the main method, then ask the user if they’d like to score another random hand. Loop if the user answers “y”, quit if they answer “n”, and ask again if they answer anything else.

Answer 1

 import java.util.Arrays; import java.util.Scanner; public class Poker { private final static int NO_OF_CARDS = 5; /** * Counts the number of times card appears in the hand and returns it * Pre-condition : hand should be sorted * param hand * param card * return */ public static int countCard(int[] hand, int card) { int count = 0; for(int i = 0 ; i < NO_OF_CARDS ; i++) { if(hand[i] == card) count += 1; else { if(count > 0) //If a match is already found and the card in hand does not match the card break break; //because the hand array is sorted and all cards with same value will be in the order } } return count; } /** * Checks if a hand contains a pair * Pre-condition : hand should be sorted * param hand * return */ public static boolean containsPair(int hand[]) { for(int i = 0 ; i < NO_OF_CARDS ; i++) { if(countCard(hand, hand[i]) == 2) return true; } return false; } /** * Checks if a hand contains two pair * Pre-condition : hand should be sorted * param hand * return */ public static boolean containsTwoPair(int hand[]) { boolean pairOne = false; boolean pairTwo = false; for(int i = 0 ; i < NO_OF_CARDS ; i++) { if(pairOne && pairTwo) //If both pairs are found, return true return true; if(countCard(hand, hand[i]) == 2) { if(!pairOne) pairOne = true; else if(!pairTwo) pairTwo = true; } } return false; } /** * Checks if a hand contains 3 matching cards * Pre-condition : hand should be sorted * param hand * return */ public static boolean containsThreeOfaKind(int hand[]) { for(int i = 0 ; i < NO_OF_CARDS ; i++) { if(countCard(hand, hand[i]) == 3) return true; } return false; } /** * Checks if a hand contains a pair and 3 matching cards * Pre-condition : hand should be sorted * param hand * return */ public static boolean containsFullHouse(int hand[]) { boolean pair = false; boolean threeCards = false; for(int i = 0 ; i < NO_OF_CARDS ; i++) { if(pair && threeCards) //If a pair and 3 matching cards are found, return true return true; if(countCard(hand, hand[i]) == 2) pair = true; if(countCard(hand, hand[i]) == 3) threeCards = true; } return false; } /** * Checks if a hand contains 4 matching cards * Pre-condition : hand should be sorted * param hand * return */ public static boolean containsFourOfaKind(int hand[]) { for(int i = 0 ; i < NO_OF_CARDS ; i++) { if(countCard(hand, hand[i]) == 4) return true; } return false; } /** * Checks if a hand contains card values in order * Pre-condition : hand should be sorted * param hand * return */ public static boolean containsStraight(int hand[]) { for(int i = 1 ; i < NO_OF_CARDS ; i++) { if((hand[i] - hand[i - 1]) != 1) return false; } return true; } public static void main(String[] args) { int[] hand = new int[NO_OF_CARDS]; //Array to hold cards Scanner input = new Scanner(System.in); //Read input from keyboard System.out.println("Enter five numeric cards, no face cards. Use 2 - 9."); for(int i = 0 ; i < NO_OF_CARDS ; i++) { while(true) { System.out.println("Card " + (i + 1) + ": "); hand[i] = input.nextInt(); //Clear keyboard buffer input.nextLine(); if((1 < hand[i]) && (hand[i] < 10)) break; else System.out.println("Invalid input. Please try again."); } } //Close scanner input.close(); //Sort the input array Arrays.sort(hand); //Check poker hand if(containsStraight(hand)) //STRAIGHT System.out.println("Straight!"); else { if(containsFourOfaKind(hand)) //FOUR OF A KIND System.out.println("Four of a kind!"); else { if(containsFullHouse(hand)) //FULL HOUSE System.out.println("Full House!"); else { if(containsThreeOfaKind(hand)) //THREE OF A KIND System.out.println("Three of a kind!"); else { if(containsTwoPair(hand)) //TWO PAIR System.out.println("Two pair!"); else { if(containsPair(hand)) //PAIR System.out.println("Pair!"); else //HIGH CARD System.out.println("High Card!"); } } } } } } } /*SAMPLE OUTPUT: Enter five numeric cards, no face cards. Use 2 - 9. Card 1: 3 Card 2: 4 Card 3: 3 Card 4: 4 Card 5: 3 Full House!*/

you can put it in a loop to continusly take a input and to produce output.

Hope this helps...!