This document contains a Java program that evaluates a player's hand of five numeric cards (2-9) using various poker hand ranking rules. It prompts the user for input, sorts the cards using bubble sort, and determines the type of hand (like full house, straight, or pair). The program includes multiple helper methods to check for specific hand types based on the card values.

1. import java.util.Scanner;
public class Assignment4 {
public static void main(String args[]) {
final int LEN = 5;
int[] hand = new int[LEN];
Scanner input = new Scanner(System.in);
//input the hand
System.out.println("Enter five numeric cards, no face cards. Use 2-9.");
for (int i = 0; i < hand.length; i++) {
hand[i] = input.nextInt();
}
//sort the collection
bubbleSortCards(hand);
//determine players hand type
//flow of evaluation -> checking complex hands first
if (containsFullHouse(hand)) {
System.out.println("Full House!");
} else if (containsStraight(hand)) {
System.out.println("Straight!");
} else if (containsFourOfaKind(hand)) {
System.out.println("Four of a Kind!");
} else if (containsThreeOfaKind(hand)) {
System.out.println("Three of a Kind!");
} else if (containsTwoPair(hand)) {
System.out.println("Two Pair!");
} else if (containsPair(hand)) {
System.out.println("Pair!");
} else
System.out.println("High Card!");
}
//cardInSets is called with hand[] and pair to check if a pair is found.
public static boolean containsPair(int hand[]) {
int pair = 2;

2. return cardInSets(hand, pair) != NOT_FOUND;
}
//cardInSets is called with hand[] and pair to check if a pair is found.
//Then calls back again with fcard result to check for another pair.
public static boolean containsTwoPair(int hand[]) {
int pair = 2;
int fcard = cardInSets(hand, pair);
int scard = cardInSets(hand, pair, fcard);
return fcard!=NOT_FOUND && scard!=NOT_FOUND;
}
//cardInSets is called with hand[] and threeaKind to check if three of a kind has been found.
public static boolean containsThreeOfaKind(int hand[]) {
int threeaKind = 3;
return cardInSets(hand, threeaKind) != NOT_FOUND;
}
//hasStraight will resolve to true, unless the previous value++ is not equivalent.
//The loop ends as soon as hasStaight is false or the end of the hand is reached.
public static boolean containsStraight(int hand[]) {
boolean hasStraight = true;
int i=1;
do {
hasStraight = (hand[i] == (hand[i-1] + 1));
} while(hasStraight && ++i < hand.length);
return hasStraight;
}
//cardInSets is called with hand[] and threeKinds to check if three of a kind is found.
//Then calls back again with pair and tcard result to check for a pair of another card type.
public static boolean containsFullHouse(int hand[]) {
int threeKinds = 3;
int pair = 2;
int tcard = cardInSets(hand, threeKinds);
int pcard = cardInSets(hand, pair, tcard);
return tcard!=NOT_FOUND && pcard!=NOT_FOUND;
}
//cardInSets is called with hand[] and fouraKind to check if four of a kind is found.
public static boolean containsFourOfaKind(int hand[]) {

3. int fouraKind = 4;
return cardInSets(hand, fouraKind) != NOT_FOUND;
}
//When ignoreCard isn't needed, it overloads with a sentinel 0.
public static int cardInSets(int hand[], int numKinds) {
return cardInSets(hand, numKinds, 0);
}
//The method cardInSets is a generic evaluation that returns if the parameter specified
numKinds(like 2 for pair) has been found in the hand.
//The ignoreCard defaults to 0 through overloading, but is required for the fullhouse evalation.
//After the three of a kind is found, it passes that card value as ignoreCard to ensure the pair
evaluation will not be of the same card type.
public static int cardInSets(int hand[], int numKinds, int ignoreCard) {
numKinds--;
int last = hand[0];
int card=NOT_FOUND;
int numMatch = 0;
for (int i = 1; i < hand.length; i++) {
if (last == hand[i] && ignoreCard!=last) {
numMatch++;
//hasNumKinds = hasMatch==numKinds;
if (numMatch==numKinds) {
card=last;
break;
}
} else numMatch = NOT_FOUND;
last = hand[i];
}
return card;
}
//For ease of evaluation, the hand is sorted after input by bubble sort.
public static int[] bubbleSortCards(int hand[]) {
int temp;
for (int i=0; i < hand.length-1; i++) {

4. for (int j=1; j < hand.length-i; j++) {
if (hand[j-1] > hand[j]) {
temp = hand[j-1];
hand[j-1] = hand[j];
hand[j] = temp;
}
}
}
return hand;
}
}
Solution
import java.util.Scanner;
public class Assignment4 {
public static void main(String args[]) {
final int LEN = 5;
int[] hand = new int[LEN];
Scanner input = new Scanner(System.in);
//input the hand
System.out.println("Enter five numeric cards, no face cards. Use 2-9.");
for (int i = 0; i < hand.length; i++) {
hand[i] = input.nextInt();
}
//sort the collection
bubbleSortCards(hand);
//determine players hand type
//flow of evaluation -> checking complex hands first
if (containsFullHouse(hand)) {
System.out.println("Full House!");
} else if (containsStraight(hand)) {
System.out.println("Straight!");
} else if (containsFourOfaKind(hand)) {
System.out.println("Four of a Kind!");

5. } else if (containsThreeOfaKind(hand)) {
System.out.println("Three of a Kind!");
} else if (containsTwoPair(hand)) {
System.out.println("Two Pair!");
} else if (containsPair(hand)) {
System.out.println("Pair!");
} else
System.out.println("High Card!");
}
//cardInSets is called with hand[] and pair to check if a pair is found.
public static boolean containsPair(int hand[]) {
int pair = 2;
return cardInSets(hand, pair) != NOT_FOUND;
}
//cardInSets is called with hand[] and pair to check if a pair is found.
//Then calls back again with fcard result to check for another pair.
public static boolean containsTwoPair(int hand[]) {
int pair = 2;
int fcard = cardInSets(hand, pair);
int scard = cardInSets(hand, pair, fcard);
return fcard!=NOT_FOUND && scard!=NOT_FOUND;
}
//cardInSets is called with hand[] and threeaKind to check if three of a kind has been found.
public static boolean containsThreeOfaKind(int hand[]) {
int threeaKind = 3;
return cardInSets(hand, threeaKind) != NOT_FOUND;
}
//hasStraight will resolve to true, unless the previous value++ is not equivalent.
//The loop ends as soon as hasStaight is false or the end of the hand is reached.
public static boolean containsStraight(int hand[]) {
boolean hasStraight = true;
int i=1;
do {
hasStraight = (hand[i] == (hand[i-1] + 1));
} while(hasStraight && ++i < hand.length);

6. return hasStraight;
}
//cardInSets is called with hand[] and threeKinds to check if three of a kind is found.
//Then calls back again with pair and tcard result to check for a pair of another card type.
public static boolean containsFullHouse(int hand[]) {
int threeKinds = 3;
int pair = 2;
int tcard = cardInSets(hand, threeKinds);
int pcard = cardInSets(hand, pair, tcard);
return tcard!=NOT_FOUND && pcard!=NOT_FOUND;
}
//cardInSets is called with hand[] and fouraKind to check if four of a kind is found.
public static boolean containsFourOfaKind(int hand[]) {
int fouraKind = 4;
return cardInSets(hand, fouraKind) != NOT_FOUND;
}
//When ignoreCard isn't needed, it overloads with a sentinel 0.
public static int cardInSets(int hand[], int numKinds) {
return cardInSets(hand, numKinds, 0);
}
//The method cardInSets is a generic evaluation that returns if the parameter specified
numKinds(like 2 for pair) has been found in the hand.
//The ignoreCard defaults to 0 through overloading, but is required for the fullhouse evalation.
//After the three of a kind is found, it passes that card value as ignoreCard to ensure the pair
evaluation will not be of the same card type.
public static int cardInSets(int hand[], int numKinds, int ignoreCard) {
numKinds--;
int last = hand[0];
int card=NOT_FOUND;
int numMatch = 0;
for (int i = 1; i < hand.length; i++) {
if (last == hand[i] && ignoreCard!=last) {
numMatch++;
//hasNumKinds = hasMatch==numKinds;

7. if (numMatch==numKinds) {
card=last;
break;
}
} else numMatch = NOT_FOUND;
last = hand[i];
}
return card;
}
//For ease of evaluation, the hand is sorted after input by bubble sort.
public static int[] bubbleSortCards(int hand[]) {
int temp;
for (int i=0; i < hand.length-1; i++) {
for (int j=1; j < hand.length-i; j++) {
if (hand[j-1] > hand[j]) {
temp = hand[j-1];
hand[j-1] = hand[j];
hand[j] = temp;
}
}
}
return hand;
}
}