Coding exercises--java-5-interface, inheritance and polymorphism __ajax

Welcome to visit the blog Basic Definition interface

Public interface Icalculate {
    final float pi=3.14159f;
    Float Getarea (float R);
    Float getcircumference (float R);
}

Implementing interfaces
Note: All methods (abstractions) to implement the interface

The public class Cire implements Icalculate {
    //the Circle area is public
    float Getarea (float r) {
        float = pi*r*r;
        return area;
    }
    Computes the circumference of the circle public
    float getcircumference (float r) {
        float circumference = 2*pi*r;
        return circumference
    }
}

Instances-save pictures in different formats
Defining interfaces

Public interface Imagesaver {
    void Save ();
}

Implementing interfaces

public class Gifsaver implements Imagesaver {
    //rewrite-polymorphic
    @Override public
    Void Save () {
        System.out.println (save picture in GIF format);
    }

Example-to increase the GPS positioning function for automobiles
Parent class

public class Car {
    private String name;
    private double speed;
    Omit Getxx () and SETXX () public
    double GetSpeed () {return
        speed;
    }
    @Override public
    String toString () {
        StringBuilder sb = new StringBuilder ();
        Sb.append ("Car name:" + name + ",");
        Sb.append ("Speed:" + speed + "kilometer/hour");
        return sb.tostring ();
    }

Defining interfaces

Import Java.awt.Point;
Public interface GPS {public point
    getLocation ();
}

Implementing interfaces

Import Java.awt.Point;
public class Gpscar extends car implements GPS {
    @Override public point
    getLocation () {point point
        = new Poin T ();
        Point.setlocation (Super.getspeed (), Super.getspeed ());
        return point;
    }

    @Override public 
    String toString () {
        StringBuilder sb = new StringBuilder ();
        Sb.append (Super.tostring ());
        Sb.append (", Coordinates: (" + getLocation (). x + "," + getLocation (). Y + ")");
        return sb.tostring ();
    }

Test class

Import Java.awt.Point;
public class Test {public
    static void Main (string[] args) {
        Gpscar gcar = new Gpscar ();
        Point point = Gcar.getlocation ();
        System.out.println ("Coordinates: (" + Point.x + "," + Point.y +) ");
        String info = gcar.tostring ();
        SYSTEM.OUT.PRINTLN (info);
    }

Inherited

public class Test {public
    static void Main (string[] args) {
        pigeon pigeon = new pigeon ();
        System.out.println (Pigeon.color);
    }

The parent class class
Bird {
    String color = "white";
    String skin = "feather";
}
Subclass-Inheritance (properties and methods)
class Pigeon extends Bird {
}

Inheritance-overriding

public class Test {public
    static void Main (string[] args) {
        Dog Dog = new Dog ();
        SYSTEM.OUT.PRINTLN ("The output of the execution dog.cry (); statement:");
        Dog.cry ();
        Cat cat = new Cat ();
        SYSTEM.OUT.PRINTLN ("The output of the execution cat.cry (); statement:");
        Cat.cry ();
        Sheep Sheep = new Sheep ();
        SYSTEM.OUT.PRINTLN ("The output of the execution cat.cry (); statement:");
        Sheep.cry ();
    }

The parent class
class Animal {public
    Animal () {} is public

    void Cry () {System.out.println ()
        The animal makes a call. ");
    }
}
Subclass Class
Dog extends Animal {public
    Dog () {

    } public

    void Cry () {
        System.out.println ("Dog issue" Bark ... "sound. ");
    }
}
Subclass Class
Cat extends Animal {public
    cat () {

    } public

    void Cry () {
        System.out.println ("Cat emit" Meow meow ... "sound. ");
    }
}
Subclass Class
Sheep extends Animal {

}

Calling constructors, member variables, and member methods of the parent class

public class Test {public
    static void Main (string[] args) {
        Tiger Tiger = new Tiger ();
        System.out.println ("Tiger skin:" + tiger.skin);
        Tiger.test ();
    }

The parent class
class Beast {
    String skin = "";
    Public Beast () {    //parameterless constructor} public
    Beast (String strskin) {
        skin = Strskin;
    }
    public void Move () {
        System.out.println ("Run");
    }
Subclass-Inheritance (properties and methods)
class Tiger extends Beast {public
    tiger () {
        super ("stripe");    Construct method with parameters with parent class
    } public
    void Test () {
        System.out.println ("Skin of Parent: + Super.skin");
        System.out.println ("The action of the parent class runs:");
        Super.move ();
    }

Instances-Differences between managers (subclasses) and employees (parent classes)

Import Java.util.Date;
        public class Test {public static void main (string[] args) {Employee employee = new Employee ();
        Employee.setname ("Java");
        Employee.setsalary (100);
        Employee.setbirthday (New Date ());
        Manager Manager = new manager ();
        Manager.setname ("Tomorrow Technology");
        Manager.setsalary (3000);
        Manager.setbirthday (New Date ());
        Manager.setbonus (2000);
        Output Manager and Employee Attribute values System.out.println ("Employee's name:" + employee.getname ());
        SYSTEM.OUT.PRINTLN ("Employee's Salary:" + employee.getsalary ());
        SYSTEM.OUT.PRINTLN ("Employee's Birthday:" + employee.getbirthday ());
        System.out.println ("Manager's name:" + manager.getname ());
        System.out.println ("Manager's Salary:" + manager.getsalary ());
        System.out.println ("Manager's Birthday:" + manager.getbirthday ());
    System.out.println ("Manager's Bonus:" + Manager.getbonus ());
    }///Parent class class Employee {private String name;
    private double salary;
    Private Date birthday; Public String GetnamE () {return name;
    public void SetName (String name) {this.name = name;
    Public double getsalary () {return salary;
    The public void Setsalary (double salary) {this.salary = salary;
    Public Date Getbirthday () {return birthday;
    The public void Setbirthday (Date birthday) {this.birthday = birthday;
    }//Subclass-Inheritance (Properties and methods) class Manager extends Employee {private double bonus;
    Public double Getbonus () {return bonus;
    The public void Setbonus (double bonus) {This.bonus = bonus; }
}

Instance-overriding methods in the parent class

public class Test {public
    static void Main (string[] args) {
        Employee employee = new Employee ();
        System.out.println (Employee.getinfo ());
        Manager Manager = new manager ();
        System.out.println (Manager.getinfo ());
    }

Parent class
Employee {public
    String GetInfo () {return
        "parent": I'm an employee of tomorrow's technology. ";
    }
}
Subclass-Override
class Manager extends Employee {
    @Override public
    String GetInfo () {return
        "subclass: I'm the manager of tomorrow's technology. ";
    }
}

Polymorphic

public class Test {
    final float pi=3.14159f;
    To find the area of the circle public
    float Getarea (float r) {
        float = pi*r*r;
        return area;
    }
    To find the area of the rectangle public
    float Getarea (float l, float W) {
        float areas = l*w;
        return area;
    }
    Draw a graphic of any shape public
    void draw (int num) {
        System.out.println ("draw" + num + "freeform shape");
    }
    Draws the specified shape's graphics public
    void Draw (String shape) {
        System.out.println ("Draw one" + shape);
    }

    public static void Main (string[] args) {
        test test = new test ();
        float l=20;
        float w=30;
        float Arearectangle = Test.getarea (l, W);
        System.out.println ("+l+" width to "+w+" the area of the rectangle is: "+ arearectangle);
        float r = 7;
        float Areacirc = Test.getarea (r);
        System.out.println ("The radius is" +r+ "the area of the circle is:" +areacirc);
        int num=7;
        Test.draw (num);
        Test.draw ("triangle");
    }

Instance-Calculates the area of the geometry

public class Test {public static void main (string[] args) {Circle Circle = new Circle (1);
        System.out.println ("Graphic name is:" + circle.getname ());

        System.out.println ("The area of the graph is:" + Circle.getarea ());
        Rectangle Rectangle = new Rectangle (1, 1);
        System.out.println ("Graphic name is:" + rectangle.getname ());
    System.out.println ("The area of the graph is:" + Rectangle.getarea ());
    }///Parent abstract class Shape {public String getName () {return This.getclass (). Getsimplename ();//Get the name of the graphic   public abstract double Getarea ();
    Get the area of the graphic}//Subclass class Circle extends shape {private double radius;
    Public Circle (double radius) {This.radius = radius;
    @Override public Double Getarea () {return Math.pi*math.pow (RADIUS, 2);
    }//Subclass class Rectangle extends Shape {private double length;
    private double width;
        Public Rectangle (double length, double width) {this.length = length; This.width =Width
    @Override public Double Getarea () {return length * width; }
}

Example-Simple car Sales Mall

public class Test {public
    static void Main (string[] args) {
        System.out.println ("customer wants to buy BMW:");
        Car BMW = Carfactory.getcar ("BMW");
        System.out.println ("Extraction car:" + bmw.getinfo ());

        System.out.println ("Customers want to buy Benz:");
        Car Benz = Carfactory.getcar ("Benz");
        System.out.println ("Extraction car:" + benz.getinfo ());
    }

Parent abstract class Car
{public
    abstract String getInfo ();
}
Subclass class
BMW extends car {
    @Override public
    String GetInfo () {return
        "BMW";
    }
}
Subclass class
Benz extends car {
    @Override public
    String GetInfo () {return
        "Benz";
    }
}
Factory
class Carfactory {public
    static car Getcar (String name) {
        if (name.equalsignorecase ("BMW")) { Return to
            new BMW ();
        } else if (name.equalsignorecase ("Benz")) {return
            new Benz ():
        } else {return
            null;
        }
}}

Instance-custom sort using the comparable interface

public class Employee implements comparable<employee> {private int id;
    private String name;
    private int age;
        public Employee (int ID, String name, int age) {//constructor this.id = ID;
        THIS.name = name;
    This.age = age;
        @Override public int compareTo (Employee o) {if (id > O.id) {return 1;
        else if (ID < o.id) {return-1;
    return 0;
        @Override public String toString () {StringBuilder sb = new StringBuilder ();
        Sb.append ("Employee's number:" + ID + ",");
        Sb.append ("Employee's name:" + name + ",");
        Sb.append ("Age of the Employee:" + aged);
    return sb.tostring ();
        public static void Main (string[] args) {Employee employee1 = new Employee (1000, "Learning Annals", 27);
        Employee Employee2 = new Employee (1001, "Sunny", 27);
        System.out.println ("Comparison result:" + Employee1.compareto (employee2));
 SYSTEM.OUT.PRINTLN ("Employee Information:" + employee1.tostring ());   }
}