Those years, learn together Java 5-1 5-2

/**5-1

* Define interface printable, which includes a method Printitmyway (),

* This method has no formal parameters and the return value is null

**/

Interface Printable{void Printitmyway ();}

/**5-2

* Rewrite the rectangle class in experiment 3 to implement the printable interface,

* Use the Printitmyway () method to relate information about the rectangle (length, width, perimeter, area)

* Print on the screen;

* Rewrite the square class in experiment 4, overloading the Printitmyway () method

* Print information about the square (edge length, perimeter, area) on the screen

**/

public class firstprogram{public static void main  (String[] args) {Rectangle  rectangle = new rectangle (12, 21); Square square = new square (4); Rectangle.printitmyway (); Square.printitmyway ();}} Interface printable{void printitmyway ();}  class rectangle implements printable{protected int length;protected int  width; rectangle  () {}rectangle (int l, int w) {this.length = l;this.width = w;} Void show () {System.out.println (" length: "  + length +  " width: "  + width);} int perimeter  () {return  (Length + width)  * 2;} int area  () {return length * width;}     public void printitmyway () {this.show (); System.out.println (" permiter: "  + this.perimeter ()  +  " area: " &nbsP;+ this.area ());}}  class Square  extends Rectangle{protected int side; square  (int side) {super (); this.side = side;} Void show () {System.out.println (" side: "  + side);} int perimeter  () {return 4 * side;} int area  () {return side * side;}}

Those years, learn together Java 5-1 5-2