added Oops concept and their program.

DataStructureAndAlgorithms/src/OOPs In Java/BMW.java

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+
+
+public class BMW extends car {
+
+	public String getCompany() {
+		return "BMW";
+	}
+}

DataStructureAndAlgorithms/src/OOPs In Java/car.java

@@ -0,0 +1,32 @@
+// inheritance : inherited form vehicle class
+
+
+
+public abstract class car extends vehicle{
+	int numGears;
+	boolean isConvertible;
+
+	public car() {
+		super(100);
+	}
+
+	public car(int numGears,int maxSpeed) {
+		super(maxSpeed);
+		this.numGears = numGears;
+		System.out.println("car");
+	}
+
+	public boolean isMoterized() {
+		return true;
+	}
+
+
+	public void print() {
+		//System.out.println("speed of car : " + maxSpeed);
+		super.print();
+		System.out.println("num of Gears in car : " + numGears);
+		System.out.println("car's convertible feature : " + isConvertible);
+
+	}
+
+}

DataStructureAndAlgorithms/src/OOPs In Java/car2.java

@@ -0,0 +1,13 @@
+
+
+public class car2 implements vehicle2 {
+	private int speed;
+
+	public int getSpeed() {
+		return speed;
+	}
+
+	public void setSpeed(int speed) {
+		this.speed = speed;
+	}
+}

DataStructureAndAlgorithms/src/OOPs In Java/carUse.java

@@ -0,0 +1,44 @@
+
+
+public class carUse {
+
+	public static void main(String[] args) {
+
+		vehicle v = new BMW();
+		v.color = "red";
+		//v.maxSpeed = 180;
+		v.setmaxSpeed(100);
+//		System.out.println(v.color);
+//		System.out.println(v.getmaxSpeed());
+//		v.print();
+
+
+		car c = new BMW();
+//		c.print();
+
+		c.color = "black";
+		//c.maxSpeed = 180;
+		c.setmaxSpeed(180);
+		c.numGears = 5;
+		c.isConvertible = true;
+
+		System.out.println(c.color);
+		//System.out.println(c.maxSpeed);
+		System.out.println(c.getmaxSpeed());
+		System.out.println(c.numGears);
+		System.out.println(c.isConvertible);
+		System.out.println(c.getCompany());
+
+		c.print();
+
+		vehicle v2 = new BMW();
+
+		v2.color = "red";
+		//v2.numGears; //error
+
+		vehicle2 v3 = new car2();
+		v3.setSpeed(9384757);
+		System.out.println(v3.getSpeed());
+	}
+
+}

DataStructureAndAlgorithms/src/OOPs In Java/fraction.java

@@ -0,0 +1,75 @@
+
+
+public class fraction {
+	private int numerator;
+    private	int denominator;
+
+    public fraction(int numerator, int denominator) {
+    	this.numerator = numerator; 
+//    	if(denominator == 0 )
+//    		// error out 
+    	this.denominator  = denominator;
+
+    	simplify();
+    }
+
+    public void setNumerator(int numerator){
+    	this.numerator = numerator;
+    	simplify();
+    }
+
+    public void setDenominator(int denominator) {
+//    	if(denominator == 0)
+//    		// error out 
+    	this.denominator = denominator;
+    	simplify();
+    }
+
+    public int getNumerator() {
+    	return numerator;
+    }
+
+    public int getDenominator() {
+    	return denominator;
+    }
+
+    private void simplify() {
+    	int gcd = 1;
+
+    	int smaller = Math.min(numerator, denominator);
+    	for(int i=2; i<=smaller; i++) {
+    		if((numerator%i == 0) && (denominator%i == 0))
+   			 gcd = i;
+    	}
+    	numerator = numerator/gcd;
+    	denominator = denominator/gcd ;
+    }
+
+    public void print() {
+    	simplify();
+    	if(denominator == 1)
+    		 System.out.println(numerator);
+    	else
+    		System.out.println(numerator + "/" + denominator);
+    }
+
+    public void add(fraction f) {
+    	this.numerator = this.numerator*f.denominator + this.denominator*f.numerator;
+    	this.denominator = this.denominator*f.denominator;
+    	simplify();
+    }
+
+    public void multiply(fraction f) {
+    	this.numerator *= f.numerator;
+    	this.denominator *= f.denominator;
+    	simplify();
+    }
+
+    public static fraction add(fraction f1, fraction f2) {
+    	int a = f1.numerator*f2.denominator + f1.denominator*f2.numerator;
+    	int b = f1.denominator*f2.denominator;
+    	fraction f = new fraction(a,b);
+    	return f;
+    }
+
+}

DataStructureAndAlgorithms/src/OOPs In Java/fractionUse.java

@@ -0,0 +1,34 @@
+
+
+
+public class fractionUse {
+
+	public static void main(String[] args) {
+		fraction f1 = new fraction(50, 40);
+		fraction f2 = new fraction(30, 20);
+		fraction f3 = new fraction(8, 6);
+		f1.print();
+		f2.print();
+		f3.print();
+
+		System.out.println(f1.getNumerator());
+		System.out.println(f1.getDenominator());
+
+		f2.setNumerator(1);
+		f2.setDenominator(2);
+		f2.print();
+
+		f1.add(f2);
+
+		f1.print();
+
+		f2.multiply(f3);
+		f2.print();
+
+		f3 = fraction.add(f1,f2);
+
+		f3.print();
+
+	}
+
+}

DataStructureAndAlgorithms/src/OOPs In Java/student.java

@@ -0,0 +1,33 @@
+
+
+public class student {
+	public String name;
+	public int rollNo;
+	private int age;
+	private static int numStudent;    // static member is same for all objects;
+
+	public student() {        // default constructor
+		numStudent++;
+	}
+	public student(String name, int rollNo, int age) {
+		this.name = name;
+		this.rollNo = rollNo;
+		this.age = age;
+		numStudent++;
+	}
+
+	public void setAge(int age) {
+		if(age<16)             // this is the actual use of set function
+			return;            //that control of setting data is in your hand     
+
+		this.age = age;
+	}
+
+	public int getAge() {
+		return this.age;
+	}
+
+	public static int getNumStudent() {
+		return numStudent;
+	}
+}

DataStructureAndAlgorithms/src/OOPs In Java/studentUse.java

@@ -0,0 +1,47 @@
+
+
+public class studentUse {
+
+	public static void main(String[] args) {
+		student s1 = new student();
+		student s2 = new student();
+
+
+		s1.name = "Ajay";
+		s1.rollNo = 15;
+		//s1.age = 23;   note allowed
+		s1.setAge(12);   // returns 0;
+ 		s1.setAge(23);
+
+
+		s2.name = "sachin";
+		s2.rollNo = 131;
+		 // s2.age = 21;   not allowed
+		s2.setAge(21);
+
+		System.out.println(s1.name);
+		System.out.println(s1.rollNo);
+		//System.out.println(s1.age);    // not allowed
+		System.out.println(s1.getAge());
+
+		System.out.println(s2.name);
+		System.out.println(s2.rollNo);
+		//System.out.println(s2.age);   // not allowed
+		System.out.println(s2.getAge());
+
+
+
+		// constructor use
+
+		student s3 = new student("nayan", 190,21);
+
+		System.out.println(s3.name);
+		System.out.println(s3.rollNo);
+		System.out.println(s3.getAge());
+
+		System.out.println(s1.getNumStudent() + " " + s2.getNumStudent() + " " + s3.getNumStudent() + " " + student.getNumStudent());    // all have same value;
+
+
+	}
+
+}

DataStructureAndAlgorithms/src/OOPs In Java/vehicle.java

@@ -0,0 +1,28 @@
+
+
+public abstract class vehicle {
+	protected String color;
+	private int maxSpeed;
+
+	public vehicle(int maxSpeed) {
+		this.maxSpeed = maxSpeed;
+		System.out.println("vehicle");
+	}
+
+
+	public int getmaxSpeed() {
+		return maxSpeed;
+	}
+	public void setmaxSpeed(int maxSpeed) {
+		this.maxSpeed = maxSpeed;
+	}
+
+	public abstract String getCompany();
+
+	public abstract boolean isMoterized();
+
+	public void print() {
+		System.out.println("color of vehicle : " + color);
+		System.out.println("speed of vehicle : " + maxSpeed);		
+	}
+}

DataStructureAndAlgorithms/src/OOPs In Java/vehicle2.java

@@ -0,0 +1,6 @@
+
+
+public interface vehicle2 {
+	public int getSpeed();
+	public void setSpeed(int speed);
+}