{"id":388,"date":"2022-03-18T20:03:55","date_gmt":"2022-03-18T12:03:55","guid":{"rendered":"http:\/\/101.43.188.165\/?p=388"},"modified":"2022-03-18T20:03:56","modified_gmt":"2022-03-18T12:03:56","slug":"java%e5%9f%ba%e7%a1%80%ef%bc%8c%e5%a4%9a%e6%80%81","status":"publish","type":"post","link":"http:\/\/shuaihui.icu\/index.php\/2022\/03\/18\/java%e5%9f%ba%e7%a1%80%ef%bc%8c%e5%a4%9a%e6%80%81\/","title":{"rendered":"Java\u57fa\u7840\uff0c\u591a\u6001"},"content":{"rendered":"\n

\u591a\u6001\u7684\u6982\u8ff0<\/p>\n\n\n\n

\u540c\u4e00\u4e2a\u5bf9\u8c61\uff0c\u5728\u4e0d\u540c\u65f6\u523b\u8868\u73b0\u51fa\u6765\u7684\u4e0d\u540c\u5f62\u6001<\/p>\n\n\n\n

\u4e3e\u4f8b\uff1a<\/p>\n\n\n\n

\"\"<\/div><\/figure>\n\n\n\n

\u591a\u6001\u7684\u524d\u63d0\u548c\u4f53\u73b0<\/p>\n\n\n\n

1\u6709\u7ee7\u627f\/\u5b9e\u73b0\u5173\u7cfb<\/p>\n\n\n\n

2\u6709\u65b9\u6cd5\u91cd\u5199<\/p>\n\n\n\n

3\u6709\u7236\u7c7b\u5f15\u7528\u6307\u5411\u5b50\u7c7b\u5bf9\u8c61<\/p>\n\n\n\n

<\/p>\n\n\n\n

\u591a\u6001\u4e2d\u6210\u5458\u7684\u8bbf\u95ee\u7279\u70b9<\/p>\n\n\n\n

\u521b\u5efaAnimal\u7c7b<\/p>\n\n\n\n

public class Animal {\n    public int age = 40;\n    public void eat(){\n        System.out.println(\"\u52a8\u7269\u5403\u4e1c\u897f\");\n    }\n}<\/code><\/pre>\n\n\n\n
\u521b\u5efacat\u7c7b<\/p>\n\n\n\n
public class Cat extends Animal{\n    public int age = 20;\n    public int weight = 20;\n\n    @Override\n    public void eat() {\n        System.out.println(\"\u732b\u5403\u9c7c\");\n    }\n    public void playGame(){\n        System.out.println(\"\u8eb2\u732b\u732b\");\n    }\n}<\/code><\/pre>\n\n\n\n
\u521b\u5efaanimaldemo\u7c7b<\/p>\n\n\n\n
public class AnimalDemo {\n    public static void main(String[] args) {\n        \/\/\u7236\u7c7b\u5f15\u7528\u6307\u5411\u5b50\u7c7b\u5bf9\u8c61\n        Animal animal = new Cat();\n        System.out.println(animal.age);\n       \/\/ System.out.println(animal.weight);\n        animal.eat();\n        \/\/ \u62a5\u9519 animal.playGame();\n    }\n}<\/code><\/pre>\n\n\n\n
\u6267\u884c\u7ed3\u679c<\/p>\n\n\n\n
\"C:\\Program Files\\Java\\jdk1.8.0_131\\bin\\java.exe\" \"-javaagent:D:\\IntelliJ IDEA com.itheima_05.AnimalDemo\n40\n\u732b\u5403\u9c7c\n\n\u8fdb\u7a0b\u5df2\u7ed3\u675f,\u9000\u51fa\u4ee3\u78010<\/code><\/pre>\n\n\n\n
\u603b\u7ed3\uff1a\u6210\u5458\u53d8\u91cf\uff1a \u7f16\u8bd1\u770b\u5de6\u8fb9\uff0c\u6267\u884c\u770b\u53f3\u8fb9<\/p>\n\n\n\n
\u6210\u5458\u65b9\u6cd5\uff0c\u7f16\u8bd1\u770b\u5de6\u8fb9\uff0c\u6267\u884c\u770b\u53f3\u8fb9<\/p>\n\n\n\n
\u5176\u5b9e\u90fd\u53ef\u4ee5\u770b\u5de6\u8fb9\uff0c\u65b9\u6cd5\u6709\u91cd\u5199\u770b\u91cd\u5199<\/strong><\/p>\n\n\n\n
\u591a\u6001\u7684\u597d\u5904\u548c\u5f0a\u7aef<\/p>\n\n\n\n
\u597d\u5904\uff1a\u63d0\u9ad8\u4e86\u7a0b\u5e8f\u7684\u6269\u5c55\u6027<\/p>\n\n\n\n
\u5177\u4f53\u4f53\u73b0\uff1a\u5b9a\u4e49\u65b9\u6cd5\u7684\u65f6\u5019\uff0c\u4f7f\u7528\u7236\u7c7b\u578b\u4f5c\u4e3a\u53c2\u6570\uff0c\u5c06\u6765\u5728\u4f7f\u7528\u7684\u65f6\u5019\uff0c\u4f7f\u7528\u5177\u4f53\u7684\u5b50\u7c7b\u578b\u53c2\u4e0e\u64cd\u4f5c<\/p>\n\n\n\n
\u5f0a\u7aef\uff1a\u5982\u679c\u7236\u7c7b\u6ca1\u6709\u8be5\u65b9\u6cd5\uff0c\u5b50\u7c7b\u6ca1\u6709\u91cd\u5199\uff0c\u5219\u4e0d\u80fd\u4f7f\u7528\u5b50\u7c7b\u7684\u7279\u6709\u7684\u529f\u80fd<\/p>\n\n\n\n
\u591a\u6001\u4e2d\u7684\u8f6c\u578b\uff1a<\/p>\n\n\n\n
\u5411\u4e0a\u8f6c\u578b\uff1a<\/strong><\/p>\n\n\n\n
 \u4ece\u5b50\u5230\u7236<\/p>\n\n\n\n
\u7236\u7c7b\u5f15\u7528\u6307\u5411\u5b50\u7c7b\u5bf9\u8c61<\/p>\n\n\n\n
\u5411\u4e0b\u8f6c\u578b\uff1a<\/strong><\/p>\n\n\n\n
\u4ece\u7236\u5230\u5b50<\/p>\n\n\n\n
\u7236\u7c7b\u5f15\u7528\u8f6c\u4e3a\u5b50\u7c7b\u5bf9\u8c61<\/p>\n\n\n\n
\u521b\u5efaAnimal\u7c7b<\/p>\n\n\n\n
public class Animal {\n    public void eat(){\n        System.out.println(\"\u5403\u4e1c\u897f\");\n    }\n}<\/code><\/pre>\n\n\n\n
\u521b\u5efaCat\u7c7b<\/p>\n\n\n\n
public class Cat extends Animal{\n    @Override\n    public void eat() {\n        System.out.println(\"\u732b\u5403\u9c7c\");\n    }\n    public void playGame() {\n        System.out.println(\"\u73a9\u6e38\u620f\");\n    }\n}<\/code><\/pre>\n\n\n\n
\u521b\u5efaAnimalDemo\u7c7b<\/p>\n\n\n\n
public class AnimalDemo {\n    public static void main(String[] args) {\n        \/\/\u591a\u6001   \u5411\u4e0a\u8f6c\u578b\n        Animal animal = new Cat();\n\n\/\/        Cat cat = new Cat();\n\/\/        cat.eat();\n\/\/        cat.playGame();\n\n        \/\/\u5411\u4e0b\u8f6c\u578b\n        Cat cat1=(Cat) animal;  \/\/\u7236\u7c7b\u5bf9\u8c61\u5f3a\u5236\u8f6c\u6362\u6210\u5b50\u7c7b\u5bf9\u8c61   \u5c31\u662f\u5411\u4e0b\u8f6c\u578b\n        cat1.eat();\n        cat1.playGame();\n    }\n}\n<\/code><\/pre>\n\n\n\n
\u7279\u522b\u8bf4\u660e\uff1a<\/p>\n\n\n\n
Animal animal = new Cat();<\/p>\n\n\n\n
animal.eat\uff08\uff09\uff1b\u7f16\u8bd1\u53ef\u4ee5\u901a\u8fc7\u662f\u56e0\u4e3aanimal\u4e2d\u6709eat\u65b9\u6cd5\uff0c\u6267\u884c\u7684\u65f6\u5019\u5219\u662f\u770bCat\u4e2d\u88ab\u91cd\u5199\u8fc7\u7684eat\u65b9\u6cd5\uff1b<\/p>\n\n\n\n
 \u7f16\u8bd1\u770b\u5de6\u8fb9\uff0c\u6267\u884c\u770b\u53f3\u8fb9<\/p>\n\n\n\n
\u8fd9\u6837\u662f\u53ef\u4ee5\u901a\u8fc7animal\u6765\u8c03\u7528cat\u7684eat\u65b9\u6cd5\u4e86\uff0c\u4f46\u662f\u6211\u4eec\u8981\u4f7f\u7528cat\u7279\u6709\u7684\u65b9\u6cd5\u7684\u65f6\u5019\uff0c\u5c31\u8981\u518d\u521b\u5efa\u4e00\u4e2acat\u5bf9\u8c61\uff0c\u8fd9\u6837\u4e00\u6765\u5c31\u521b\u5efa\u4e86\u4e24\u4e2acat\u5bf9\u8c61\uff0c\u5f00\u8f9f\u4e86\u4e24\u6b21\u7a7a\u95f4\uff0c\u975e\u5e38\u6d6a\u8d39<\/p>\n\n\n\n
\u8fd9\u4e2a\u65f6\u5019\u6211\u4eec\u53ef\u4ee5\u4f7f\u7528\u5411\u4e0b\u8f6c\u578b\uff0c\u5728\u5411\u4e0a\u8f6c\u578b\u7684\u57fa\u7840\u4e4b\u4e0a\uff0c\u5c06animal\u5bf9\u8c61\u5f3a\u5236\u8f6c\u6362\u6210Cat\u5bf9\u8c61 <\/p>\n\n\n\n
\u5373Cat cat1=(Cat) animal<\/p>\n\n\n\n
\u8fd9\u6837\u5de6\u53f3\u4e24\u8fb9\u90fd\u662fCat\u7c7b\uff0c\u81ea\u7136\u53ef\u4ee5\u8c03\u7528Cat\u7279\u6709\u7684\u65b9\u6cd5\uff0cplay games\uff08\uff09\u3002<\/p>\n\n\n\n
\u4e00\u822c\u5b9e\u9645\u5de5\u4f5c\u4e2dperson\u90fd\u4f1a\u662f\u4e00\u4e2a\u63a5\u53e3\uff0c\u800c\u63a5\u53e3\u4e0d\u80fdnew\u5bf9\u8c61\uff0c\u5c31\u65e0\u6cd5\u8c03\u7528\u65b9\u6cd5\uff0c\u8fd9\u65f6\u5019\u5c31\u8981\u5411\u4e0a\u8f6c\u578b\uff0c\u518d\u8c03\u7528\u65b9\u6cd5\uff0c\u800c\u4e14\u53ea\u80fd\u8c03\u7528\u63a5\u53e3\u91cc\u7684\u65b9\u6cd5\uff0c\u800c\u4e0d\u80fd\u8c03\u7528\u5b9e\u73b0\u7c7b\u65b9\u6cd5\u3002<\/p>\n\n\n\n
\u5185\u5b58\u56fe\u8be6\u89e3<\/p>\n\n\n\n
1\u7a0b\u5e8f\u5f00\u59cb\uff0cmain\u65b9\u6cd5\u5148\u88ab\u52a0\u8f7d\u5230\u6808\u5185\u5b58\uff0c<\/p>\n\n\n\n
\u7136\u540eAnimal a \u88ab\u52a0\u8f7d\u5230main\u65b9\u6cd5\u4e2d\uff0c<\/p>\n\n\n\n
new Cat\u5728\u5806\u5185\u5b58\u4e2d\u5f00\u8f9f\u7a7a\u95f4\uff0c\u5730\u5740\u503c\u4e3a001\uff0c\u5e76\u628a\u5730\u5740\u503c\u7ed9Animal a<\/p>\n\n\n\n
\u5230\u8fd9\u91cc\u662f\u591a\u6001\u7684\u5f62\u5f0f\uff0c\u5411\u4e0a\u8f6c\u578b<\/p>\n\n\n\n
\"\"<\/div><\/figure>\n\n\n\n
\u5728\u591a\u6001\u4e2d\uff0c\u7f16\u8bd1\u770b\u5de6\u8fb9\uff0c\u6267\u884c\u770b\u53f3\u8fb9<\/p>\n\n\n\n
\u8fd9\u65f6\u5019\u5c31\u8981\u8c03\u7528Cat\u4e2d\u7684eat\u65b9\u6cd5\uff0c\u6240\u4ee5Cat\u7c7b\u548c\u65b9\u6cd5eat\u88ab\u52a0\u8f7d\u5230\u6808\u5185\u5b58\u4e2d<\/p>\n\n\n\n
\u65b9\u6cd5\u8c03\u7528\u5b8c\u6bd5\uff0cCat\u7c7b\u548ceat\u65b9\u6cd5\u6d88\u5931<\/p>\n\n\n\n
<\/p>\n\n\n\n
\"\"<\/div><\/figure>\n\n\n\n
Cat c \u88ab\u52a0\u8f7d\u5230main\u65b9\u6cd5\u4e2d<\/p>\n\n\n\n
\u56e0\u4e3a\u8fd9\u65f6a\u7684\u5730\u5740\u503c\u539f\u672c\u5c31\u662f001\uff0c\u6307\u5411\u5730\u5740\u503c\u4e3a001\u7684cat<\/p>\n\n\n\n
\u8fd9\u65f6\u6211\u4eec\u5427001 \u4e5f\u7ed9\u5230 Cat c <\/p>\n\n\n\n
\"\"<\/div><\/figure>\n\n\n\n
\u8fd9\u65f6\u8c03\u7528\u65b9\u6cd5\u5c31\u76f8\u5f53\u4e8e\u8c03\u7528001 Cat\u4e2d\u7684<\/p>\n\n\n\n
\"\"<\/div><\/figure>\n\n\n\n
\u8fd9\u65f6\u6211\u4eec\u5411\u4e0a\u8f6c\u578b\u72d7 dog \u4e24\u8005\u4e3a\u7ee7\u627f\u5173\u7cfb\uff0c\u6240\u4ee5\u6210\u7acb\uff0c\u5728\u5806\u5185\u5b58\u7a7a\u95f4\u4e2d\u521b\u5efa\u4e00\u4e2anew Dog\uff08\uff09 \u5730\u5740\u503c\u4e3a002\u7684\u7a7a\u95f4 \u540c\u65f6a\u7684\u5730\u5740\u503c\u53d8\u4e3a002<\/p>\n\n\n\n
\"\"<\/div><\/figure>\n\n\n\n
\u7f16\u8bd1\u770b\u5de6\u8fb9\uff0c\u6267\u884c\u770b\u53f3\u8fb9\uff0c\u53f3\u8fb9\u662fDog\uff0c\u6240\u4ee5\u53bbDog\u4e2d\u627eeat\u65b9\u6cd5\uff0c\u8f93\u51fa<\/p>\n\n\n\n
<\/p>\n\n\n\n
\"\"<\/div><\/figure>\n\n\n\n
\u8fd9\u65f6\u6211\u4eec\u518d\u5411\u4e0b\u8f6c\u578b\uff0c\u8fd9\u65f6\u5019a \u7684\u5730\u5740\u503c002 \u6307\u5411 \u72d7\uff0c\u5de6\u8fb9\u662f\u732b\uff0c\u53f3\u8fb9\u662f\u72d7\uff0c<\/p>\n\n\n\n
\"\"<\/div><\/figure>\n\n\n\n
\u867d\u7136\u732b\u72d7\u90fd\u7ee7\u627f\u81ea\u52a8\u7269\uff0c\u4f46\u662f\u5f7c\u6b64\u5e76\u4e0d\u76f8\u7b49\uff0c\u5982\u679c\u5f3a\u5236\u6267\u884c\uff0c\u5c31\u4f1a\u4ea7\u751fClassCastException\uff08\u7c7b\u578b\u8f6c\u6362\u5f02\u5e38\uff09<\/p>\n\n\n\n
\"\"<\/div><\/figure>\n","protected":false},"excerpt":{"rendered":"
\u591a\u6001\u7684\u6982\u8ff0 \u540c\u4e00\u4e2a\u5bf9\u8c61\uff0c\u5728\u4e0d\u540c\u65f6\u523b\u8868\u73b0\u51fa\u6765\u7684\u4e0d\u540c\u5f62\u6001 \u4e3e\u4f8b\uff1a \u591a\u6001\u7684\u524d\u63d0\u548c\u4f53\u73b0 1\u6709\u7ee7\u627f\/\u5b9e\u73b0\u5173\u7cfb 2\u6709\u65b9\u6cd5\u91cd […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":true,"template":"","format":"standard","meta":{"_uag_custom_page_level_css":"","footnotes":""},"categories":[5,29,20],"tags":[27,30,31],"class_list":["post-388","post","type-post","status-publish","format-standard","hentry","category-java","category-29","category-20","tag-java","tag-30","tag-31"],"uagb_featured_image_src":{"full":false,"thumbnail":false,"medium":false,"medium_large":false,"large":false,"1536x1536":false,"2048x2048":false},"uagb_author_info":{"display_name":"xiaofeng","author_link":"http:\/\/shuaihui.icu\/index.php\/author\/xiaofeng\/"},"uagb_comment_info":0,"uagb_excerpt":"\u591a\u6001\u7684\u6982\u8ff0 \u540c\u4e00\u4e2a\u5bf9\u8c61\uff0c\u5728\u4e0d\u540c\u65f6\u523b\u8868\u73b0\u51fa\u6765\u7684\u4e0d\u540c\u5f62\u6001 \u4e3e\u4f8b\uff1a \u591a\u6001\u7684\u524d\u63d0\u548c\u4f53\u73b0 1\u6709\u7ee7\u627f\/\u5b9e\u73b0\u5173\u7cfb 2\u6709\u65b9\u6cd5\u91cd…","_links":{"self":[{"href":"http:\/\/shuaihui.icu\/index.php\/wp-json\/wp\/v2\/posts\/388","targetHints":{"allow":["GET"]}}],"collection":[{"href":"http:\/\/shuaihui.icu\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"http:\/\/shuaihui.icu\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"http:\/\/shuaihui.icu\/index.php\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"http:\/\/shuaihui.icu\/index.php\/wp-json\/wp\/v2\/comments?post=388"}],"version-history":[{"count":7,"href":"http:\/\/shuaihui.icu\/index.php\/wp-json\/wp\/v2\/posts\/388\/revisions"}],"predecessor-version":[{"id":409,"href":"http:\/\/shuaihui.icu\/index.php\/wp-json\/wp\/v2\/posts\/388\/revisions\/409"}],"wp:attachment":[{"href":"http:\/\/shuaihui.icu\/index.php\/wp-json\/wp\/v2\/media?parent=388"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"http:\/\/shuaihui.icu\/index.php\/wp-json\/wp\/v2\/categories?post=388"},{"taxonomy":"post_tag","embeddable":true,"href":"http:\/\/shuaihui.icu\/index.php\/wp-json\/wp\/v2\/tags?post=388"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}