2012-2013 учебный год
Презентация к семинару
Семинар 1. IDE Eclipse
Пример 1. Светофор. Реализация интерфейса в Java
Файл TrafficRegulator.java
interface Lights{ int RED = 0; int YELLOW = 1; int GREEN = 2; int ERROR = -1; } class Timer implements Lights{ private int delay; private static int light = RED; Timer(int sec){delay = 1000 * sec;} public int shift(){ int count = (light++) % 3; try{ switch(count){ case RED: Thread.sleep(delay); break; case YELLOW: Thread.sleep(delay/3); break; case GREEN: Thread.sleep(delay/2); break; } }catch(Exception e){return ERROR;} return count; } } class TrafficRegulator{ private static Timer t = new Timer(1); public static void main(String[] args){ for (int k = -0; k < 10; k++) switch(t.shift()){ case Lights.RED: System.out.println("Stop!"); break; case Lights.YELLOW: System.out.println("Wait!"); break; case Lights.GREEN: System.out.println("Go!"); break; case Lights.ERROR: System.err.println("Time Error"); break; default: System.err.println("Unknown light."); return; } } }
Установка IDE Eclipse