{"id":1131,"date":"2023-03-16T21:50:36","date_gmt":"2023-03-16T13:50:36","guid":{"rendered":"https:\/\/www.appblog.cn\/?p=1131"},"modified":"2023-04-29T10:01:27","modified_gmt":"2023-04-29T02:01:27","slug":"design-pattern-flyweight-pattern","status":"publish","type":"post","link":"https:\/\/www.appblog.cn\/index.php\/2023\/03\/16\/design-pattern-flyweight-pattern\/","title":{"rendered":"\u8bbe\u8ba1\u6a21\u5f0f\uff0822\uff09\u4eab\u5143\u6a21\u5f0f"},"content":{"rendered":"

\u4eab\u5143\u6a21\u5f0f\u662f\u7ed3\u6784\u578b\u8bbe\u8ba1\u6a21\u5f0f\u4e4b\u4e00\uff0c\u662f\u5bf9\u5bf9\u8c61\u6c60\u7684\u4e00\u79cd\u5b9e\u73b0\u3002\u5c31\u50cf\u5b83\u7684\u540d\u5b57\u4e00\u6837\uff0c\u5171\u4eab\u5bf9\u8c61\uff0c\u907f\u514d\u91cd\u590d\u7684\u521b\u5efa\u3002\u6211\u4eec\u5e38\u7528\u7684String \u5c31\u662f\u4f7f\u7528\u4e86\u5171\u4eab\u6a21\u5f0f\uff0c\u6240\u4ee5String\u7c7b\u578b\u7684\u5bf9\u8c61\u521b\u5efa\u540e\u5c31\u4e0d\u53ef\u6539\u53d8\uff0c\u5982\u679c\u5f53\u4e24\u4e2aString\u5bf9\u8c61\u6240\u5305\u542b\u7684\u5185\u5bb9\u76f8\u540c\u65f6\uff0cJVM\u53ea\u521b\u5efa\u4e00\u4e2aString\u5bf9\u8c61\u5bf9\u5e94\u8fd9\u4e24\u4e2a\u4e0d\u540c\u7684\u5bf9\u8c61\u5f15\u7528\u3002<\/p>\n

<\/p>\n

\u5b9a\u4e49<\/h2>\n

\u91c7\u7528\u4e00\u4e2a\u5171\u4eab\u6765\u907f\u514d\u5927\u91cf\u62e5\u6709\u76f8\u540c\u5185\u5bb9\u5bf9\u8c61\u7684\u5f00\u9500\u3002\u4f7f\u7528\u4eab\u5143\u6a21\u5f0f\u53ef\u6709\u6548\u652f\u6301\u5927\u91cf\u7684\u7ec6\u7c92\u5ea6\u5bf9\u8c61\u3002<\/p>\n

\u4f7f\u7528\u573a\u666f<\/h2>\n

\uff081\uff09\u7cfb\u7edf\u4e2d\u5b58\u5728\u5927\u91cf\u7684\u76f8\u4f3c\u5bf9\u8c61\u3002
\n\uff082\uff09\u7ec6\u7c92\u5ea6\u7684\u5bf9\u8c61\u90fd\u5177\u5907\u8f83\u63a5\u8fd1\u7684\u5916\u90e8\u72b6\u6001\uff0c\u800c\u4e14\u5185\u90e8\u72b6\u6001\u4e0e\u73af\u5883\u4e0d\u5173\uff0c\u4e5f\u5c31\u662f\u8bf4\u5bf9\u8c61\u6ca1\u6709\u7279\u5b9a\u8eab\u4efd\u3002
\n\uff083\uff09\u9700\u8981\u7f13\u51b2\u6c60\u7684\u573a\u666f\u3002<\/p>\n

PS\uff1a\u5185\u90e8\u72b6\u6001\u4e0e\u5916\u90e8\u72b6\u6001\uff1a\u5728\u4eab\u5143\u5bf9\u8c61\u5185\u90e8\u5e76\u4e14\u4e0d\u4f1a\u968f\u7740\u73af\u5883\u6539\u53d8\u800c\u6539\u53d8\u7684\u5171\u4eab\u90e8\u5206\uff0c\u53ef\u4ee5\u79f0\u4e4b\u4e3a\u4eab\u5143\u5bf9\u8c61\u7684\u5185\u90e8\u72b6\u6001\uff0c\u53cd\u4e4b\u968f\u7740\u73af\u5883\u6539\u53d8\u800c\u6539\u53d8\u7684\uff0c\u4e0d\u53ef\u5171\u4eab\u7684\u72b6\u6001\u79f0\u4e4b\u4e3a\u5916\u90e8\u72b6\u6001\u3002<\/p>\n

UML\u7c7b\u56fe<\/h2>\n

\u4eab\u5143\u6a21\u5f0f\u5206\u4e3a\u5355\u7eaf\u4eab\u5143\u6a21\u5f0f\u548c\u590d\u5408\u4eab\u5143\u6a21\u5f0f<\/p>\n

\uff081\uff09Flyweight<\/code>\uff1a\u4eab\u5143\u5bf9\u8c61\u62bd\u8c61\u57fa\u7c7b\u6216\u8005\u63a5\u53e3\u3002
\n\uff082\uff09ConcreateFlyweight<\/code>\uff1a\u5177\u4f53\u7684\u4eab\u5143\u5bf9\u8c61\uff0c\u5982\u679c\u6709\u5185\u90e8\u72b6\u6001\u7684\u8bdd\uff0c\u5fc5\u987b\u8d1f\u8d23\u4e3a\u5185\u90e8\u72b6\u6001\u63d0\u4f9b\u5b58\u50a8\u7a7a\u95f4\u3002
\n\uff083\uff09UnsharadConcreateFlyweight<\/code>\uff1a\u590d\u5408\u4eab\u5143\u89d2\u8272\u6240\u4ee3\u8868\u7684\u5bf9\u8c61\u662f\u4e0d\u53ef\u4ee5\u5171\u4eab\u7684\uff0c\u5e76\u4e14\u53ef\u4ee5\u5206\u89e3\u6210\u4e3a\u591a\u4e2a\u5355\u7eaf\u4eab\u5143\u5bf9\u8c61\u7684\u7ec4\u5408\u3002\u5355\u7eaf\u4eab\u5143\u6a21\u5f0f\u6ca1\u6709\u6b64\u9879\uff0c\u8fd9\u4e5f\u662f\u4e24\u8005\u5728\u7ed3\u6784\u4e0a\u7684\u533a\u522b\u3002
\n\uff084\uff09FlyweightFactoiy<\/code>\uff1a\u4eab\u5143\u5de5\u5382\uff0c\u8d1f\u8d23\u7ba1\u7406\u4eab\u5143\u5bf9\u8c61\u6c60\u548c\u521b\u5efa\u4eab\u5143\u5bf9\u8c61\u3002
\n\uff085\uff09Client<\/code>\uff1a\u7ef4\u62a4\u5bf9\u6240\u6709\u4eab\u5143\u5bf9\u8c61\u7684\u5f15\u7528\uff0c\u800c\u4e14\u8fd8\u9700\u8981\u5b58\u50a8\u5bf9\u5e94\u7684\u5916\u8574\u72b6\u6001\u3002<\/p>\n

\u7b80\u5355\u5b9e\u73b0<\/h2>\n

\u60c5\u666f\uff1a\u8fc7\u5e74\u4e70\u706b\u8f66\u7968\u7684\u65f6\u5019\uff0c\u6211\u4eec\u9700\u8981\u67e5\u8be2\u8f66\u7968\u7684\u60c5\u51b5\uff0c\u90a3\u4e48\u5982\u679c\u6bcf\u6b21\u67e5\u8be2\u8f66\u7968\u65f6\u90fd\u521b\u5efa\u4e00\u4e2a\u7ed3\u679c\uff0c\u90a3\u4e48\u5fc5\u7136\u4f1a\u5927\u91cf\u7684\u521b\u5efa\u51fa\u8bb8\u591a\u91cd\u590d\u7684\u5bf9\u8c61\uff0c\u9891\u7e41\u7684\u53bb\u9500\u6bc1\u4ed6\u4eec\uff0c\u4f7f\u5f97GC\u4efb\u52a1\u7e41\u91cd\u3002\u90a3\u4e48\u8fd9\u65f6\u6211\u4eec\u53ef\u4ee5\u4f7f\u7528\u4eab\u5143\u6a21\u5f0f\uff0c\u5c06\u8fd9\u4e9b\u5bf9\u8c61\u7f13\u5b58\u8d77\u6765\uff0c\u67e5\u8be2\u65f6\u4f18\u5148\u4f7f\u7528\u7f13\u5b58\uff0c\u6ca1\u6709\u7f13\u5b58\u5728\u91cd\u65b0\u521b\u5efa\u3002<\/p>\n

\u9996\u5148\u662fTicket\u63a5\u53e3\uff08Flyweight\uff09\uff1a<\/p>\n

public interface Ticket {\n\n    public void showTicketInfo(String bunk);\n\n}<\/code><\/pre>\n
TrainTicket\u5177\u4f53\u5b9e\u73b0\u7c7b\uff08ConcreateFlyweight\uff09\uff1a<\/p>\n
\/\/\u706b\u8f66\u7968\npublic class TrainTicket implements Ticket{\n\n    public String from; \/\/ \u59cb\u53d1\u5730\n    public String to; \/\/ \u76ee\u7684\u5730\n    public String bunk; \/\/\u94fa\u4f4d\n    public int price; \/\/\u4ef7\u683c\n\n    public TrainTicket(String from, String to) {\n        this.from = from;\n        this.to = to;\n    }\n\n    @Override\n    public void showTicketInfo(String bunk) {\n        price = new Random().nextInt(300);\n        System.out.println("\u8d2d\u4e70 \u4ece " + from + " \u5230 " + to + "\u7684" + bunk + "\u706b\u8f66\u7968" + ", \u4ef7\u683c\uff1a" + price);\n    }\n\n}<\/code><\/pre>\n
TicketFactory \u7ba1\u7406\u67e5\u8be2\u706b\u8f66\u7968\uff08FlyweightFactoiy\uff09:<\/p>\n
public class TicketFactory {\n    static Map<String, Ticket> sTicketMap = new ConcurrentHashMap<String, Ticket>(); \n\n    public static Ticket getTicket(String from ,String to){\n        String key = from + "-" + to;\n        if(sTicketMap.containsKey(key)){\n            System.out.println("\u4f7f\u7528\u7f13\u5b58 ==> " + key);\n            return sTicketMap.get(key);\n        }else{\n            System.out.println("\u521b\u5efa\u5bf9\u8c61 ==> " + key);\n            Ticket ticket = new TrainTicket(from, to);\n            sTicketMap.put(key, ticket);\n            return ticket;\n        }\n\n    }\n}<\/code><\/pre>\n
\u67e5\u8be2\uff1a<\/p>\n
final class Client {\n    public static void main(String[] args) {\n        Ticket ticket01 = TicketFactory.getTicket("\u5317\u4eac", "\u9752\u5c9b");\n        ticket01.showTicketInfo("\u4e0a\u94fa");\n\n        Ticket ticket02 = TicketFactory.getTicket("\u5317\u4eac", "\u9752\u5c9b");\n        ticket02.showTicketInfo("\u4e0b\u94fa");\n\n        Ticket ticket03 = TicketFactory.getTicket("\u5317\u4eac", "\u897f\u5b89");\n        ticket03.showTicketInfo("\u5750\u7968");\n    }\n}<\/code><\/pre>\n
\u7ed3\u679c<\/p>\n
\u521b\u5efa\u5bf9\u8c61 ==> \u5317\u4eac-\u9752\u5c9b\n\u8d2d\u4e70 \u4ece \u5317\u4eac \u5230 \u9752\u5c9b\u7684\u4e0a\u94fa\u706b\u8f66\u7968, \u4ef7\u683c\uff1a71\n\u4f7f\u7528\u7f13\u5b58 ==> \u5317\u4eac-\u9752\u5c9b\n\u8d2d\u4e70 \u4ece \u5317\u4eac \u5230 \u9752\u5c9b\u7684\u4e0b\u94fa\u706b\u8f66\u7968, \u4ef7\u683c\uff1a32\n\u521b\u5efa\u5bf9\u8c61 ==> \u5317\u4eac-\u897f\u5b89\n\u8d2d\u4e70 \u4ece \u5317\u4eac \u5230 \u897f\u5b89\u7684\u5750\u7968\u706b\u8f66\u7968, \u4ef7\u683c\uff1a246<\/code><\/pre>\n
Android\u6e90\u7801\u4e2d\u7684\u5b9e\u73b0<\/h2>\n
    \n
  • Message<\/li>\n<\/ul>\n
    \u56e0\u4e3aAndroid\u662f\u4e8b\u4ef6\u9a71\u52a8\u7684\uff0c\u56e0\u6b64\u5982\u679c\u901a\u8fc7new\u521b\u5efaMessage<\/code>\u5c31\u4f1a\u521b\u5efa\u5927\u91cf\u7684Message<\/code>\u5bf9\u8c61\uff0c\u5bfc\u81f4\u5185\u5b58\u5360\u7528\u7387\u9ad8\uff0c\u9891\u7e41GC\u7b49\u95ee\u9898\u3002\u90a3\u4e48Message<\/code>\u5c31\u91c7\u7528\u4e86\u4eab\u5143\u6a21\u5f0f\u3002
    \nMessage<\/code>\u901a\u8fc7next<\/code>\u6210\u5458\u53d8\u91cf\u4fdd\u6709\u5bf9\u4e0b\u4e00\u4e2aMessage<\/code>\u7684\u5f15\u7528\uff0c\u6700\u540e\u4e00\u4e2a\u53ef\u7528Message<\/code>\u7684next<\/code>\u5219\u4e3a\u7a7a\u3002\u4ece\u800c\u6784\u6210\u4e86\u4e00\u4e2aMessage<\/code>\u94fe\u8868\u3002Message Pool<\/code>\u5c31\u901a\u8fc7\u8be5\u94fe\u8868\u7684\u8868\u5934\u7ba1\u7406\u7740\u6240\u6709\u95f2\u7f6e\u7684Message<\/code>\uff0c\u4e00\u4e2aMessage<\/code>\u5728\u4f7f\u7528\u5b8c\u540e\u53ef\u4ee5\u901a\u8fc7recycle()<\/code>\u65b9\u6cd5\u8fdb\u5165Message Pool<\/code>\uff0c\u5e76\u5728\u9700\u8981\u65f6\u901a\u8fc7obtain<\/code>\u9759\u6001\u65b9\u6cd5\u4eceMessage Pool<\/code>\u83b7\u53d6\u3002Message<\/code>\u627f\u62c5\u4e86\u4eab\u5143\u6a21\u5f0f\u4e2d3\u4e2a\u5143\u7d20\u7684\u804c\u8d23\uff0c\u5373\u662fFlyweight<\/code>\u62bd\u8c61\uff0c\u53c8\u662fConcreateFlyweight<\/code>\u89d2\u8272\uff0c\u540c\u65f6\u53c8\u627f\u62c5\u4e86FlyweightFactoiy<\/code>\u7ba1\u7406\u5bf9\u8c61\u6c60\u7684\u804c\u8d23\u3002<\/p>\n
    \u6240\u4ee5\u4f7f\u7528Message\u63a8\u8350obtain()\uff0c\u4e0d\u8981\u53bbnew\u4e86\u3002<\/p>\n
    \/\/1 \u4f7f\u7528new Message()  \n\/\/Message mess = new Message();  \n\n\/\/2 \u4f7f\u7528Message.obtain()  \nMessage mess = Message.obtain();  \nmess.what = 1;  \n\n\/\/Message mess = mHandler.obtainMessage(1);  \u4e0e\u4e0a\u4e24\u884c\u7684\u4ee3\u7801\u4e00\u6837\uff0c\u53ef\u4ee5\u53c2\u8003\u6e90\u7801\u67e5\u770b  \nmHandler.sendMessage(mess);<\/code><\/pre>\n
    \u603b\u7ed3<\/h2>\n
      \n
    • \u4f18\u70b9<\/li>\n<\/ul>\n
      \uff081\uff09\u5927\u5927\u51cf\u5c11\u5e94\u7528\u7a0b\u5e8f\u521b\u5efa\u7684\u5bf9\u8c61\uff0c\u964d\u4f4e\u7a0b\u5e8f\u5185\u5b58\u7684\u5360\u7528\uff0c\u589e\u5f3a\u7a0b\u5e8f\u7684\u6027\u80fd\u3002
      \n\uff082\uff09\u4f7f\u7528\u4eab\u5143\u6a21\u5f0f\uff0c\u53ef\u4ee5\u8ba9\u4eab\u5143\u5bf9\u8c61\u53ef\u4ee5\u5728\u4e0d\u540c\u7684\u73af\u5883\u4e2d\u88ab\u5171\u4eab\u3002<\/p>\n
        \n
      • \u7f3a\u70b9<\/li>\n<\/ul>\n
        \uff081\uff09\u4f7f\u5f97\u7cfb\u7edf\u66f4\u52a0\u590d\u6742\u3002\u4e3a\u4e86\u4f7f\u5bf9\u8c61\u53ef\u4ee5\u5171\u4eab\uff0c\u9700\u8981\u5c06\u4e00\u4e9b\u72b6\u6001\u5916\u90e8\u5316\uff0c\u8fd9\u4f7f\u5f97\u7a0b\u5e8f\u7684\u903b\u8f91\u590d\u6742\u5316\u3002
        \n\uff082\uff09\u4eab\u5143\u6a21\u5f0f\u5c06\u9700\u3001\u4eab\u5143\u5bf9\u8c61\u7684\u72b6\u6001\u5916\u90e8\u5316\uff0c\u800c\u8bfb\u53d6\u5916\u90e8\u72b6\u6001\u4f7f\u5f97\u8fd0\u884c\u65f6\u95f4\u7a0d\u5fae\u53d8\u957f\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"
        \u4eab\u5143\u6a21\u5f0f\u662f\u7ed3\u6784\u578b\u8bbe\u8ba1\u6a21\u5f0f\u4e4b\u4e00\uff0c\u662f\u5bf9\u5bf9\u8c61\u6c60\u7684\u4e00\u79cd\u5b9e\u73b0\u3002\u5c31\u50cf\u5b83\u7684\u540d\u5b57\u4e00\u6837\uff0c\u5171\u4eab\u5bf9\u8c61\uff0c\u907f\u514d\u91cd\u590d\u7684\u521b\u5efa\u3002\u6211\u4eec\u5e38\u7528\u7684St […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[303],"tags":[],"class_list":["post-1131","post","type-post","status-publish","format-standard","hentry","category-design-pattern"],"_links":{"self":[{"href":"https:\/\/www.appblog.cn\/index.php\/wp-json\/wp\/v2\/posts\/1131","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.appblog.cn\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.appblog.cn\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.appblog.cn\/index.php\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.appblog.cn\/index.php\/wp-json\/wp\/v2\/comments?post=1131"}],"version-history":[{"count":0,"href":"https:\/\/www.appblog.cn\/index.php\/wp-json\/wp\/v2\/posts\/1131\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.appblog.cn\/index.php\/wp-json\/wp\/v2\/media?parent=1131"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.appblog.cn\/index.php\/wp-json\/wp\/v2\/categories?post=1131"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.appblog.cn\/index.php\/wp-json\/wp\/v2\/tags?post=1131"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}