{"id":1385,"date":"2023-06-27T13:54:39","date_gmt":"2023-06-27T05:54:39","guid":{"rendered":"https:\/\/xinchewhd.com.cn\/?p=1385"},"modified":"2023-06-27T13:54:39","modified_gmt":"2023-06-27T05:54:39","slug":"%e8%8a%b1%e5%87%a0%e5%88%86%e9%92%9f%e5%bf%ab%e9%80%9f%e4%ba%86%e8%a7%a3%e4%b8%80%e4%b8%8b%e6%b3%9b%e5%9e%8b%e4%b8%8e%e6%9e%9a%e4%b8%be%ef%bc%88%e6%9c%89%e6%89%8b%e5%b0%b1%e4%bc%9a%ef%bc%89","status":"publish","type":"post","link":"https:\/\/xinchewhd.com.cn\/index.php\/java\/%e8%8a%b1%e5%87%a0%e5%88%86%e9%92%9f%e5%bf%ab%e9%80%9f%e4%ba%86%e8%a7%a3%e4%b8%80%e4%b8%8b%e6%b3%9b%e5%9e%8b%e4%b8%8e%e6%9e%9a%e4%b8%be%ef%bc%88%e6%9c%89%e6%89%8b%e5%b0%b1%e4%bc%9a%ef%bc%89\/","title":{"rendered":"\u82b1\u51e0\u5206\u949f\u5feb\u901f\u4e86\u89e3\u4e00\u4e0b\u6cdb\u578b\u4e0e\u679a\u4e3e\uff08\u6709\u624b\u5c31\u4f1a\uff09"},"content":{"rendered":"
\n
\n

Java\u679a\u4e3e\u4e0e\u6cdb\u578b<\/span><\/h1>\n

\u524d\u8a00<\/span><\/h2>\n

\u672c\u8282\u7ed9\u5927\u5bb6\u8bb2\u8bb2 \u300c\u679a\u4e3e\u4e0e\u6cdb\u578b<\/span>\u300d<\/strong> \uff0c\u672c\u7bc7\u5185\u5bb9\u4e3b\u8981\u5305\u62ec\u4ee5\u4e0b\u51e0\u4e2a\u90e8\u5206:<\/p>\n

    \n
  • \n
    \u679a\u4e3e\u5b9a\u4e49\u548c\u4f7f\u7528<\/section>\n<\/li>\n
  • \n
    \u6cdb\u578b\u8bb2\u89e3<\/section>\n<\/li>\n
  • \n
    \u4ee3\u7801\u5b9e\u64cd<\/section>\n<\/li>\n
  • \n
    \u5e38\u89c1\u7684\u6cdb\u578b\u95ee\u9898<\/section>\n<\/li>\n<\/ul>\n

    \u679a\u4e3e<\/span><\/h2>\n

    \u5b9a\u4e49<\/span><\/h3>\n

    \u5565\u662f\u679a\u4e3e?\u4ece\u5b9a\u4e49\u6765\u8bb2\u679a\u4e3e\u5c31\u662f\u60c5\u51b5\u7684\u5404\u79cd\u7f57\u5217\uff0c\u5728java\u4e2d\u5b83\u662f\u4e00\u79cd\u7279\u6b8a\u7684\u7c7b\uff0c\u4e00\u822c\u8868\u793a\u4e00\u7ec4\u5e38\u91cf\uff0c\u4e3e\u4e2a\u4f8b\u5b50:<\/p>\n

    <\/span>enum<\/span> Color 
    { 
        RED, BLUE; 
    } 
    <\/code><\/pre>\n
    \u4e0a\u8ff0\u4ee3\u7801\uff0c\u679a\u4e3e\u4e86\u989c\u8272\u7684\u4e24\u79cd\u6210\u5458\uff0c\u5206\u522b\u662f RED, BLUE<\/code>\uff0c\u679a\u4e3e\u4e5f\u53ef\u4ee5\u5b9a\u4e49\u5728\u7c7b\u4e2d\uff0c\u6211\u4eec\u8f93\u51fa\u4e00\u4e0b:<\/p>\n
    <\/span>public<\/span> class<\/span> EnumTest<\/span>
    <\/span>{
        enum<\/span> Color
        {
            RED, GREEN, BLUE;
        }
     
        \/\/ \u6267\u884c\u8f93\u51fa\u7ed3\u679c<\/span>
        public<\/span> static<\/span> void<\/span> main<\/span>(String[] args)<\/span>
        <\/span>{
            Color c = Color.RED;
            System.out.println(c); \/\/ RED<\/span>
        }
    }
    <\/code><\/pre>\n
    \u7ed3\u679c\u8fd4\u56de RED<\/code><\/p>\n
    \u904d\u5386\u679a\u4e3e<\/span><\/h3>\n
    \u5982\u4f55\u53bb\u904d\u5386\u5b83\u7684\u6210\u5458\u5462\uff1f<\/p>\n
    <\/span>public<\/span> class<\/span> EnumTest<\/span>
    <\/span>{
        enum<\/span> Color
        {
            RED, GREEN, BLUE;
        }
     
        \/\/ \u6267\u884c\u8f93\u51fa\u7ed3\u679c<\/span>
        public<\/span> static<\/span> void<\/span> main<\/span>(String[] args)<\/span>
        <\/span>{
            for<\/span> (Color c : Color.values()) {
                System.out.println(c);
                \/\/ RED<\/span>
                \/\/ GREEN<\/span>
                \/\/ BLUE<\/span>
            }
        }
    }
    <\/code><\/pre>\n
    \u4f5c\u4e3a\u6761\u4ef6\u4f7f\u7528<\/span><\/h3>\n
    \u6211\u4eec\u4e5f\u53ef\u4ee5\u7528\u4f5c\u6761\u4ef6\u4f7f\u7528\uff0c\u8fd9\u6837\u4ee3\u7801\u53ef\u8bfb\u6027\u4f1a\u53d8\u9ad8\u4e00\u70b9<\/p>\n
    <\/span>public<\/span> class<\/span> EnumTest<\/span>
    <\/span>{
        enum<\/span> Color
        {
            RED, GREEN, BLUE;
        }
     
        \/\/ \u6267\u884c\u8f93\u51fa\u7ed3\u679c<\/span>
        public<\/span> static<\/span> void<\/span> main<\/span>(String[] args)<\/span>
        <\/span>{
            Color c = Color.BLUE;

            switch<\/span>(c) {
                case<\/span> RED:
                    System.out.println(\"\u7ea2\u8272\"<\/span>);
                    break<\/span>;
                case<\/span> GREEN:
                    System.out.println(\"\u7eff\u8272\"<\/span>);
                    break<\/span>;
                case<\/span> BLUE:
                    System.out.println(\"\u84dd\u8272\"<\/span>);
                    break<\/span>;
                }
            }
    }
    <\/code><\/pre>\n
    \u8fdb\u9636\u7528\u6cd5<\/span><\/h3>\n
    \u4e3e\u4e00\u4e2a\u5e38\u7528\u7684\u4f8b\u5b50\uff0c\u6211\u4eec\u5728\u505aAPI\u8bf7\u6c42\u8fd4\u56de\u54cd\u5e94\u7ed3\u679c\u65f6\uff0c\u6211\u4eec\u53ef\u4ee5\u5229\u7528\u679a\u4e3e\u53bb\u5b9a\u4e49\u6211\u4eec\u7684\u54cd\u5e94\u4f53\uff0c\u6839\u636e\u4e0d\u540c\u7684\u53d8\u91cf\uff0c\u8fd4\u56de\u54cd\u5e94\u7684\u7ed3\u679c\u3002\u6765\u770b\u4e00\u4e2a\u6211\u5199\u597d\u7684\u4f8b\u5b50:<\/p>\n
    <\/span>public<\/span> enum<\/span> Response implements ResponseInter {
        SUCCESS(200<\/span>, null<\/span>, \"success\"<\/span>),
        Fail(0<\/span>, null<\/span>, \"\u9519\u8bef\"<\/span>),
        Response(0<\/span>, null<\/span>, \"\"<\/span>);

        private<\/span> String msg;
        private<\/span> Integer code;
        private<\/span> Object data;

        Response(int<\/span> code, String data, String msg) {
            this<\/span>.code = code;
            this<\/span>.msg = msg;
            this<\/span>.data = data;
        }

        public<\/span> String getMsg<\/span>()<\/span> <\/span>{
            return<\/span> msg;
        }

        public<\/span> void<\/span> setMsg<\/span>(String msg)<\/span> <\/span>{
            this<\/span>.msg = msg;
        }

        public<\/span> Integer getCode<\/span>()<\/span> <\/span>{
            return<\/span> code;
        }

        public<\/span> void<\/span> setCode<\/span>(Integer code)<\/span> <\/span>{
            this<\/span>.code = code;
        }

        public<\/span> Object getData<\/span>()<\/span> <\/span>{
            return<\/span> data;
        }

        public<\/span> void<\/span> setData<\/span>(Object data)<\/span> <\/span>{
            this<\/span>.data = data;
        }

        @Override<\/span>
        public<\/span> ResponseData response<\/span>(int<\/span> code, String data, String msg)<\/span> <\/span>{
            this<\/span>.code = code;
            this<\/span>.msg = msg;
            this<\/span>.data = data;
            return<\/span> getResponse();
        }

        private<\/span> ResponseData getResponse<\/span>()<\/span> <\/span>{
            ResponseData response = new<\/span> ResponseData();
            response.setData(this<\/span>.data);
            response.setCode(this<\/span>.code);
            response.setMsg(this<\/span>.msg);
            return<\/span> response;
        }

        public<\/span> ResponseData success<\/span>()<\/span> <\/span>{
           return<\/span> getResponse();
        }

        public<\/span> ResponseData fail<\/span>()<\/span> <\/span>{
            return<\/span> getResponse();
        }

    }
    <\/code><\/pre>\n
    \u300c\u679a\u4e3e\u4e5f\u662f\u4e00\u79cd\u7279\u6b8a\u7684\u7c7b<\/span>\u300d<\/strong> ,\u6240\u4ee5\u5b83\u4e5f\u53ef\u4ee5\u5b9e\u73b0\u63a5\u53e3\u3002\u5f53\u6211\u4eec\u5b9a\u4e49SUCCESS(200, null, \"success\")<\/code>\u8fd9\u79cd\u5e26\u62ec\u53f7\u7684\u6210\u5458\u65f6\uff0cidea<\/code>\u4f1a\u81ea\u52a8\u63d0\u793a\u4f60\u53bb\u521b\u5efa\u5b83\u7684\u6784\u9020\u51fd\u6570\uff0c\u6240\u4ee5\u540e\u8fb9\u6211\u4eec\u53ef\u4ee5\u53d6\u5b9e\u4f8b\u5316\u5b83\u3002<\/p>\n
    <\/span>@FunctionalInterface<\/span> \/\/ \u51fd\u6570\u5f0f\u63a5\u53e3<\/span>
    public<\/span> interface<\/span> ResponseInter<\/span> <\/span>{
        ResponseData response<\/span>(int<\/span> code, String data, String msg)<\/span><\/span>;
    }
    <\/code><\/pre>\n
    \u8fd9\u91cc\u63d2\u4e00\u4e2a\u5c0f\u77e5\u8bc6\u70b9\uff0c@FunctionalInterface<\/code> \u300c\u8868\u793a\u51fd\u6570\u5f0f\u63a5\u53e3<\/span>\u300d<\/strong>, \u6210\u5458\u5185\u90e8\u53ea\u80fd\u6709\u4e00\u4e2a\u63a5\u53e3\u65b9\u6cd5\u3002<\/p>\n
    \u5982\u4f55\u4f7f\u7528?<\/p>\n
    <\/span>public<\/span> class<\/span> EnumMain<\/span> <\/span>{

        public<\/span> static<\/span> void<\/span> main<\/span>(String[] args)<\/span> <\/span>{
            Response response = Response.SUCCESS;
            String res = JSON.toJSONString(response.success());
            Log.info(res); \/\/ {\"code\":200,\"msg\":\"success\"}<\/span>

            Response response1 = Response.Fail;
            String res1 = JSON.toJSONString(response1.fail());
            Log.info(res1); \/\/{\"code\":0,\"msg\":\"\u9519\u8bef\"}<\/span>

            Response response2 = Response.Response;
            String res2 = JSON.toJSONString(response2.response(200<\/span>, \"\u8fd9\u662f\u6570\u636e\"<\/span>, \"success\"<\/span>));
            Log.info(res2); \/\/ {\"code\":200,\"data\":\"\u8fd9\u662f\u6570\u636e\",\"msg\":\"success\"}<\/span>
        }

    }
    <\/code><\/pre>\n
    \u662f\u4e0d\u662f\u5f88\u7b80\u5355\uff0c\u8fd9\u91cc\u6211\u53ea\u662f\u7c97\u7565\u7684\u5b9a\u4e49\u4e86\u4e00\u4e0b\uff0c\u5176\u5b9e\u8fd8\u53ef\u4ee5\u7ee7\u7eed\u6df1\u5165\u4e0b\u53bb\uff0c\u6bd4\u5982\u6211\u4eec\u5b9a\u4e49\u5404\u79cd\u60c5\u51b5\u4e0b\u8bf7\u6c42\u7684\u72b6\u6001\u7801\uff0c\u8fd9\u6837\u4e00\u6765\uff0c\u5c31\u4e0d\u7528\u6211\u4eec\u6bcf\u6b21\u624b\u52a8\u586b\u5199\u5177\u4f53\u7684\u503c\u4e86\u3002<\/p>\n
    \u6cdb\u578b<\/span><\/h2>\n
    \u4ece\u5b57\u9762\u610f\u601d\u8bb2\uff0c\u4e0d\u786e\u5b9a\u7684\u7c7b\u578b\u3002\u6709\u65f6\u5019\u6211\u4eec\u5728\u5199\u4ee3\u7801\u65f6\uff0c\u4f20\u53c2\u90fd\u9700\u8981\u5b9a\u4e49\u5177\u4f53\u7684\u7c7b\u578b\uff0c\u4e0d\u7136\u7f16\u8bd1\u4f1a\u62a5\u9519\uff0c\u4f46\u662f\u6709\u4e9b\u60c5\u51b5\u6211\u4eec\u9700\u8981\u590d\u7528\u6211\u4eec\u7684\u4ee3\u7801\uff0c\u4f46\u662f\u7531\u4e8e\u5f3a\u7c7b\u578b\u7684\u8981\u6c42\u4e0b\uff0c\u6211\u4eec\u4e0d\u5f97\u5df2\u53bb\u5728\u5b9a\u4e49\u8fd9\u6837\u7684\u7c7b\uff0c\u8fd9\u6837\u663e\u5f97\u5f88\u9ebb\u70e6\uff0c\u6240\u4ee5\u8fd9\u65f6\u5019\u6cdb\u578b\uff0c\u5c31\u6709\u5f88\u5927\u7684\u4f5c\u7528\u4e86\u3002<\/p>\n
    \u5b9a\u4e49<\/span><\/h3>\n
    \u5148\u770b\u6700\u7b80\u5355\u7684\u4e00\u4e2a\u4f8b\u5b50\u4f53\u4f1a\u4e00\u4e0b:<\/p>\n
    <\/span>@Data<\/span>
    public<\/span> class<\/span> ClassMain<\/span> <T<\/span>> <\/span>{
        private<\/span> T name;
    }
    <\/code><\/pre>\n
    \u300c\u6cdb\u578b\u7c7b\u300d<\/strong> \u578b\u5728\u903b\u8f91\u4e0a\u770b\u4ee5\u770b\u6210\u662f\u591a\u4e2a\u4e0d\u540c\u7684\u7c7b\u578b\uff0c\u5b9e\u9645\u4e0a\u90fd\u662f\u76f8\u540c\u7684\u57fa\u672c\u7c7b\u578b\u3002\u901a\u5e38\u4f7f\u7528T\u6765\u4ee3\u8868\u67d0\u79cd\u7c7b\u578b\uff0c T\u4e0d\u662f\u7edd\u5bf9\u7684\uff0c\u53ef\u4ee5\u662f\u4efb\u610f\u3002<\/p>\n
    \u5982\u4f55\u4f7f\u7528, \u7c7b\u540d<\u7c7b\u578b>:<\/p>\n
    <\/span>ClassMain<String> f = new<\/span> ClassMain<>();
    f.setName(\"haha\"<\/span>);
    Log.info(f.getName().getClass()); \/\/ class java.lang.String<\/span>
    <\/code><\/pre>\n
    \u6cdb\u578b\u63a5\u53e3<\/span><\/h3>\n
    \u6cdb\u578b\u63a5\u53e3\u4f7f\u7528\u8fd8\u662f\u6bd4\u8f83\u591a\u7684\uff0c\u770b\u4e00\u4e2a\u4f8b\u5b50:<\/p>\n
    <\/span>public<\/span> interface<\/span> InterfaceMain<\/span><T<\/span>> <\/span>{
        T hello<\/span>(ClassMain<T> ...obj)<\/span><\/span>;
    }
    <\/code><\/pre>\n
    <\/span>@Data<\/span>
    public<\/span> class<\/span> ClassMain<\/span> <T<\/span>> implements<\/span> InterfaceMain<\/span> <T<\/span>> <\/span>{
        private<\/span> T name;

        @Override<\/span>
        public<\/span> T hello<\/span>(ClassMain<T> ...obj)<\/span> <\/span>{
            return<\/span> this<\/span>.name;
        }
    }
    <\/code><\/pre>\n
    ...obj<\/code>\u8fd9\u4e2a\u8868\u793a\u4e0d\u5b9a\u53c2\u6570\uff0c\u610f\u601d\u662f\u8bf4\u4f60\u53ef\u4ee5\u4f20\u591a\u4e2a\u540c\u7c7b\u578b\u7684\u53c2\u6570\u3002<\/p>\n
    \u6cdb\u578b\u901a\u914d\u7b26<\/span><\/h3>\n
    \u6709\u65f6\u5019\u4f60\u5728\u4f7f\u7528\u522b\u4eba\u5199\u597d\u7684\u7c7b\u65f6\uff0c\u7ecf\u5e38\u770b\u5230\uff1f<\/code>\u8fd9\u6837\u7684\u6807\u8bb0, \u5b83\u8868\u793a\u4e00\u4e9b\u4e0d\u786e\u5b9a\u7684\u7c7b\u578b\uff1a<\/p>\n
    <\/span> \/\/ \u6cdb\u578b\u901a\u914d\u7b26<\/span>
    \/\/ \u9002\u5408\u4e00\u4e9b\u4e0d\u786e\u5b9a\u7684\u7c7b\u578b<\/span>
    public<\/span> T hello1<\/span>(ClassMain<?> obj)<\/span> <\/span>{
        return<\/span> this<\/span>.name;
    }
    <\/code><\/pre>\n
    \u6cdb\u578b\u65b9\u6cd5<\/span><\/h3>\n
    \u901a\u8fc7\u4e00\u4e2a\u4f8b\u5b50\u611f\u53d7\u4e00\u4e0b:<\/p>\n
    <\/span>public<\/span> class<\/span> MethodMain<\/span> <T<\/span>> <\/span>{

        private<\/span> T name;

        public<\/span> <T> T hello<\/span>(MethodMain<T> obj)<\/span> <\/span>{
            return<\/span> obj.getMsg(obj.name);
        }

        public<\/span> T getMsg<\/span>(T name)<\/span> <\/span>{
            return<\/span> name;
        }

        public<\/span> <T> void<\/span> getMsg<\/span>(T ...arg)<\/span> <\/span>{
            for<\/span>(T args :arg) {
                Log.info(\"\u6cdb\u578b\u53ef\u53d8\u53c2 --->\"<\/span> + args);
            }
        }

        \/\/ \u9759\u6001\u65b9\u6cd5\u4f7f\u7528\u6cdb\u578b\u65f6\uff0c\u9700\u8981\u5b9a\u4e49\u6210\u6cdb\u578b\u65b9\u6cd5, \u5e76\u4e14\u4e0e\u5b9a\u4e49\u7c7b\u65e0\u5173<\/span>
        public<\/span> static<\/span> <T> void<\/span> get1<\/span>(T ...arg)<\/span> <\/span>{
            Log.info(arg.getClass().getName());
        }

        \/\/ \u6cdb\u578b\u4e2d\u7684\u8fb9\u754c<\/span>
        \/\/ extends \u7ee7\u627f String \u7c7b\u578b<\/span>
        \/\/ \u8fd8\u6709\u4e00\u4e2a\u662f super \u53cd\u4e4b<\/span>
        public<\/span> static<\/span> <T extends String> void<\/span> get2<\/span>(T ...arg)<\/span> <\/span>{
            Log.info(arg.getClass().getName());
        }

    }
    <\/code><\/pre>\n
    <T extends String><\/code>\u8fd9\u79cd\u901a\u5e38\u53eb \u300c\u6cdb\u578b\u8fb9\u754c\u300d<\/strong>, \u5e38\u7528\u6765\u7ea6\u675f\u6211\u4eec\u7684\u6cdb\u578b\uff0c\u4f7f\u5b83\u4e25\u8c28\u4e00\u4e9b\u3002<\/p>\n
    \u6cdb\u578b\u4e00\u95ee\u4e00\u7b54\u2753<\/span><\/h3>\n
      \n
    • \n
      Java\u4e2d\u7684\u6cdb\u578b\u662f\u4ec0\u4e48 ? \u4f7f\u7528\u6cdb\u578b\u7684\u597d\u5904\u662f\u4ec0\u4e48?<\/section>\n<\/li>\n<\/ul>\n
      \u6cdb\u578b\u9632\u6b62\u4e86\u90a3\u79cd\u60c5\u51b5\u7684\u53d1\u751f,\u5b83\u63d0\u4f9b\u4e86\u7f16\u8bd1\u671f\u7684\u7c7b\u578b\u5b89\u5168\uff0c\u786e\u4fdd\u4f60\u53ea\u80fd\u628a\u6b63\u786e\u7c7b\u578b\u7684\u5bf9\u8c61\u653e\u5165\u96c6\u5408\u4e2d\uff0c\u907f\u514d\u4e86\u5728\u8fd0\u884c\u65f6\u51fa\u73b0ClassCastException<\/code>\u3002<\/p>\n
        \n
      • \n
        Java\u7684\u6cdb\u578b\u662f\u5982\u4f55\u5de5\u4f5c\u7684 ? \u4ec0\u4e48\u662f\u7c7b\u578b\u64e6\u9664 ?<\/section>\n<\/li>\n<\/ul>\n
        \u6cdb\u578b\u662f\u901a\u8fc7\u7c7b\u578b\u64e6\u9664\u6765\u5b9e\u73b0\u7684\uff0c\u7f16\u8bd1\u5668\u5728\u7f16\u8bd1\u65f6\u64e6\u9664\u4e86\u6240\u6709\u7c7b\u578b\u76f8\u5173\u7684\u4fe1\u606f\uff0c\u6240\u4ee5\u5728\u8fd0\u884c\u65f6\u4e0d\u5b58\u5728\u4efb\u4f55\u7c7b\u578b\u76f8\u5173\u7684\u4fe1\u606f\u3002<\/p>\n
          \n
        • \n
          \u4ec0\u4e48\u662f\u6cdb\u578b\u4e2d\u7684\u9650\u5b9a\u901a\u914d\u7b26\u548c\u975e\u9650\u5b9a\u901a\u914d\u7b26 ?<\/section>\n<\/li>\n<\/ul>\n
          \u9650\u5b9a\u901a\u914d\u7b26\u5bf9\u7c7b\u578b\u8fdb\u884c\u4e86\u9650\u5236\u3002\u6709\u4e24\u79cd\u9650\u5b9a\u901a\u914d\u7b26\uff0c\u4e00\u79cd\u662f<? extends T><\/code>\u5b83\u901a\u8fc7\u786e\u4fdd\u7c7b\u578b\u5fc5\u987b\u662fT\u7684\u5b50\u7c7b\u6765\u8bbe\u5b9a\u7c7b\u578b\u7684\u4e0a\u754c\uff0c\u53e6\u4e00\u79cd\u662f<? super T><\/code>\u5b83\u901a\u8fc7\u786e\u4fdd\u7c7b\u578b\u5fc5\u987b\u662fT\u7684\u7236\u7c7b\u6765\u8bbe\u5b9a\u7c7b\u578b\u7684\u4e0b\u754c\u3002\u6cdb\u578b\u7c7b\u578b\u5fc5\u987b\u7528\u9650\u5b9a\u5185\u7684\u7c7b\u578b\u6765\u8fdb\u884c\u521d\u59cb\u5316\uff0c\u5426\u5219\u4f1a\u5bfc\u81f4\u7f16\u8bd1\u9519\u8bef\u3002\u53e6\u4e00\u65b9\u9762<?><\/code>\u8868\u793a\u4e86\u975e\u9650\u5b9a\u901a\u914d\u7b26\uff0c\u56e0\u4e3a<?><\/code>\u53ef\u4ee5\u7528\u4efb\u610f\u7c7b\u578b\u6765\u66ff\u4ee3\u3002<\/p>\n
            \n
          • \n
            List<? extends T><\/code>\u548cList <? super T><\/code>\u4e4b\u95f4\u6709\u4ec0\u4e48\u533a\u522b \u2753<\/section>\n<\/li>\n<\/ul>\n
            \u8fd9\u4e24\u4e2aList\u7684\u58f0\u660e\u90fd\u662f\u9650\u5b9a\u901a\u914d\u7b26\u7684\u4f8b\u5b50\uff0cList<? extends T><\/code>\u53ef\u4ee5\u63a5\u53d7\u4efb\u4f55\u7ee7\u627f\u81eaT\u7684\u7c7b\u578b\u7684List\uff0c\u800cList<? super T><\/code>\u53ef\u4ee5\u63a5\u53d7\u4efb\u4f55T\u7684\u7236\u7c7b\u6784\u6210\u7684List<\/code>\u3002\u4f8b\u5982List<? extends Number><\/code>\u53ef\u4ee5\u63a5\u53d7List<Integer><\/code>\u6216List<Float><\/code>\u3002<\/p>\n
              \n
            • \n
              \u5982\u4f55\u7f16\u5199\u4e00\u4e2a\u6cdb\u578b\u65b9\u6cd5\uff0c\u8ba9\u5b83\u80fd\u63a5\u53d7\u6cdb\u578b\u53c2\u6570\u5e76\u8fd4\u56de\u6cdb\u578b\u7c7b\u578b?<\/section>\n<\/li>\n<\/ul>\n
              \u7f16\u5199\u6cdb\u578b\u65b9\u6cd5\u5e76\u4e0d\u56f0\u96be\uff0c\u4f60\u9700\u8981\u7528\u6cdb\u578b\u7c7b\u578b\u6765\u66ff\u4ee3\u539f\u59cb\u7c7b\u578b\uff0c\u6bd4\u5982\u4f7f\u7528T, E or K,V<\/code>\u7b49\u88ab\u5e7f\u6cdb\u8ba4\u53ef\u7684\u7c7b\u578b\u5360\u4f4d\u7b26\u3002\u6700\u7b80\u5355\u7684\u60c5\u51b5\u4e0b\uff0c\u4e00\u4e2a\u6cdb\u578b\u65b9\u6cd5\u53ef\u80fd\u4f1a\u50cf\u8fd9\u6837:<\/p>\n
              <\/span>public<\/span> V put<\/span>(K key, V value)<\/span> <\/span>{
                  return<\/span> cache.put(key, value);
              }
              <\/code><\/pre>\n
                \n
              • \n
                \u7f16\u5199\u4e00\u6bb5\u6cdb\u578b\u7a0b\u5e8f\u6765\u5b9e\u73b0LRU\u7f13\u5b58?<\/section>\n<\/li>\n<\/ul>\n
                LinkedHashMap<\/code>\u53ef\u4ee5\u7528\u6765\u5b9e\u73b0\u56fa\u5b9a\u5927\u5c0f\u7684LRU\u7f13\u5b58\uff0c\u5f53LRU\u7f13\u5b58\u5df2\u7ecf\u6ee1\u4e86\u7684\u65f6\u5019\uff0c\u5b83\u4f1a\u628a\u6700\u8001\u7684\u952e\u503c\u5bf9\u79fb\u51fa\u7f13\u5b58\u3002LinkedHashMap\u63d0\u4f9b\u4e86\u4e00\u4e2a\u79f0\u4e3aremoveEldestEntry()<\/code>\u7684\u65b9\u6cd5\uff0c\u8be5\u65b9\u6cd5\u4f1a\u88abput()\u548cputAll()\u8c03\u7528\u6765\u5220\u9664\u6700\u8001\u7684\u952e\u503c\u5bf9\u3002<\/p>\n
                  \n
                • \n
                  \u4f60\u53ef\u4ee5\u628aList<String><\/code>\u4f20\u9012\u7ed9\u4e00\u4e2a\u63a5\u53d7List<Object><\/code>\u53c2\u6570\u7684\u65b9\u6cd5\u5417\uff1f<\/section>\n<\/li>\n<\/ul>\n
                  \u56e0\u4e3a\u4e4d\u770b\u8d77\u6765String<\/code>\u662f\u4e00\u79cdObject<\/code>\uff0c\u6240\u4ee5List<String><\/code>\u5e94\u5f53\u53ef\u4ee5\u7528\u5728\u9700\u8981 List<Object><\/code>\u7684\u5730\u65b9\uff0c\u4f46\u662f\u4e8b\u5b9e\u5e76\u975e\u5982\u6b64\u3002\u771f\u8fd9\u6837\u505a\u7684\u8bdd\u4f1a\u5bfc\u81f4\u7f16\u8bd1\u9519\u8bef\u3002\u5982\u679c\u4f60\u518d\u6df1\u4e00\u6b65\u8003\u8651\uff0c\u4f60\u4f1a\u53d1\u73b0Java\u8fd9\u6837\u505a\u662f\u6709\u610f\u4e49\u7684\uff0c\u56e0\u4e3aList<Object><\/code> \u53ef\u4ee5\u5b58\u50a8\u4efb\u4f55\u7c7b\u578b\u7684\u5bf9\u8c61\u5305\u62ecString, Integer<\/code>\u7b49\u7b49\uff0c\u800cList<String><\/code>\u5374\u53ea\u80fd\u7528\u6765\u5b58\u50a8String<\/code>\u3002<\/p>\n
                  <\/span>List<Object> objectList;
                  List<String> stringList;
                  objectList = stringList;  \/\/compilation error incompatible types<\/span>
                  <\/code><\/pre>\n
                    \n
                  • \n
                    Array<\/code>\u4e2d\u53ef\u4ee5\u7528\u6cdb\u578b\u5417?<\/section>\n<\/li>\n<\/ul>\n
                    \u524d\u63d0\u662f\u4f60\u8981\u77e5\u9053Array\u4e8b\u5b9e\u4e0a\u5e76\u4e0d\u652f\u6301\u6cdb\u578b\uff0c\u56e0\u4e3aList\u53ef\u4ee5\u63d0\u4f9b\u7f16\u8bd1\u671f\u7684\u7c7b\u578b\u5b89\u5168\u4fdd\u8bc1\uff0c\u800cArray\u5374\u4e0d\u80fd\u3002<\/p>\n
                    blog\u5730\u5740 \u83b7\u53d6\u66f4\u591a\u5185\u5bb9~<\/p>\n