{"id":31107,"date":"2023-05-06T17:52:38","date_gmt":"2023-05-04T03:26:04","guid":{"rendered":"https:\/\/www.silicloud.com\/zh\/blog\/%e5%85%b3%e4%ba%8ejava%e7%9a%84%e9%80%9a%e9%85%8d%e7%ac%a6%e8%be%b9%e7%95%8c%e3%80%82\/"},"modified":"2025-08-12T22:21:38","modified_gmt":"2025-08-12T14:21:38","slug":"%e5%85%b3%e4%ba%8ejava%e7%9a%84%e9%80%9a%e9%85%8d%e7%ac%a6%e8%be%b9%e7%95%8c%e3%80%82","status":"publish","type":"post","link":"https:\/\/www.silicloud.com\/zh\/blog\/%e5%85%b3%e4%ba%8ejava%e7%9a%84%e9%80%9a%e9%85%8d%e7%ac%a6%e8%be%b9%e7%95%8c%e3%80%82\/","title":{"rendered":"\u5173\u4e8eJava\u7684\u901a\u914d\u7b26\u8fb9\u754c"},"content":{"rendered":"

\u9996\u5148<\/h2>\n

\u5173\u4e8eJava\u7684\u901a\u914d\u7b26\u754c\u9650\uff0c\u603b\u7ed3\u5982\u4e0b\u3002
\n\u4e3b\u8981\u6709\u4e09\u79cd\u5f62\u5f0f:
\n– \u65e0\u754c\u901a\u914d\u7b26
\n– \u4e0a\u754c\u901a\u914d\u7b26
\n– \u4e0b\u754c\u901a\u914d\u7b26<\/p>\n

\u975e\u754c\u5883\u7684\u91ce\u724c<\/h2>\n

\u4f7f\u7528\u901a\u914d\u7b26”?”\u53ef\u4ee5\u5728\u6cdb\u578b\u58f0\u660e\u65f6\uff0c\u4ee5\u4e0d\u9650\u5236\u7c7b\u578b\u53c2\u6570\u7684\u65b9\u5f0f\u5904\u7406\u7c7b\u3002\u5b83\u4e3b\u8981\u5177\u6709\u4e24\u4e2a\u7279\u70b9\uff1a
\n– \u65b9\u6cd5\u7684\u8fd4\u56de\u7c7b\u578b\u5c06\u662fObject\u7c7b\u578b\u3002
\n– \u65b9\u6cd5\u7684\u53c2\u6570\u53ea\u80fd\u4f20\u9012null\u5b57\u9762\u503c\u3002<\/p>\n

public<\/span> class<\/span> Main<\/span> {<\/span>\r\n    public<\/span> static<\/span> void<\/span> main<\/span>(<\/span>String<\/span>[]<\/span> args<\/span>)<\/span> throws<\/span> Exception<\/span> {<\/span>\r\n        \/\/ \u975e\u5883\u754c\u30ef\u30a4\u30eb\u30c9\u30ab\u30fc\u30c9\u3092\u4f7f\u7528\u3057\u30ea\u30b9\u30c8\u3092\u5ba3\u8a00<\/span>\r\n        ArrayList<\/span><?><\/span> list<\/span> =<\/span> new<\/span> ArrayList<\/span><>();<\/span>\r\n\r\n        ArrayList<\/span><<\/span>String<\/span>><\/span> strList<\/span> =<\/span> new<\/span> ArrayList<\/span><>();<\/span>\r\n\r\n        ArrayList<\/span><<\/span>Integer<\/span>><\/span> intList<\/span> =<\/span> new<\/span> ArrayList<\/span><>();<\/span>\r\n        \r\n        list<\/span>.<\/span>containsAll<\/span>(<\/span>strList<\/span>);<\/span>\r\n        list<\/span>.<\/span>containsAll<\/span>(<\/span>intList<\/span>);<\/span>\r\n    }<\/span>\r\n}<\/span>\r\n<\/code><\/pre>\n
\u4e0a\u9650\u5883\u754c\u7684\u4e07\u91d1\u6cb9<\/h2>\n
\u6cdb\u578b\u58f0\u660e\u65f6\u4f7f\u7528”extends”\uff0c\u9650\u5236\u53ef\u4ee5\u7528\u4f5c\u7c7b\u578b\u53c2\u6570\u7684\u7c7b\u7684\u8303\u56f4\u3002\u5bf9\u4e8e”<? extends T>”\uff0c\u53ea\u80fd\u5904\u7406T\u6216T\u7684\u5b50\u7c7b\u7c7b\u578b\u3002
\n– \u65b9\u6cd5\u7684\u8fd4\u56de\u503c\u53ef\u4ee5\u662f\u4efb\u4f55\u7c7b\u578b\u3002
\n– \u65b9\u6cd5\u7684\u53c2\u6570\u53ea\u80fd\u4f20\u9012\u7a7a\u503c\u5b57\u9762\u91cf\u3002<\/p>\n
public<\/span> class<\/span> Main<\/span> {<\/span>\r\n    public<\/span> static<\/span> void<\/span> main<\/span>(<\/span>String<\/span>[]<\/span> args<\/span>)<\/span> throws<\/span> Exception<\/span> {<\/span>\r\n        \r\n        ArrayList<\/span><<\/span>Integer<\/span>><\/span> intList<\/span> =<\/span> new<\/span> ArrayList<\/span><>();<\/span>\r\n        \r\n        ArrayList<\/span><<\/span>String<\/span>><\/span> strList<\/span> =<\/span> new<\/span> ArrayList<\/span><>();<\/span>\r\n\r\n        \/\/ Integer\u306fNumber\u306e\u30b5\u30d6\u30af\u30e9\u30b9\u306e\u305f\u3081\u547c\u3073\u51fa\u3059\u3053\u3068\u304c\u3067\u304d\u308b<\/span>\r\n        testList<\/span>(<\/span>intList<\/span>);<\/span>\r\n        \/\/ String\u306fNumber\u306e\u30b5\u30d6\u30af\u30e9\u30b9\u3067\u306f\u306a\u3044\u305f\u3081\u30b3\u30f3\u30d1\u30a4\u30eb\u30a8\u30e9\u30fc<\/span>\r\n        testList<\/span>(<\/span>strList<\/span>);<\/span>\r\n    }<\/span>\r\n\r\n    \/\/ \u4e0a\u9650\u5883\u754c\u30ef\u30a4\u30eb\u30c9\u30ab\u30fc\u30c9\u3092\u4f7f\u7528\u3057\u305f\u30e1\u30bd\u30c3\u30c9    <\/span>\r\n    public<\/span> static<\/span> void<\/span> testList<\/span>(<\/span>List<\/span><?<\/span> extends<\/span> Number<\/span>><\/span> list<\/span>)<\/span> {<\/span>\r\n        \/\/ list\u306b\u95a2\u3059\u308b\u51e6\u7406<\/span>\r\n    }<\/span>\r\n}<\/span>\r\n<\/code><\/pre>\n
\u4e0b\u9650\u5883\u754c\u662f\u4e00\u4e2a\u91ce\u5361\u3002<\/h2>\n
“super” is used in generics declarations, such as <? super T>, to restrict the range of classes that can be used as type parameters.
\nIn the case of <? super T>, only the type T or its superclass type can be handled.
\n-The return type of the method becomes Object type.
\n-Any type can be passed as an argument to the method.<\/p>\n
public<\/span> class<\/span> Main<\/span> {<\/span>\r\n    public<\/span> static<\/span> void<\/span> main<\/span>(<\/span>String<\/span>[]<\/span> args<\/span>)<\/span> throws<\/span> Exception<\/span> {<\/span>\r\n        \r\n        ArrayList<\/span><<\/span>Number<\/span>><\/span> numList<\/span> =<\/span> new<\/span> ArrayList<\/span><>();<\/span>\r\n        \r\n        ArrayList<\/span><<\/span>String<\/span>><\/span> strList<\/span> =<\/span> new<\/span> ArrayList<\/span><>();<\/span>\r\n\r\n        \/\/ Number\u306fInteger\u306e\u30b9\u30fc\u30d1\u30fc\u30af\u30e9\u30b9\u306e\u305f\u3081\u547c\u3073\u51fa\u3059\u3053\u3068\u304c\u3067\u304d\u308b<\/span>\r\n        testList<\/span>(<\/span>numList<\/span>);<\/span>\r\n        \/\/ String\u306fInteger\u306e\u30b9\u30fc\u30d1\u30fc\u30af\u30e9\u30b9\u3067\u306f\u306a\u3044\u305f\u3081\u30b3\u30f3\u30d1\u30a4\u30eb\u30a8\u30e9\u30fc<\/span>\r\n        testList<\/span>(<\/span>strList<\/span>);<\/span>\r\n    }<\/span>\r\n\r\n    \/\/ \u4e0b\u9650\u5883\u754c\u30ef\u30a4\u30eb\u30c9\u30ab\u30fc\u30c9\u3092\u4f7f\u7528\u3057\u305f\u30e1\u30bd\u30c3\u30c9    <\/span>\r\n    public<\/span> static<\/span> void<\/span> testList<\/span>(<\/span>List<\/span><?<\/span> super<\/span> Integer<\/span>><\/span> list<\/span>)<\/span> {<\/span>\r\n        \/\/ list\u306b\u95a2\u3059\u308b\u51e6\u7406<\/span>\r\n    }<\/span>\r\n}<\/span>\r\n<\/code><\/pre>\n","protected":false},"excerpt":{"rendered":"
\u9996\u5148 \u5173\u4e8eJava\u7684\u901a\u914d\u7b26\u754c\u9650\uff0c\u603b\u7ed3\u5982\u4e0b\u3002 \u4e3b\u8981\u6709\u4e09\u79cd\u5f62\u5f0f: – \u65e0\u754c\u901a\u914d\u7b26 – \u4e0a\u754c […]<\/p>\n","protected":false},"author":11,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1],"tags":[227],"class_list":["post-31107","post","type-post","status-publish","format-standard","hentry","category-uncategorized","tag-227"],"yoast_head":"\n\u5173\u4e8eJava\u7684\u901a\u914d\u7b26\u8fb9\u754c - Blog - Silicon Cloud<\/title>\n<meta name=\"description\" content=\"\u5173\u4e8e\u5173\u4e8eJava\u7684\u901a\u914d\u7b26\u8fb9\u754c\u7684\u6280\u672f\u6587\u7ae0\" \/>\n<meta name=\"robots\" content=\"index, follow, max-snippet:-1, max-image-preview:large, max-video-preview:-1\" \/>\n<link rel=\"canonical\" href=\"https:\/\/www.silicloud.com\/zh\/blog\/\u5173\u4e8ejava\u7684\u901a\u914d\u7b26\u8fb9\u754c\u3002\/\" \/>\n<meta property=\"og:locale\" content=\"zh_CN\" \/>\n<meta property=\"og:type\" content=\"article\" \/>\n<meta property=\"og:title\" content=\"\u5173\u4e8eJava\u7684\u901a\u914d\u7b26\u8fb9\u754c\" \/>\n<meta property=\"og:description\" content=\"\u5173\u4e8e\u5173\u4e8eJava\u7684\u901a\u914d\u7b26\u8fb9\u754c\u7684\u6280\u672f\u6587\u7ae0\" \/>\n<meta property=\"og:url\" content=\"https:\/\/www.silicloud.com\/zh\/blog\/\u5173\u4e8ejava\u7684\u901a\u914d\u7b26\u8fb9\u754c\u3002\/\" \/>\n<meta property=\"og:site_name\" content=\"Blog - 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