{"id":73002,"date":"2024-02-21T15:17:59","date_gmt":"2024-02-21T07:17:59","guid":{"rendered":"https:\/\/docs.pingcode.com\/?p=73002"},"modified":"2024-02-21T15:18:15","modified_gmt":"2024-02-21T07:18:15","slug":"java-%e4%b8%ad%e7%9a%84%e7%b1%bb%e5%9e%8b%e6%8e%a8%e6%96%ad%e6%98%af%e5%a6%82%e4%bd%95%e5%b7%a5%e4%bd%9c%e7%9a%84%ef%bc%9f-3","status":"publish","type":"post","link":"https:\/\/docs.pingcode.com\/ask\/73002.html","title":{"rendered":"Java \u4e2d\u7684\u7c7b\u578b\u63a8\u65ad\u662f\u5982\u4f55\u5de5\u4f5c\u7684\uff1f"},"content":{"rendered":"

\"Java<\/p>\n

\u5728Java\u4e2d\uff0c\u7c7b\u578b\u63a8\u65ad<\/strong>\u662f\u7f16\u8bd1\u65f6\u8fdb\u884c\u7684\u8fc7\u7a0b\uff0c\u5b83\u53ef\u4ee5\u81ea\u52a8\u63a8\u5bfc\u51fa\u8868\u8fbe\u5f0f\u7684\u7c7b\u578b\u3001\u51cf\u5c11\u4ee3\u7801\u5197\u4f59\u53ca\u589e\u5f3a\u53ef\u8bfb\u6027\u3002Java\u7684\u7c7b\u578b\u63a8\u65ad\u901a\u8fc7\u4ee5\u4e0b\u65b9\u5f0f\u5de5\u4f5c\uff1a\u81ea\u52a8\u63a8\u5bfc\u6cdb\u578b\u53c2\u6570\u7c7b\u578b\u3001\u7701\u7565\u5197\u4f59\u7c7b\u578b\u4fe1\u606f\u3001\u7b80\u5316Lambda\u8868\u8fbe\u5f0f\u7684\u7f16\u5199<\/strong>\u3002\u7279\u522b\u662f\u5728Java 8\u53ca\u4ee5\u540e\u7684\u7248\u672c\u4e2d\uff0c\u7c7b\u578b\u63a8\u65ad\u7684\u7279\u6027\u5f97\u5230\u4e86\u6781\u5927\u52a0\u5f3a\u3002\u5355\u72ec\u5c55\u5f00\u63cf\u8ff0\uff0c\u81ea\u52a8\u63a8\u5bfc\u6cdb\u578b\u53c2\u6570\u7c7b\u578b<\/strong>\u80fd\u591f\u4f7f\u5f97\u7f16\u7a0b\u4eba\u5458\u5728\u4f7f\u7528\u6cdb\u578b\u65f6\u4e0d\u5fc5\u660e\u786e\u6307\u5b9a\u6cdb\u578b\u7684\u5177\u4f53\u7c7b\u578b\u3002\u4f8b\u5982\uff0c\u5728\u4f7f\u7528\u96c6\u5408\u65f6\uff0c\u6211\u4eec\u4e4b\u524d\u53ef\u80fd\u9700\u8981\u8fd9\u6837\u5199`List list = new ArrayList();`\uff0c\u4f46\u73b0\u5728\u6211\u4eec\u53ef\u4ee5\u7b80\u5355\u5730\u5199\u6210`List list = new ArrayList<>();`\uff0c\u7f16\u8bd1\u5668\u4fbf\u80fd\u6839\u636e\u53d8\u91cf\u7684\u58f0\u660e\u63a8\u65ad\u51fa\u5b9e\u4f8b\u5316\u5bf9\u8c61\u7684\u5177\u4f53\u6cdb\u578b\u7c7b\u578b\u3002<\/p>\n

\u63a5\u4e0b\u6765\uff0c\u6211\u4eec\u5c06\u901a\u8fc7\u5177\u4f53\u7684\u5c0f\u6807\u9898\u6df1\u5165\u4e86\u89e3Java\u4e2d\u7684\u7c7b\u578b\u63a8\u65ad\u3002<\/p>\n

\u4e00\u3001\u6cdb\u578b\u7684\u7c7b\u578b\u63a8\u65ad<\/strong><\/p>\n

\u6cdb\u578b\u7684\u51fa\u73b0\u662f\u4e3a\u4e86\u5728\u7f16\u8bd1\u671f\u95f4\u63d0\u4f9b\u7c7b\u578b\u68c0\u67e5\uff0c\u5e76\u907f\u514d\u8fd0\u884c\u65f6\u7c7b\u578b\u9519\u8bef\u3002\u7c7b\u578b\u63a8\u65ad\u5728\u8fd9\u91cc\u53d1\u6325\u4e86\u91cd\u8981\u4f5c\u7528\u3002<\/p>\n

– \u5728\u96c6\u5408\u7c7b\u4e2d\u7684\u5e94\u7528<\/strong><\/p>\n

\u4e4b\u524d\u5728Java 7\u4e4b\u524d\uff0c\u6cdb\u578b\u5b9e\u4f8b\u5316\u7684\u65f6\u5019\u9700\u8981\u91cd\u590d\u58f0\u660e\u7c7b\u578b\uff0c\u5982`Map> myMap = new HashMap>();`\u3002\u4eceJava 7\u5f00\u59cb\uff0c\u5f15\u5165\u4e86\u201c\u83f1\u5f62\u201d\u8bed\u6cd5\uff08Diamond Operator\uff09\uff0c\u5373\u53ea\u9700\u8981\u5728\u5de6\u8fb9\u58f0\u660e\u7c7b\u578b\uff0c\u53f3\u8fb9\u53ef\u4ee5\u4f7f\u7528`<>`\u7701\u7565\u5177\u4f53\u7684\u7c7b\u578b\u4fe1\u606f\uff0c\u5982`Map> myMap = new HashMap<>();`\u3002\u8fd9\u6837\u7684\u7c7b\u578b\u63a8\u65ad\u7b80\u5316\u4e86\u4ee3\u7801\u7f16\u5199\uff0c\u8ba9\u7a0b\u5e8f\u66f4\u52a0\u7b80\u6d01\u3002<\/p>\n

– \u65b9\u6cd5\u8fd4\u56de\u7c7b\u578b\u7684\u63a8\u65ad<\/strong><\/p>\n

\u5728\u6cdb\u578b\u65b9\u6cd5\u4e2d\uff0c\u7f16\u8bd1\u5668\u4e5f\u80fd\u591f\u6839\u636e\u65b9\u6cd5\u7684\u8fd4\u56de\u7c7b\u578b\u63a8\u65ad\u6cdb\u578b\u53c2\u6570\u3002\u4f8b\u5982\uff0c`public static T pick(T a1, T a2) { return a2; }`\u65b9\u6cd5\u8c03\u7528\u65f6\uff0c\u4e0d\u9700\u8981\u6307\u5b9aT\u7684\u7c7b\u578b\uff0c\u7f16\u8bd1\u5668\u53ef\u4ee5\u6839\u636e\u4f20\u5165\u53c2\u6570\u6216\u8005\u4f7f\u7528\u4e0a\u4e0b\u6587\u63a8\u65ad\u51faT\u7684\u5b9e\u9645\u7c7b\u578b\u3002<\/p>\n

\u4e8c\u3001Lambda\u8868\u8fbe\u5f0f\u4e2d\u7684\u7c7b\u578b\u63a8\u65ad<\/strong><\/p>\n

Java 8\u5f15\u5165\u7684Lambda\u8868\u8fbe\u5f0f\uff0c\u4e5f\u662f\u7c7b\u578b\u63a8\u65ad\u5c55\u73b0\u5f97\u6dcb\u6f13\u5c3d\u81f4\u7684\u5730\u65b9\u3002<\/p>\n

– \u53c2\u6570\u7684\u7c7b\u578b\u63a8\u65ad<\/strong><\/p>\n

Lambda\u8868\u8fbe\u5f0f\u5141\u8bb8\u7701\u7565\u53c2\u6570\u7c7b\u578b\uff0c\u5982`(a, b) -> a + b`\u800c\u4e0d\u9700\u8981`(int a, int b) -> a + b`\uff0c\u7f16\u8bd1\u5668\u4f1a\u6839\u636e\u4e0a\u4e0b\u6587\u73af\u5883\u63a8\u65ad\u53c2\u6570\u7684\u7c7b\u578b\u3002<\/p>\n

– \u51fd\u6570\u63a5\u53e3\u7684\u7c7b\u578b\u4e0a\u4e0b\u6587\u63a8\u65ad<\/strong><\/p>\n

\u5f53Lambda\u8868\u8fbe\u5f0f\u88ab\u7528\u4f5c\u51fd\u6570\u5f0f\u63a5\u53e3\u7684\u5b9e\u73b0\u65f6\uff0c\u5b83\u7684\u53c2\u6570\u7c7b\u578b\u4f1a\u6839\u636e\u63a5\u53e3\u7684\u62bd\u8c61\u65b9\u6cd5\u5b9a\u4e49\u6765\u63a8\u65ad\u3002\u8fd9\u6837\u5f00\u53d1\u8005\u5c31\u4e0d\u5fc5\u5728\u6bcf\u4e2aLambda\u8868\u8fbe\u5f0f\u4e2d\u663e\u5f0f\u5730\u58f0\u660e\u7c7b\u578b\u3002<\/p>\n

\u4e09\u3001\u7c7b\u578b\u63a8\u65ad\u4e0e\u65b9\u6cd5\u91cd\u8f7d<\/strong><\/p>\n

\u5728Java\u4e2d\uff0c\u65b9\u6cd5\u91cd\u8f7d\u89e3\u6790\uff08Overload Resolution\uff09\u5728\u67d0\u4e9b\u60c5\u51b5\u4e0b\u4e5f\u6d89\u53ca\u5230\u7c7b\u578b\u63a8\u65ad\u3002<\/p>\n

– \u91cd\u8f7d\u89e3\u6790\u8fc7\u7a0b\u4e2d\u7684\u7c7b\u578b\u63a8\u65ad<\/strong><\/p>\n

\u8fdb\u884c\u65b9\u6cd5\u91cd\u8f7d\u65f6\uff0c\u7f16\u8bd1\u5668\u9700\u8981\u6839\u636e\u53c2\u6570\u7c7b\u578b\u786e\u5b9a\u8c03\u7528\u54ea\u4e2a\u65b9\u6cd5\u3002\u5982\u679c\u53c2\u6570\u662f\u6cdb\u578b\u7c7b\u578b\uff0c\u7f16\u8bd1\u5668\u4f1a\u5229\u7528\u7c7b\u578b\u63a8\u65ad\u6765\u786e\u5b9a\u6700\u5408\u9002\u7684\u65b9\u6cd5\u3002<\/p>\n

– \u9650\u5236\u4e0e\u6311\u6218<\/strong><\/p>\n

\u9700\u8981\u6ce8\u610f\u7684\u662f\uff0c\u5982\u679c\u4e00\u4e2a\u7c7b\u4e2d\u5b9a\u4e49\u4e86\u591a\u4e2a\u53ea\u5728\u8fd4\u56de\u7c7b\u578b\u4e0a\u6709\u5dee\u5f02\u7684\u91cd\u8f7d\u65b9\u6cd5\uff0c\u7c7b\u578b\u63a8\u65ad\u53ef\u80fd\u65e0\u6cd5\u6b63\u5e38\u5e94\u7528\u3002\u56e0\u4e3aJava\u7684\u7c7b\u578b\u63a8\u65ad\u673a\u5236\u4e3b\u8981\u4f9d\u8d56\u53c2\u6570\u7c7b\u578b\uff0c\u800c\u4e0d\u662f\u8fd4\u56de\u7c7b\u578b\u3002<\/p>\n

\u56db\u3001\u5c40\u9650\u6027\u4e0e\u89e3\u51b3\u65b9\u5f0f<\/strong><\/p>\n

\u5c3d\u7ba1\u7c7b\u578b\u63a8\u65ad\u5728Java\u4e2d\u63d0\u4f9b\u4e86\u5f88\u591a\u4fbf\u5229\u548c\u4ee3\u7801\u7b80\u6d01\u6027\uff0c\u4f46\u5b83\u4e5f\u6709\u81ea\u5df1\u7684\u5c40\u9650\u3002<\/p>\n

– \u5c40\u9650\u6027<\/strong><\/p>\n

\u67d0\u4e9b\u590d\u6742\u7684\u7f16\u7a0b\u573a\u666f\u4e2d\uff0c\u7f16\u8bd1\u5668\u53ef\u80fd\u65e0\u6cd5\u6210\u529f\u63a8\u65ad\u51fa\u6b63\u786e\u7684\u7c7b\u578b\uff0c\u6216\u8005\u53ef\u80fd\u5bfc\u81f4\u7c7b\u578b\u63a8\u65ad\u7684\u7ed3\u679c\u4e0e\u9884\u671f\u4e0d\u4e00\u81f4\u3002<\/p>\n

– \u663e\u793a\u7c7b\u578b\u58f0\u660e\u7684\u5fc5\u8981\u6027<\/strong><\/p>\n

\u5f53\u7c7b\u578b\u63a8\u65ad\u65e0\u6cd5\u6839\u636e\u4e0a\u4e0b\u6587\u6b63\u786e\u63a8\u65ad\u51fa\u7c7b\u578b\u65f6\uff0c\u5f00\u53d1\u8005\u53ef\u80fd\u9700\u8981\u663e\u793a\u5730\u58f0\u660e\u7c7b\u578b\u4fe1\u606f\u4ee5\u63d0\u4f9b\u7ed9\u7f16\u8bd1\u5668\u8fdb\u884c\u6b63\u786e\u7684\u63a8\u65ad\u3002\u6bd5\u7adf\uff0c\u7c7b\u578b\u63a8\u65ad\u80fd\u529b\u7684\u589e\u5f3a\uff0c\u5e76\u4e0d\u610f\u5473\u7740\u5b8c\u5168\u4e0d\u9700\u8981\u7c7b\u578b\u58f0\u660e\uff0c\u5408\u7406\u5229\u7528\u663e\u793a\u7c7b\u578b\u58f0\u660e\u4ecd\u7136\u662f\u5fc5\u8981\u7684\u3002<\/p>\n

\u901a\u8fc7\u4ee5\u4e0a\u7684\u89e3\u6790\uff0c\u6211\u4eec\u53ef\u4ee5\u770b\u5230Java\u4e2d\u7684\u7c7b\u578b\u63a8\u65ad\u5927\u5927\u63d0\u9ad8\u4e86\u4ee3\u7801\u7684\u7b80\u6d01\u6027\u548c\u5f00\u53d1\u6548\u7387\uff0c\u540c\u65f6\u7f16\u7a0b\u8005\u4e5f\u9700\u8981\u4e86\u89e3\u5176\u80cc\u540e\u7684\u5de5\u4f5c\u673a\u5236\u53ca\u5176\u9002\u7528\u8303\u56f4\u4ee5\u4fbf\u66f4\u5408\u7406\u5730\u7f16\u5199\u4ee3\u7801\u3002<\/p>\n

\u76f8\u5173\u95ee\u7b54FAQs\uff1a<\/strong><\/h2>\n

\u4ec0\u4e48\u662f Java \u7c7b\u578b\u63a8\u65ad\uff1f<\/strong><\/p>\n

Java \u7c7b\u578b\u63a8\u65ad\u662f\u6307\u7f16\u8bd1\u5668\u5728\u7f16\u8bd1\u65f6\u6839\u636e\u4e0a\u4e0b\u6587\u4fe1\u606f\u81ea\u52a8\u63a8\u65ad\u51fa\u8868\u8fbe\u5f0f\u4e2d\u7684\u6570\u636e\u7c7b\u578b\uff0c\u800c\u65e0\u9700\u663e\u5f0f\u5730\u6307\u5b9a\u7c7b\u578b\u3002\u8fd9\u79cd\u529f\u80fd\u53ef\u4ee5\u51cf\u5c11\u4ee3\u7801\u5197\u4f59\uff0c\u63d0\u9ad8\u4ee3\u7801\u7684\u53ef\u8bfb\u6027\u548c\u53ef\u7ef4\u62a4\u6027\u3002<\/p>\n

Java \u7c7b\u578b\u63a8\u65ad\u7684\u5de5\u4f5c\u539f\u7406\u662f\u4ec0\u4e48\uff1f<\/strong><\/p>\n

\u5728 Java 7 \u4e2d\u5f15\u5165\u7684\u83f1\u5f62\u64cd\u4f5c\u7b26`<>`\u4f7f\u5f97\u7f16\u8bd1\u5668\u80fd\u591f\u6839\u636e\u53d8\u91cf\u7684\u58f0\u660e\u7c7b\u578b\u6765\u81ea\u52a8\u63a8\u65ad\u6cdb\u578b\u7c7b\u578b\uff0c\u4f8b\u5982`List list = new ArrayList<>()`\u3002Java 10 \u4e2d\u5f15\u5165\u7684\u5c40\u90e8\u53d8\u91cf\u7c7b\u578b\u63a8\u65ad(var)\u66f4\u8fdb\u4e00\u6b65\uff0c\u53ef\u4ee5\u5728\u5c40\u90e8\u53d8\u91cf\u58f0\u660e\u65f6\u81ea\u52a8\u63a8\u65ad\u53d8\u91cf\u7684\u6570\u636e\u7c7b\u578b\uff0c\u4f8b\u5982`var list = new ArrayList()`\u3002<\/p>\n

\u7c7b\u578b\u63a8\u65ad\u7684\u597d\u5904\u662f\u4ec0\u4e48\uff1f<\/strong><\/p>\n

\u7c7b\u578b\u63a8\u65ad\u53ef\u4ee5\u8ba9\u4ee3\u7801\u66f4\u52a0\u7b80\u6d01\uff0c\u51cf\u5c11\u6837\u677f\u4ee3\u7801\u7684\u7f16\u5199\uff0c\u63d0\u9ad8\u5f00\u53d1\u6548\u7387\u3002\u540c\u65f6\uff0c\u4f7f\u7528\u7c7b\u578b\u63a8\u65ad\u8fd8\u53ef\u4ee5\u51cf\u5c11\u7c7b\u578b\u9519\u8bef\u7684\u53ef\u80fd\u6027\uff0c\u907f\u514d\u56e0\u4e3a\u624b\u52a8\u6307\u5b9a\u7c7b\u578b\u800c\u5bfc\u81f4\u7684\u4ee3\u7801\u7ef4\u62a4\u96be\u5ea6\u589e\u52a0\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"\u5728Java\u4e2d\uff0c\u7c7b\u578b\u63a8\u65ad\u662f\u7f16\u8bd1\u65f6\u8fdb\u884c\u7684\u8fc7\u7a0b\uff0c\u5b83\u53ef\u4ee5\u81ea\u52a8\u63a8\u5bfc\u51fa\u8868\u8fbe\u5f0f\u7684\u7c7b\u578b\u3001\u51cf\u5c11\u4ee3\u7801\u5197\u4f59\u53ca\u589e\u5f3a\u53ef\u8bfb\u6027\u3002Java\u7684\u7c7b […]","protected":false},"author":1,"featured_media":73005,"comment_status":"closed","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"footnotes":""},"categories":[37],"tags":[],"acf":[],"_links":{"self":[{"href":"https:\/\/docs.pingcode.com\/wp-json\/wp\/v2\/posts\/73002"}],"collection":[{"href":"https:\/\/docs.pingcode.com\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/docs.pingcode.com\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/docs.pingcode.com\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/docs.pingcode.com\/wp-json\/wp\/v2\/comments?post=73002"}],"version-history":[{"count":0,"href":"https:\/\/docs.pingcode.com\/wp-json\/wp\/v2\/posts\/73002\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/docs.pingcode.com\/wp-json\/wp\/v2\/media\/73005"}],"wp:attachment":[{"href":"https:\/\/docs.pingcode.com\/wp-json\/wp\/v2\/media?parent=73002"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/docs.pingcode.com\/wp-json\/wp\/v2\/categories?post=73002"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/docs.pingcode.com\/wp-json\/wp\/v2\/tags?post=73002"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}