简单工厂
/** * Description: * <br/>Copyright (C), 2001-2010, Yeeku.H.Lee * <br/>This program is protected by copyright laws. * <br/>Program Name: * <br/>Date: * @author Yeeku.H.Lee kongyeeku@163.com * @version 1.0 */public class Computer{private Output out;public Computer(Output out){this.out = out;}//定义一个模拟获取字符串输入的方法public void keyIn(String msg){out.getData(msg);}//定义一个模拟打印的方法public void print(){out.out();}public static void main(String[] args) {//创建OutputFactoryOutputFactory of = new OutputFactory();//将Output对象传入，创建Computer对象Computer c = new Computer(of.getOutput());c.keyIn("轻量级J2EE企业应用实战");c.keyIn("Struts2权威指南");c.print();}}/** * Description: * <br/>Copyright (C), 2001-2010, Yeeku.H.Lee * <br/>This program is protected by copyright laws. * <br/>Program Name: * <br/>Date: * @author Yeeku.H.Lee kongyeeku@163.com * @version 1.0 */public interface Output{//接口里定义的属性只能是常量int MAX_CACHE_LINE = 50;//接口里定义的只能是public的抽象实例方法void out();void getData(String msg);}/** * Description: * <br/>Copyright (C), 2001-2010, Yeeku.H.Lee * <br/>This program is protected by copyright laws. * <br/>Program Name: * <br/>Date: * @author Yeeku.H.Lee kongyeeku@163.com * @version 1.0 */public class OutputFactory{public Output getOutput(){//下面两行代码用于控制系统到底使用Output的哪个实现类。//return new Printer();return new BetterPrinter();}}/** * Description: * <br/>Copyright (C), 2001-2010, Yeeku.H.Lee * <br/>This program is protected by copyright laws. * <br/>Program Name: * <br/>Date: * @author Yeeku.H.Lee kongyeeku@163.com * @version 1.0 *///让Printer类实现Outputpublic class Printer implements Output{private String[] printData = new String[MAX_CACHE_LINE];//用以记录当前需打印的作业数private int dataNum = 0;public void out(){//只要还有作业，继续打印while(dataNum > 0){System.out.println("打印机打印：" + printData[0]);//把作业队列整体前移一位，并将剩下的作业数减1System.arraycopy(printData , 1, printData, 0, --dataNum);}}public void getData(String msg){if (dataNum >= MAX_CACHE_LINE){System.out.println("输出队列已满，添加失败");}else{//把打印数据添加到队列里，已保存数据的数量加1。printData[dataNum++] = msg;}}}/** * Description: * <br/>Copyright (C), 2001-2010, Yeeku.H.Lee * <br/>This program is protected by copyright laws. * <br/>Program Name: * <br/>Date: * @author Yeeku.H.Lee kongyeeku@163.com * @version 1.0 */public class BetterPrinter implements Output{private String[] printData = new String[MAX_CACHE_LINE * 2];//用以记录当前需打印的作业数private int dataNum = 0;public void out(){//只要还有作业，继续打印while(dataNum > 0){System.out.println("高速打印机正在打印：" + printData[0]);//把作业队列整体前移一位，并将剩下的作业数减1System.arraycopy(printData , 1, printData, 0, --dataNum);}}public void getData(String msg){if (dataNum >= MAX_CACHE_LINE * 2){System.out.println("输出队列已满，添加失败");}else{//把打印数据添加到队列里，已保存数据的数量加1。printData[dataNum++] = msg;}}}