Question

Java Programming II Homework 6

Create a class to represent a Farm object containing instances of the Animal objects

Farm

View javadoc for Animal and Farm classes https://bit.ly/2X6yxzw

- animals : Animal [ ] 
- farmName : String
- numAnimals : int         //calculated controlled variable no setter

+ Farm()                //default 10 animals 
+ Farm(String)            //default 10 animals 
+ Farm(int)            //size of array
+ Farm(String, int)    

+ addAnimal(Animal) : void    //use the next available slot to add the Animal, resize the array if necessary
+ getFarmName() : String
+ setFarmName(String) : void
+ getAnimal(int) : Animal             //return null if index is invalid
+ getNumAnimals() : int        //notice no setter… this is a controlled variable
+ getFirstAnimal() : Animal       
+ getLastAnimal() : Animal    
+ getAnimals() : Animal[ ]
+ printAllDetails() : void    // prints Farm attributes followed by Animal attributes as formatted below : 
                                // "FarmName: %20s | Number of Animals: %4d | Farm Size: %4d\n" 
                                // "Name: %20s | Year of Birth: %4d | Weight: %10.2f | Gender: %c\n"
+ removeAnimal(int) : Animal     
+ removeAllAnimals() : void
+ getTotalWeightOfAllAnimals() : double
+ getAverageWeightOfAllAnimals() : double
+ getNumberOfAnimalsAboveWeight(double) : int
+ getNumberOfAnimalsBelowWeight(double) : int
+ increaseWeightOfAllAnimals() : void
+ increaseWeightOfAllAnimals(double) : void

View javadoc for Animal and Farm classes https://bit.ly/2X6yxzw

Submission Instructions

'Main.java', 'Animal.java', and 'Farm.java'

Compile command: javac Main.java Animal.java Farm.java -Xlint:all -encoding utf-8

We will use this command to compile your code

Answer 1

Please feel free add more test code in Main.java

/Animal.java

package homeworks.hw3;

public class Animal {
   private String name;
   private int birthYear;
   private double weight;
   char gender;
   
   public Animal() {
   }
   
   public Animal(String name, int birthYear, double weight, char gender) {
      this.name = name;
      this.birthYear = birthYear;
      this.weight = weight;
      this.gender = gender;
   }
   
   public String getName() {
      return name;
   }
   
   public void setName(String name) {
      this.name = name;
   }
   
   public int getBirthYear() {
      return birthYear;
   }
   
   public void setBirthYear(int birthYear) {
      this.birthYear = birthYear;
   }
   
   public double getWeight() {
      return weight;
   }
   
   public void setWeight(double weight) {
      this.weight = weight;
   }
   
   public char getGender() {
      return gender;
   }
   
   public void setGender(char gender) {
      this.gender = gender;
   }
   
   public int calculateAge(int currentYear){
      if(currentYear<this.birthYear)return -1;
      return currentYear=birthYear;
   }
   public boolean isFemale(){
      return this.gender == 'F'|| this.gender == 'f';
   }
   public void gainWeight(){
      setWeight(getWeight()+1);
   }
   public void gainWeight(double weight){
      setWeight(getWeight()+weight);
   }
   public void loseWeight() {
      if(this.weight-1>=0){
         setWeight(getWeight()-1);
      }
   }
   public void loseWeight(double weight){
      if(this.weight-weight>=0){
         setWeight(getWeight()-weight);
      }
   }
   public void printDetails(){
      System.out.printf( "Name: %20s | Year of Birth: %4d | Weight: %10.2f | Gender: %c\n",
            this.name, this.birthYear, this.weight, this.gender);
   }
}

//Farm.java

package homeworks.hw3;

import java.util.Arrays;

public class Farm {
   private Animal[] animals;
   private String farmName;
   private int numAnimals;
   
   public Farm() {
      animals = new Animal[10];
      this.numAnimals = 0;
      this.farmName = "";
   }
   
   public Farm(int maxAnimals) {
      if (maxAnimals < 0) maxAnimals = 0;
      animals = new Animal[maxAnimals];
      this.numAnimals = 0;
      this.farmName = "";
   }
   
   public Farm(String farmName) {
      animals = new Animal[10];
      this.farmName = farmName;
      this.numAnimals = 0;
   }
   
   public Farm(String farmName, int maxAnimals) {
      if (maxAnimals < 0) maxAnimals = 0;
      this.farmName = farmName;
      this.numAnimals = 0;
      animals = new Animal[maxAnimals];
   }
   
   public String getFarmName() {
      return farmName;
   }
   
   public void setFarmName(String farmName) {
      this.farmName = farmName;
   }
   
   public void addAnimal(Animal a) {
      if (this.numAnimals >= animals.length) resizeAnimalArray();
      animals[numAnimals++] = a;
   }
   
   public Animal getAnimal(int index) {
      if (index < 0 || index >= numAnimals) return null;
      return animals[index];
   }
   
   public int getNumAnimals() {
      return this.numAnimals;
   }
   
   public Animal getFirstAnimal() {
      return animals[0];
   }
   
   public Animal getLastAnimal() {
      return animals[numAnimals-1];
   }
   
   public Animal[] getAnimals() {
      return this.animals;
   }
   
   public Animal removeAnimal(int index) {
      if(index<0 || index >= numAnimals) return null;
      Animal[] temp = new Animal[animals.length];
      int j=0;
      Animal a = animals[index];
      for(int i = 0; i<numAnimals; i++) {
         if(i != index)
         {
            temp[j] = animals[i];
            j++;
         }
      }
      temp[animals.length-1] = null;
      animals = temp;
      numAnimals -= 1;
      return a;
   }
   
   public void removeAllAnimals() {
      this.numAnimals = 0;
   }
   
   public double getTotalWeightOfAllAnimals() {
      double sum = 0;
      for(int i0=0;i0<numAnimals;i0++)
         sum += animals[i0].getWeight();
      return sum;
   }
   
   public double getAverageWeightOfAllAnimals() {
      return getTotalWeightOfAllAnimals() / (numAnimals);
   }
   
   public int getNumberOfAnimalsAboveWeight(double weight) {
      int i = 0;
      for(int i0=0;i0<numAnimals;i0++)
         if (animals[i0].getWeight() > weight)
            i++;
      return i;
   }
   
   public int getNumberOfAnimalsBelowWeight(double weight) {
      
      int i = 0;
      for(int i0=0;i0<numAnimals;i0++)
         if (animals[i0].getWeight() < weight)
            i++;
      return i;
   }
   
   public void increaseWeightOfAllAnimals() {
      for(int i=0;i<numAnimals;i++)
         animals[i].gainWeight();
   }
   
   public void increaseWeightOfAllAnimals(double weight) {
      for(int i0=0;i0<numAnimals;i0++)
         animals[i0].gainWeight(weight);
   }
   
   public void printAllDetails() {
      System.out.printf("FarmName: %20s | Number of Animals: %4d | Farm Size: %4d\n",
            this.farmName, this.numAnimals, animals.length);
      for(int i=0;i<numAnimals;i++)
         animals[i].printDetails();
   }
   
   public void resizeAnimalArray() {
      if (animals.length == 0) {
         animals = Arrays.copyOf(animals, 2);
      } else
         animals = Arrays.copyOf(animals, animals.length * 2);
   }
   
}

//Main.java

package homeworks.hw3;

public class Main {
   
   public static void main(String[] args) {
      Farm f = new Farm("MyFarm",-1);
      f.addAnimal(new Animal("a1",1978,34.6d,'M'));
      f.addAnimal(new Animal("a2",2013,33.6d,'F'));
      f.addAnimal(new Animal("a3",2001,31.6d,'M'));
      
      f.removeAnimal(1);
      
      f.printAllDetails();
   }

}

//OUTPUT

FarmName: MyFarm | Number of Animals: 2 | Farm Size: 4
Name: a1 | Year of Birth: 1978 | Weight: 34.60 | Gender: M
Name: a3 | Year of Birth: 2001 | Weight: 31.60 | Gender: M