inheritance in java

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Inheritance is one of   the features of Object-Oriented Programming (OOPs). Inheritance allows a class to use the properties and methods of another class. In other words, the derived class inherits the states and behaviors from the base class. The derived class is also called subclass and the base class is also known as super-class. The derived class can add its own additional variables and methods. These additional variable and methods differentiates the derived class from the base class.
Inheritance is a compile-time mechanism. A super-class can have any number of subclasses. But a subclass can have only one superclass. This is because Java does not support multiple inheritances.
Types of Inheritance
*Multilevel Inheritance
*Multiple Inheritances
*Hybrid Inheritance
*Hierarchical Inheritance

Class Shape {
   private int length;
   private int breadth;
   public int getBreadth() {
      return breadth;
   }
   public int getLength() {
      return length;
   }
   public void setBreadth(int i) {
      breadth = i;
   }
   public void setLength(int i) {
      length = i;
   }
   // default Constructor
   Shape() {
      length = 0;
      breadth = 0;
      System.out.println("Inside default constructor of Shape ");
   }

   // Parameterized Constructor
   Shape(int len, int bdth) {
       length = len;
       breadth = bdth;
       System.out.println("Inside constructor of Shape ");
       System.out.println("length : " + length);
       System.out.println("breadth : " + breadth);
    }
}

// A subclass which extends for shape
class Rectangle extends Shape {
   private String type;

   // default Constructor
   Rectangle() {
      super();
      type = null;
      System.out.println("Inside default constructor of rectangle ");
   }

    // Parameterized Constructor
    Rectangle(String ty, int len, int bdth) {
       super (len, bdth);
       System.out.println("Inside constructor of rectangle ");
       System.out.println("length : " + len);
       System.out.println("breadth : " + bdth);
       System.out.println("type : " + type);
    }

    public String getType() {
       return type;
    }

    public void setType(String string) {
       type = string;
    }
}

// A subclass which extends for rectangle
class ColoredRectangle extends Rectangle {
    private String color;
    /* default Constructor*/
    ColoredRectangle() {
       super();
       color = null;
       System.out.println("Inside default constructor of coloredRectangle");
    }

     // Parameterized Constructor
     ColoredRectangle(String c, String ty, int len, int bdth) {
       super (ty, len, bdth);
       System.out.println("Inside constructor of coloredRectangle ");
       System.out.println("length : " + len);
       System.out.println("breadth : " + bdth);
       System.out.println("type : " + ty);
     }
     public String getColor() {
         return color;
     }
     public void setColor(String string) {
        color = string;
     }
}

public class Test {
   public static void main(String args[]) {
       ColoredRectangle CR = new ColoredRectangle();
       ColoredRectangle CR2 = new ColoredRectangle("Red","Big", 5, 2 );
   }
}


The output is:
Inside default constructor of Shape
Inside default constructor of rectangle
Inside default constructor of coloredRectangle
Inside constructor of Shape
Length: 5
Breadth: 2
Inside constructor of rectangle
Length: 5
Breadth: 2
Type: null
Inside constructor of coloredRectangle
Length: 5
Breadth: 2
Type: Big

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