Java examples for Object Oriented Design:interface
Create an Interface and then implement the interface
import java.awt.Point; class RectanglePlus implements Relatable { public int width = 0; public int height = 0; public Point origin; // four constructors public RectanglePlus() { origin = new Point(0, 0); }/*from ww w .java 2s . c om*/ public RectanglePlus(Point p) { origin = p; } public RectanglePlus(int w, int h) { origin = new Point(0, 0); width = w; height = h; } public RectanglePlus(Point p, int w, int h) { origin = p; width = w; height = h; } // a method for moving the rectangle public void move(int x, int y) { origin.x = x; origin.y = y; } // a method for computing the area of the rectangle public int getArea() { return width * height; } // a method to implement Relatable public int isLargerThan(Relatable other) { RectanglePlus otherRect = (RectanglePlus) other; if (this.getArea() < otherRect.getArea()) return -1; else if (this.getArea() > otherRect.getArea()) return 1; else return 0; } } interface Relatable { // this (object calling isLargerThan) and // other must be instances of the same class // returns 1, 0, -1 if this is greater // than, equal to, or less than other public int isLargerThan(Relatable other); } /* * Copyright (c) 1995, 2008, Oracle and/or its affiliates. All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * * - Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * * - Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * * - Neither the name of Oracle or the names of its * contributors may be used to endorse or promote products derived * from this software without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS * IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. */