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1. ¼òµ¥¹¤³§:
(1). ´´½¨Êä³ö(Output)½Ó¿Ú
package stone;
public interface Output {
    public int MAX_COUNT =10;               // ×î¶à¿É´òÓ¡¶àÉÙÌõ¼Ç¼
    public void show();                            // ´òÓ¡
    public void addData(String msg);      // °ÑÒª´òÓ¡µÄ¼Ç¼¼ÓÈëµ½´òÓ¡ÅÅÐò
}
(2). ´´½¨´òÓ¡»úÀà, Æä¼Ì³ÐÊä³ö½Ó¿Ú
package stone;
public class Printer implements Output {
    private String[] data_array= new String[MAX_COUNT];      // ±£´æÒª´òÓ¡ÐÅÏ¢µÄÊý×é
    private int dataNum=0;                                                       //  Òª´òÓ¡ÐÅÏ¢µÄ¸öÊý
    public void addData(String msg) {
        if(dataNum>MAX_COUNT)                                               // Òª´òÓ¡µÄÐÅÏ¢²»ÄÜ´óÊ¿×î´óÖµ
            System.out.println("Print queue is max");
        else
            data_array[dataNum++]=msg;
    }
    public void show() {
        while(dataNum>0){