Birds.java

public class Birds {

	static int numberOfBirdTypes = 0;
	static String[][] birds = new String[numberOfBirdTypes][4];

	public static void main(String[] args) {

		printBirdInfo();  // array is empty

		addBirdType("Eagle"); // initializing
		printBirdInfo("Eagle");
		setPrice("Eagle", 5);
		printBirdInfo("Eagle");
		addBirds("Eagle", 20);
		printBirdInfo("Eagle");

		addBirdType("Duck");
		setPrice("Duck", 2);
		addBirds("Duck", 10);
		printBirdInfo("Duck");

		addBirdType("Duck"); // once again

		addBirdType("Woodpecker");
		setPrice("Woodpecker", 30);
		addBirds("Woodpecker", 5);
		printBirdInfo("Woodpecker");

		sellBirds("Eagle", 18);
		printBirdInfo("Eagle");

		sellBirds("Duck", 8);
		printBirdInfo("Duck");

		sellBirds("Woodpecker", 100);
		printBirdInfo("Woodpecker");

		printBirdInfo("hgcihgcgh");

		System.out.println("Birds sold totally: " + calcBirdsSoldTotally());

		System.out.println("Profit: $" + calcProfit());

		System.out.println("Birds less than 3: " + findBirdsLessThan3());

		System.out.println("Birds total: " + birdsTotal());

		printBirdInfo();

	}

	static void addBirdType(String birdType) {

		for (String[] i : birds) {
			if (i[0].equals(birdType)) {
				System.out.println("This bird type already exists!");
				return;
			}
		}

		numberOfBirdTypes ++;
		String[][] birdsNew = new String[numberOfBirdTypes][4];

		for (int i = 0; i < birds.length; i++) {
			birdsNew[i][0] = birds[i][0];
			birdsNew[i][1] = birds[i][1];
			birdsNew[i][2] = birds[i][2];
			birdsNew[i][3] = birds[i][3];
		}

		birdsNew[birds.length][0] = birdType;
		birdsNew[birds.length][1] = "0";
		birdsNew[birds.length][2] = null;
		birdsNew[birds.length][3] = "0";

		birds = birdsNew;

	}

	static int getBirdIndex(String birdType) {
		for (int i = 0; i < birds.length; i++) {
			if (birds[i][0].equals(birdType)) {
				return i;
			}
		}

		System.out.println("There is no such bird type!");
		return -1;
	}

	static void setPrice(String birdType, int price) {
		int i = getBirdIndex(birdType);
		birds[i][2] = String.valueOf(price);
	}

	static void addBirds(String birdType, int num) {
		int i = getBirdIndex(birdType);
		birds[i][1] = String.valueOf(Integer.valueOf(birds[i][1]) + num);
	}

	static int calcBirdsSoldTotally() {
		int sum = 0;
		for (String[] i : birds) {
			sum += Integer.valueOf(i[3]);
		}
		return sum;
	}

	static String findBirdsLessThan3() {
		String result = "";

		for (String[] i : birds) {
			if (Integer.valueOf(i[1]) < 3) {
				result = result + i[0] + " ";
			}
		}

		return result;
	}

	static void sellBirds(String birdType, int num) {
		int i = getBirdIndex(birdType);
		if (num <= Integer.valueOf(birds[i][1])) {
			birds[i][1] = String.valueOf(Integer.valueOf(birds[i][1]) - num);
			birds[i][3] = String.valueOf(Integer.valueOf(birds[i][3]) + num);
		} else {
			System.out.println("Not enough birds of this type!");
		}
	}

	static void printBirdInfo(String birdType) {
		int i = getBirdIndex(birdType);
		if (i != -1) {
			System.out.println("Bird type: " + birds[i][0] + ", number: "
					+ birds[i][1] + ", price: $" + birds[i][2]
					+ ", birds sold: " + birds[i][3]);
		}
	}

	static void printBirdInfo() {
		if (birds == null || birds.length == 0) {
			System.out.println("There are no birds in array!");
		} else {
			System.out.println("*************************");
			for (String[] i : birds) {
				System.out.println("Bird type: " + i[0] + ", number: " + i[1]
						+ ", price: $" + i[2] + ", birds sold: " + i[3]);
			}
			System.out.println("*************************");
		}
	}

	static int calcProfit() {
		int sum = 0;
		for (String[] i : birds) {
			sum += Integer.valueOf(i[3]) * Integer.valueOf(i[2]);
		}
		return sum;
	}

	static int birdsTotal() {
		int sum = 0;
		for (String[] i : birds) {
			sum += Integer.valueOf(i[1]);
		}
		return sum;
	}

}