TR-Java-lecture07-interface(接口)课件.ppt

Java程序设计;Contents;Single vs. Multiple Inheritance;Abstract Classes（抽象类）;Abstract Classes（抽象类）;Abstract Classes;Abstract Classes;Abstract Class -Example;The Shape Abstract Class;The Shape Abstract Class;Abstract Classes Properties;Interface(接口);例：;Interface;Interfaces;Interfaces;Defining Interface;Interface - Example;class Lecturer implements Speaker { public void speak(){ System.out.println(“Talks Object Oriented Design and Programming!”); } };Interface Inheritance;Interface Inheritance — Example 1;class InterfaceInheritance { public static void main(String args[]) { I i = new I(); System.out.println(i.j); System.out.println(i.j1()); System.out.println(i.k1()); System.out.println(i.l1()); } };Interface Inheritance — Example 2;interface I1{ int nValue = 1; void amethod(); } interface I2 { int nValue = 2; void amethod(); };Interface Inheritance — Example 2; class Z implements Total { } class AmbiguousVariable { public static void main(String args[]) { Z z = new Z(); System.out.println(z.base); System.out.println(z.set1); System.out.println(z.set2); System.out.println(z.total); System.out.println(z.ambiguous);//非法，Compile Error } };Inheritance and Interface Implementation;Example;class Circle extends Shape implements 2DShape { double radius; String color; public Circle(double r) { redius = r; } public void setColor(String str) { color = str; System.out.println(“color is “+color); } public double area() { return (pi*radius*radius); } };