{"id":1117,"date":"2023-03-16T21:19:09","date_gmt":"2023-03-16T13:19:09","guid":{"rendered":"https:\/\/www.appblog.cn\/?p=1117"},"modified":"2023-04-29T11:22:23","modified_gmt":"2023-04-29T03:22:23","slug":"design-pattern-state-mode","status":"publish","type":"post","link":"https:\/\/www.appblog.cn\/index.php\/2023\/03\/16\/design-pattern-state-mode\/","title":{"rendered":"\u8bbe\u8ba1\u6a21\u5f0f\uff088\uff09\u72b6\u6001\u6a21\u5f0f"},"content":{"rendered":"<h2>\u5b9a\u4e49<\/h2>\n<p>\u72b6\u6001\u6a21\u5f0f\u4e2d\u7684\u884c\u4e3a\u662f\u7531\u72b6\u6001\u6765\u51b3\u5b9a\uff0c\u4e0d\u540c\u7684\u72b6\u6001\u4e0b\u6709\u4e0d\u540c\u7684\u884c\u4e3a\u3002\u5f53\u4e00\u4e2a\u5bf9\u8c61\u7684\u5185\u5728\u72b6\u6001\u6539\u53d8\u65f6\u5141\u8bb8\u6539\u53d8\u5176\u884c\u4e3a\uff0c\u8fd9\u4e2a\u5bf9\u8c61\u770b\u8d77\u6765\u50cf\u662f\u6539\u53d8\u4e86\u5176\u7c7b\u3002<\/p>\n<p><!-- more --><\/p>\n<h2>\u4f7f\u7528\u573a\u666f<\/h2>\n<ul>\n<li>\u4e00\u4e2a\u5bf9\u8c61\u7684\u884c\u4e3a\u53d6\u51b3\u4e8e\u5b83\u7684\u72b6\u6001\uff0c\u5e76\u4e14\u5b83\u5fc5\u987b\u5728\u8fd0\u884c\u65f6\u6839\u636e\u72b6\u6001\u6539\u53d8\u5b83\u7684\u884c\u4e3a\u3002 <\/li>\n<li>\u4ee3\u7801\u4e2d\u5305\u542b\u5927\u91cf\u4e0e\u5bf9\u8c61\u72b6\u6001\u6709\u5173\u7684\u6761\u4ef6\u8bed\u53e5\uff0c\u4f8b\u5982\uff0c\u4e00\u4e2a\u64cd\u4f5c\u4e2d\u542b\u6709\u5927\u91cf\u7684\u591a\u5206\u652f\u8bed\u53e5\uff0c\u4e14\u8fd9\u4e9b\u5206\u652f\u4f9d\u8d56\u4e8e\u8be5\u5bf9\u8c61\u7684\u72b6\u6001\u3002<\/li>\n<\/ul>\n<h2>\u7b80\u5355\u5b9e\u73b0<\/h2>\n<p>\u5b9e\u73b0\u6548\u679c\uff1a\u9996\u5148\u5c06\u7535\u89c6\u7684\u72b6\u6001\u5206\u4e3a\u5f00\u673a\u4e0e\u5173\u673a\u72b6\u6001\uff0c\u5f00\u673a\u65f6\u53ef\u4ee5\u901a\u8fc7\u9065\u63a7\u5668\u5b9e\u73b0\u9891\u9053\u5207\u6362\u548c\u8c03\u8282\u97f3\u91cf\uff0c\u4f46\u662f\u5173\u673a\u65f6\uff0c\u8fd9\u4e9b\u64cd\u4f5c\u90fd\u4f1a\u5931\u6548\u3002<\/p>\n<p>\u9996\u5148\u662f\u666e\u901a\u7684\u5b9e\u73b0\u65b9\u6cd5\uff1a<\/p>\n<pre><code class=\"language-java\">public class TVController {\n    \/\/\u5f00\u673a\u72b6\u6001\n    private final static int POWER_ON = 1;\n    \/\/\u5173\u673a\u72b6\u6001\n    private final static int POWER_OFF = 2; \n    \/\/\u9ed8\u8ba4\u72b6\u6001\n    private int mState = POWER_OFF;\n\n    public void powerOn() {\n        if (mState == POWER_OFF) {\n            System.out.println(&quot;\u7535\u89c6\u5f00\u673a\u4e86&quot;);\n        }\n        mState = POWER_ON;\n    }\n\n    public void powerOff() {\n        if (mState ==POWER_ON) {\n            System.out.println(&quot;\u7535\u89c6\u5173\u673a\u4e86&quot;);\n        }\n        mState = POWER_OFF;\n    }\n\n    public void nextChannel() {\n        if (mState == POWER_ON) {\n            System.out.println(&quot;\u4e0b\u4e00\u9891\u9053&quot;);\n        } else {\n            System.out.println(&quot;\u6ca1\u6709\u5f00\u673a&quot;);\n        }\n    }\n\n    public void prevChannel() {\n        if (mState == POWER_ON) {\n            System.out.println(&quot;\u4e0a\u4e00\u9891\u9053&quot;);\n        } else {\n            System.out.println(&quot;\u6ca1\u6709\u5f00\u673a&quot;);\n        }\n    }\n\n    public void turnUp() {\n        if (mState == POWER_ON) {\n            System.out.println(&quot;\u8c03\u9ad8\u97f3\u91cf&quot;);\n        } else {\n            System.out.println(&quot;\u6ca1\u6709\u5f00\u673a&quot;);\n        }\n    }\n\n    public void turnDown() {\n        if (mState == POWER_ON) {\n            System.out.println(&quot;\u8c03\u4f4e\u97f3\u91cf&quot;);\n        } else {\n            System.out.println(&quot;\u6ca1\u6709\u5f00\u673a&quot;);\n        }\n    }\n}<\/code><\/pre>\n<p>\u53ef\u4ee5\u770b\u5230\uff0c\u6bcf\u6b21\u6267\u884c\u901a\u8fc7\u5224\u65ad\u5f53\u524d\u72b6\u6001\u6765\u8fdb\u884c\u64cd\u4f5c\uff0c\u90e8\u5206\u7684\u4ee3\u7801\u91cd\u590d\uff0c\u5047\u8bbe\u72b6\u6001\u548c\u529f\u80fd\u589e\u52a0\uff0c\u5c31\u4f1a\u8d8a\u6765\u8d8a\u96be\u4ee5\u7ef4\u62a4\u3002\u8fd9\u65f6\u53ef\u4ee5\u4f7f\u7528\u72b6\u6001\u6a21\u5f0f\uff0c\u5982\u4e0b\uff1a<\/p>\n<p>\u7535\u89c6\u7684\u64cd\u4f5c<\/p>\n<pre><code class=\"language-java\">\/**\n * \u7535\u89c6\u72b6\u6001\u63a5\u53e3\uff0c\u5b9a\u4e49\u4e86\u7535\u89c6\u7684\u64cd\u4f5c\u51fd\u6570\n * \n * *\/\npublic interface TVState {\n\n    public void nextChannel();\n    public void prevChannel();\n    public void turnUp();\n    public void turnDown();\n\n}<\/code><\/pre>\n<p>\u5173\u673a\u72b6\u6001<\/p>\n<pre><code class=\"language-java\">\/**\n * \n * \u5173\u673a\u72b6\u6001\uff0c\u64cd\u4f5c\u65e0\u7ed3\u679c\n * \n * *\/\npublic class PowerOffState implements TVState {\n\n    @Override\n    public void nextChannel() {\n\n    }\n\n    @Override\n    public void prevChannel() {\n\n    }\n\n    @Override\n    public void turnUp() {\n\n    }\n\n    @Override\n    public void turnDown() {\n\n    }\n}<\/code><\/pre>\n<p>\u5f00\u673a\u72b6\u6001<\/p>\n<pre><code class=\"language-java\">\/**\n * \n * \u5f00\u673a\u72b6\u6001\uff0c\u64cd\u4f5c\u6709\u6548\n * \n * *\/\npublic class PowerOnState implements TVState {\n\n    @Override\n    public void nextChannel() {\n        System.out.println(&quot;\u4e0b\u4e00\u9891\u9053&quot;);\n    }\n\n    @Override\n    public void prevChannel() {\n        System.out.println(&quot;\u4e0a\u4e00\u9891\u9053&quot;);\n    }\n\n    @Override\n    public void turnUp() {\n        System.out.println(&quot;\u8c03\u9ad8\u97f3\u91cf&quot;);\n    }\n\n    @Override\n    public void turnDown() {\n        System.out.println(&quot;\u8c03\u4f4e\u97f3\u91cf&quot;);\n    }\n}<\/code><\/pre>\n<p>\u7535\u6e90\u64cd\u4f5c\u63a5\u53e3<\/p>\n<pre><code class=\"language-java\">\/**\n * \u7535\u6e90\u64cd\u4f5c\u63a5\u53e3\n * \n * *\/\npublic interface PowerController {\n    public void powerOn();\n\n    public void powerOff();\n}<\/code><\/pre>\n<p>\u7535\u89c6\u9065\u63a7\u5668<\/p>\n<pre><code class=\"language-java\">\/**\n * \u7535\u89c6\u9065\u63a7\u5668\n * \n **\/\npublic class TVController implements PowerController {\n\n    TVState mTVState;\n\n    public void setTVState(TVState mTVState) {\n        this.mTVState = mTVState;\n    }\n\n    @Override\n    public void powerOn() {\n        setTVState(new PowerOnState());\n        System.out.println(&quot;\u5f00\u673a\u4e86&quot;);\n    }\n\n    @Override\n    public void powerOff() {\n        setTVState(new PowerOffState());\n        System.out.println(&quot;\u5173\u673a\u4e86&quot;);\n    }\n\n    public void nextChannel() {\n        mTVState.nextChannel();\n    }\n\n    public void prevChannel() {\n        mTVState.prevChannel();\n    }\n\n    public void turnUp() {\n        mTVState.turnUp();\n    }\n\n    public void turnDown() {\n        mTVState.turnDown();\n    }\n}<\/code><\/pre>\n<p>\u8c03\u7528\uff1a<\/p>\n<pre><code class=\"language-java\">public class Client {\n    public static void main(String[] args) {\n        TVController tvController = new TVController();\n        \/\/\u8bbe\u7f6e\u5f00\u673a\u72b6\u6001\n        tvController.powerOn();\n        \/\/\u4e0b\u4e00\u9891\u9053\n        tvController.nextChannel();\n        \/\/\u8c03\u9ad8\u97f3\u91cf\n        tvController.turnUp();\n        \/\/\u5173\u673a\n        tvController.powerOff();\n        \/\/\u8c03\u4f4e\u97f3\u91cf\uff0c\u6b64\u65f6\u4e0d\u4f1a\u751f\u6548\n        tvController.turnDown();\n    }\n}<\/code><\/pre>\n<p>\u7ed3\u679c<\/p>\n<pre><code>\u5f00\u673a\u4e86\n\u4e0b\u4e00\u9891\u9053\n\u8c03\u9ad8\u97f3\u91cf\n\u5173\u673a\u4e86<\/code><\/pre>\n<p>\u53ef\u4ee5\u770b\u51fa\uff0c\u72b6\u6001\u6a21\u5f0f\u5c06\u8fd9\u4e9b\u884c\u4e3a\u5c01\u88c5\u5230\u72b6\u6001\u7c7b\u4e2d\uff0c\u5728\u8fdb\u884c\u64cd\u4f5c\u65f6\u5c06\u8fd9\u4e9b\u529f\u80fd\u8f6c\u53d1\u7ed9\u72b6\u6001\u5bf9\u8c61\uff0c\u4e0d\u540c\u7684\u72b6\u6001\u6709\u4e0d\u540c\u7684\u5b9e\u73b0\uff0c\u53bb\u9664\u4e86\u91cd\u590d\u4e86if-else\u8bed\u53e5\uff0c\u8fd9\u6b63\u662f\u72b6\u6001\u6a21\u5f0f\u7684\u7cbe\u9ad3\u6240\u5728\u3002<\/p>\n<h2>\u4e0e\u7b56\u7565\u6a21\u5f0f\u7684\u533a\u522b<\/h2>\n<p>\u72b6\u6001\u6a21\u5f0f\u4e0e\u7b56\u7565\u6a21\u5f0f\u7684\u7ed3\u6784\u51e0\u4e4e\u662f\u4e00\u6837\u7684\uff0c\u5c31\u50cf\u662f\u5b6a\u751f\u5144\u5f1f\u3002\u4f46\u662f\u4ed6\u4eec\u7684\u76ee\u5730\u3001\u672c\u8d28\u4e0d\u4e00\u6837\u3002\u72b6\u6001\u6a21\u5f0f\u7684\u884c\u4e3a\u662f\u5e73\u884c\u7684\u3001\u4e0d\u53ef\u66ff\u6362\u7684\uff0c\u7b56\u7565\u6a21\u5f0f\u7684\u884c\u4e3a\u662f\u5f7c\u6b64\u72ec\u7acb\u7684\u3001\u53ef\u76f8\u4e92\u66ff\u6362\u7684\u3002\u72b6\u6001\u6a21\u5f0f\uff0c\u901a\u5e38\u662f\u81ea\u6211\u63a7\u5236\u72b6\u6001\u7684\u6539\u53d8\u3002\u800c\u7b56\u7565\u6a21\u5f0f\uff0c\u662f\u7531\u5916\u90e8\u6307\u5b9a\u4f7f\u7528\u4ec0\u4e48\u6837\u7684\u7b56\u7565\u3002<\/p>\n<h2>Android\u5b9e\u6218\u4e2d\u7684\u4f7f\u7528<\/h2>\n<ul>\n<li>\u767b\u5f55\u7cfb\u7edf\uff0c\u6839\u636e\u7528\u6237\u662f\u5426\u767b\u5f55\uff0c\u5224\u65ad\u4e8b\u4ef6\u7684\u5904\u7406\u65b9\u5f0f<\/li>\n<li>Wi-Fi\u7ba1\u7406\uff0c\u5728\u4e0d\u540c\u7684\u72b6\u6001\u4e0b\uff0cWiFi\u7684\u626b\u63cf\u8bf7\u6c42\u5904\u7406\u4e0d\u4e00<\/li>\n<\/ul>\n<h2>\u603b\u7ed3<\/h2>\n<p>\uff081\uff09\u4f18\u70b9<\/p>\n<p>\u5c06\u6240\u6709\u4e0e\u4e00\u4e2a\u7279\u5b9a\u7684\u72b6\u6001\u76f8\u5173\u7684\u884c\u4e3a\u90fd\u653e\u5165\u4e00\u4e2a\u72b6\u6001\u5bf9\u8c61\u4e2d\uff0c\u5b83\u63d0\u4f9b\u4e86\u4e00\u4e2a\u66f4\u597d\u7684\u65b9\u6cd5\u6765\u7ec4\u7ec7\u4e0e\u7279\u5b9a\u72b6\u6001\u76f8\u5173\u7684\u4ee3\u7801\uff0c\u5c06\u7e41\u7410\u7684\u72b6\u6001\u5224\u65ad\u8f6c\u6362\u6210\u7ed3\u6784\u6e05\u6670\u7684\u72b6\u6001\u7c7b\u65cf\uff0c\u5728\u907f\u514d\u4ee3\u7801\u81a8\u80c0\u7684\u540c\u65f6\u4e5f\u4fdd\u8bc1\u4e86\u53ef\u6269\u5c55\u6027\u4e0e\u53ef\u7ef4\u62a4\u6027\u3002<\/p>\n<p>\uff082\uff09\u7f3a\u70b9<\/p>\n<p>\u72b6\u6001\u6a21\u5f0f\u7684\u4f7f\u7528\u5fc5\u7136\u4f1a\u589e\u52a0\u7cfb\u7edf\u7c7b\u548c\u5bf9\u8c61\u7684\u4e2a\u6570\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"<p>\u5b9a\u4e49 \u72b6\u6001\u6a21\u5f0f\u4e2d\u7684\u884c\u4e3a\u662f\u7531\u72b6\u6001\u6765\u51b3\u5b9a\uff0c\u4e0d\u540c\u7684\u72b6\u6001\u4e0b\u6709\u4e0d\u540c\u7684\u884c\u4e3a\u3002\u5f53\u4e00\u4e2a\u5bf9\u8c61\u7684\u5185\u5728\u72b6\u6001\u6539\u53d8\u65f6\u5141\u8bb8\u6539\u53d8\u5176\u884c\u4e3a\uff0c\u8fd9\u4e2a [&hellip;]<\/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-1117","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\/1117","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=1117"}],"version-history":[{"count":0,"href":"https:\/\/www.appblog.cn\/index.php\/wp-json\/wp\/v2\/posts\/1117\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.appblog.cn\/index.php\/wp-json\/wp\/v2\/media?parent=1117"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.appblog.cn\/index.php\/wp-json\/wp\/v2\/categories?post=1117"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.appblog.cn\/index.php\/wp-json\/wp\/v2\/tags?post=1117"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}