{"id":203243,"date":"2025-05-22T10:32:19","date_gmt":"2025-05-22T02:32:19","guid":{"rendered":"https:\/\/server.hk\/cnblog\/203243\/"},"modified":"2025-05-22T10:32:19","modified_gmt":"2025-05-22T02:32:19","slug":"%e6%98%af%e4%b8%80%e4%b8%aajava","status":"publish","type":"post","link":"https:\/\/server.hk\/cnblog\/203243\/","title":{"rendered":"\u662f\u4e00\u4e2aJava"},"content":{"rendered":"

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

\u662f\u4e00\u4e2aJava<\/h1>\n

<\/i>\u6536\u85cf<\/span> <\/p>\n

\u5404\u4f4d\u5c0f\u4f19\u4f34\u4eec\uff0c\u5927\u5bb6\u597d\u5440\uff01\u770b\u770b\u4eca\u5929\u6211\u53c8\u7ed9\u5404\u4f4d\u5e26\u6765\u4e86\u4ec0\u4e48\u6587\u7ae0\uff1f\u672c\u6587\u6807\u9898\u662f<\/span>\u300a\u662f\u4e00\u4e2aJava\u300b<\/span>\uff0c\u5f88\u660e\u663e\u662f\u5173\u4e8e\u6587\u7ae0<\/span>\u7684\u6587\u7ae0\u54c8\u54c8\u54c8\uff0c\u5176\u4e2d\u5185\u5bb9\u4e3b\u8981\u4f1a\u6d89\u53ca\u5230<\/span>\u7b49\u7b49\uff0c\u5982\u679c\u80fd\u5e2e\u5230\u4f60\uff0c\u89c9\u5f97\u5f88\u4e0d\u9519\u7684\u8bdd\uff0c\u6b22\u8fce\u5404\u4f4d\u591a\u591a\u70b9\u8bc4\u548c\u5206\u4eab\uff01<\/span><\/p>\n

<\/p>\n

var \u662f jdk 10 \u4e2d\u5f15\u5165\u7684\u4e00\u4e2a\u6784\u9020\uff0c\u5b83\u7528\u4e8e\u521b\u5efa\u672a\u6307\u5b9a\u6570\u636e\u7c7b\u578b\u7684\u53d8\u91cf\uff0c\u800c\u662f\u7531\u7f16\u8bd1\u5668\u6765\u63a8\u65ad\u53d8\u91cf\u7684\u6570\u636e\u7c7b\u578b\u3002\u8fd9\u5c31\u662f\u6240\u8c13\u7684\u7c7b\u578b\u63a8\u65ad<\/strong>\u3002<\/p>\n

var \u4e0d\u662f java \u7684\u5173\u952e\u5b57<\/em> \u6216 \u5173\u952e\u5b57<\/em>\uff0c\u800c\u662f\u8be5\u8bed\u8a00\u7684\u4fdd\u7559\u540d\u79f0<\/strong>\uff0c\u56e0\u4e3a\u5b83\u662f\u7a0d\u540e\u5f15\u5165\u7684\u5e76\u4e14\u6709\u53ef\u80fd\u88ab\u7528\u4f5c\u67d0\u4e9b\u53d8\u91cf\u3001\u7c7b\u3001\u65b9\u6cd5\u7b49\u7684\u540d\u79f0\u3002\u5728\u5f15\u5165\u4e4b\u524d\u7684\u4ee3\u7801\u4e2d\u3002<\/p>\n

\n

\u7c7b\u578b\u63a8\u65ad<\/strong>\u662f\u4e00\u4e2a\u8fc7\u7a0b\uff0c\u5728\u8fd9\u4e2a\u8fc7\u7a0b\u4e2d\uff0c\u7f16\u8bd1\u5668\u53ef\u4ee5\u6839\u636e\u5206\u914d\u7ed9\u53d8\u91cf\u7684\u503c\u6765\u786e\u5b9a\u53d8\u91cf\u7684\u6570\u636e\u7c7b\u578b\uff0c\u800c\u4e0d\u662f\u7528\u5176\u6570\u636e\u7c7b\u578b\u6765\u58f0\u660e\u53d8\u91cf\uff0c\u8fd9\u53ef\u4ee5\u901a\u8fc7\u521b\u5efa\u5217\u8868\u5e76\u7701\u7565\u83f1\u5f62\u8fd0\u7b97\u7b26\u4e2d\u7684\u6570\u636e\u7c7b\u578b\u6765\u770b\u5230\uff0c\u5982\u4e0b\u6240\u793a\uff1a<\/p>\n<\/blockquote>\n

\/\/ omite el tipo de dato dentro del operador diamante\nlist<integer> list = new arraylist<>();\n\n\/\/ usa el tipo de dato dentro del operador diamante\nlist<integer> list = new arraylist<integer>();\n<\/pre>\n
 java \u4e2d\u5982\u4f55\u4f7f\u7528 var\uff1f <\/h2>\n
\u8981\u4f7f\u7528 var \u58f0\u660e\u53d8\u91cf\uff0c\u8bf7\u6267\u884c\u4ee5\u4e0b\u64cd\u4f5c\uff1a<\/p>\n
var nombredelavariable = valor;\n<\/pre>\n
var n = \"john\";\n<\/pre>\n
\u5728\u8fd9\u79cd\u60c5\u51b5\u4e0b\uff0c\u7f16\u8bd1\u5668\u63a8\u65ad\u53d8\u91cf n \u662f string \u7c7b\u578b\uff0c\u56e0\u4e3a\u5b83\u88ab\u5206\u914d\u4e86 string \u7c7b\u578b\u7684\u503c\uff0c\u5e76\u4e14\u7701\u7565\u4e86\u58f0\u660e\u6570\u636e\u7c7b\u578b\u7684\u64cd\u4f5c\uff0c\u5373\u4e0d\u5fc5\u6267\u884c\u4ee5\u4e0b\u64cd\u4f5c\uff1a <\/p>\n
string n = \"john\";\n<\/pre>\n
\u5982\u679c\u53d8\u91cf\u7684\u503c\u66f4\u6539\u4e3a 10\uff0c\u7f16\u8bd1\u5668\u73b0\u5728\u4f1a\u63a8\u65ad\u53d8\u91cf n \u7684\u7c7b\u578b\u4e3a int\uff1a<\/p>\n
var n = 10;\n<\/pre>\n
\u7c7b\u4f3c\u5730\uff0c\u5982\u679c\u53d8\u91cf\u7684\u503c\u66f4\u6539\u4e3a 10.0\uff0c\u7f16\u8bd1\u5668\u73b0\u5728\u4f1a\u63a8\u65ad\u53d8\u91cf n \u7684\u7c7b\u578b\u4e3a double\uff1a<\/p>\n
var n = 10.0;\n<\/pre>\n
\u5373\u4f7f\u53d8\u91cf\u7684\u503c\u66f4\u6539\u4e3a random \u5b9e\u4f8b\uff0c\u7f16\u8bd1\u5668\u73b0\u5728\u4e5f\u4f1a\u63a8\u65ad\u53d8\u91cf n \u7684\u7c7b\u578b\u4e3a random\uff1a<\/p>\n
var n = new random();\n<\/pre>\n
 var \u7684\u9650\u5236 <\/h2>\n
    \n
  • \u5728\u7c7b\u4e2d\u58f0\u660e\u5c5e\u6027\u65f6\uff0c\u4e0d\u80fd\u4f7f\u7528 var \u6765\u58f0\u660e\u5b83\u4eec\uff0c\u56e0\u4e3a\u7f16\u8bd1\u5668\u65e0\u6cd5\u63a8\u65ad\u5c5e\u6027\u7684\u6570\u636e\u7c7b\u578b\uff0c\u56e0\u6b64\u5fc5\u987b\u663e\u5f0f\u58f0\u660e\u6570\u636e\u7c7b\u578b\u3002 <\/li>\n<\/ul>\n
    public class person {\n    private var name; \/\/ error\n}\n<\/pre>\n
    public class person {\n    private string name;\n}\n<\/pre>\n
      \n
    •  var \u4e0d\u80fd\u7528\u4e8e\u58f0\u660e\u65b9\u6cd5\u6216\u51fd\u6570\u7684\u53c2\u6570\uff0c\u56e0\u4e3a\u7f16\u8bd1\u5668\u65e0\u6cd5\u63a8\u65ad\u53c2\u6570\u7684\u6570\u636e\u7c7b\u578b\uff0c\u56e0\u6b64\u5fc5\u987b\u663e\u5f0f\u58f0\u660e\u6570\u636e\u7c7b\u578b\u3002 <\/li>\n<\/ul>\n
      public void sayhello(var name) { \/\/ error\n    system.out.println(\"hello \" + name);\n}\n<\/pre>\n
        \n
      • \u5176\u4ed6\u9650\u5236\u4e4b\u4e00\u662f\uff0c\u5728\u58f0\u660e\u503c\u4e3a null \u7684\u53d8\u91cf\u65f6\u4e0d\u80fd\u4f7f\u7528 var\uff0c\u56e0\u4e3a\u81f3\u5c11\u5728 java \u4e2d\uff0cnull \u4e0d\u662f\u6709\u6548\u7684\u6570\u636e\u7c7b\u578b\uff0c\u5e76\u4e14\u7c7b\u578b\u63a8\u65ad\u5728\u8fd9\u79cd\u60c5\u51b5\u4e0b\u4e0d\u8d77\u4f5c\u7528\u3002 <\/li>\n<\/ul>\n
        var y = null; \/\/ error\n<\/pre>\n
          \n
        • \u6211\u4eec\u4e5f\u4e0d\u80fd\u53ea\u4f7f\u7528var\u6765\u58f0\u660e\u53d8\u91cf\u800c\u4e0d\u521d\u59cb\u5316\u5b83\uff0c\u9700\u8981\u5728\u58f0\u660e\u53d8\u91cf\u65f6\u7ed9\u53d8\u91cf\u8d4b\u503c\u3002 <\/li>\n<\/ul>\n
          var x; \/\/ error\nx = 10;\n<\/pre>\n
            \n
          • \u5f53\u5728\u4e00\u884c\u4e2d\u58f0\u660e\u591a\u4e2a\u76f8\u540c\u7c7b\u578b\u7684\u53d8\u91cf\uff08\u590d\u5408\u58f0\u660e\uff09\u65f6\uff0c\u4e0d\u80fd\u4f7f\u7528 var\uff0c\u5426\u5219\u5fc5\u987b\u4f7f\u7528\u5177\u6709\u663e\u5f0f\u6570\u636e\u7c7b\u578b\u7684\u53d8\u91cf\u3002 <\/li>\n<\/ul>\n
            var x = 1, y = 10, z = 10; \/\/ error\nint x = 1, y = 10, z = 10;\n<\/pre>\n
              \n
            •  var \u4e0d\u80fd\u7528\u4e8e\u58f0\u660e lambda\u3001\u65b9\u6cd5\u5f15\u7528\u6216\u7c7b\u4f3c\u5185\u5bb9\uff0c\u4f8b\u5982\uff1a <\/li>\n<\/ul>\n
              var plusone = (int x) -> x + 1; \/\/ error\n\n\/\/ se tiene que declarar de la siguiente manera\nfunction<integer, integer> plusone = x -> x + 1;\n<\/pre>\n
              \u5728\u5176\u4f59\u60c5\u51b5\u4e0b\uff0cvar \u53ef\u4ee5\u6309\u6b63\u5e38\u65b9\u5f0f\u4f7f\u7528\uff0c\u56e0\u4e3a\u5b83\u5fc5\u987b\u5728\u4ee3\u7801\u672c\u5730\u4f7f\u7528\uff0c\u800c\u4e0d\u662f\u5728\u7c7b\u7684\u5c5e\u6027\u3001\u65b9\u6cd5\u7684\u53c2\u6570\u7b49\u7ea7\u522b\u4f7f\u7528\u3002\u4f8b\u5982\uff1a<\/p>\n
              public class main {\n\n    public static void main(string[] args) {\n        var fullname = fullname(\"jonh\", \"doe\");\n        system.out.println(fullname);\n    }\n\n    public static string fullname(string firstname, string lastname) {\n        var fullname = firstname + \" \" + lastname;\n        return fullname;\n    }\n\n}\n<\/pre>\n
              var names = new string[] { \"john\", \"jane\", \"alice\", \"bob\" }; \/\/ inferred as string[]\nvar cities = arrays.aslist(\"barcelona\", \"madrid\", \"paris\", \"london\"); \/\/ inferred as list<string>\nvar numbers = list.of(1, 2, 3, 4, 5); \/\/ inferred as list<integer>\n<\/pre>\n
              \u9700\u8981\u8003\u8651\u7684\u662f\uff0c\u5728\u67d0\u4e9b\u60c5\u51b5\u4e0b\u4f7f\u7528 var \u4f1a\u964d\u4f4e\u4ee3\u7801\u7684\u53ef\u8bfb\u6027\uff0c\u56e0\u4e3a java \u662f\u4e00\u79cd\u4e3a\u53d8\u91cf\u5206\u914d\u9884\u5148\u5df2\u77e5\u7684\u6570\u636e\u7c7b\u578b\u7684\u8bed\u8a00\uff0c\u5e76\u4e14\u5728\u4f7f\u7528 var \u65f6\u53ef\u80fd\u4f1a\u4e22\u5931\u8be5\u4fe1\u606f\uff0c\u56e0\u6b64 var \u53ef\u4ee5\u7528\u4e8e\u53ef\u4ee5\u6e05\u695a\u5730\u63a8\u65ad\u6570\u636e\u7c7b\u578b\u5e76\u4e14\u4e0d\u4e22\u5931\u4ee3\u7801\u53ef\u8bfb\u6027\u7684\u60c5\u51b5\u3002<\/p>\n
              \/\/ ambas declaraciones son v\u00e1lidas y son del mismo tipo\nvar service = new remoteuserservice();\nremoteuserservice service = new remoteuserservice();\n<\/pre>\n
              \n
              \u91cd\u8981\u7684\u662f\u4e0d\u8981\u5c06\u7c7b\u578b\u63a8\u65ad\u4e0e java \u4f5c\u4e3a\u5f3a\u7c7b\u578b\u8bed\u8a00\u76f8\u6df7\u6dc6\u3002\u4f7f\u7528 var \u5e76\u4e0d\u4f7f\u53d8\u91cf\u6210\u4e3a\u52a8\u6001\u7c7b\u578b\u53d8\u91cf\uff0c\u800c\u662f\u7f16\u8bd1\u5668\u5728\u7f16\u8bd1\u65f6\u63a8\u65ad\u53d8\u91cf\u7684\u6570\u636e\u7c7b\u578b\u3002\u6240\u4ee5\u4f60\u4e0d\u80fd\u58f0\u660e\u4e00\u4e2aint\u7c7b\u578b\u7684\u53d8\u91cf\uff0c\u7136\u540e\u7ed9\u5b83\u8d4b\u4e00\u4e2astring\u7c7b\u578b\u7684\u503c\u3002<\/p>\n<\/blockquote>\n
              var x = 5;\nx = \"Hello\"; \/\/ Error\n<\/pre>\n
              \u672c\u7bc7\u5173\u4e8e\u300a\u662f\u4e00\u4e2aJava\u300b\u7684\u4ecb\u7ecd\u5c31\u5230\u6b64\u7ed3\u675f\u5566\uff0c\u4f46\u662f\u5b66\u65e0\u6b62\u5883\uff0c\u60f3\u8981\u4e86\u89e3\u5b66\u4e60\u66f4\u591a\u5173\u4e8e\u6587\u7ae0\u7684\u76f8\u5173\u77e5\u8bc6\uff0c\u8bf7\u5173\u6ce8\u516c\u4f17\u53f7\uff01<\/p>\n
                    \u7248\u672c\u58f0\u660e \u672c\u6587\u8f6c\u8f7d\u4e8e\uff1adev.to \u5982\u6709\u4fb5\u72af\uff0c\u8bf7\u8054\u7cfb\u5220\u9664<\/p>\n","protected":false},"excerpt":{"rendered":"
              \u662f\u4e00\u4e2aJava \u6536\u85cf \u5404\u4f4d\u5c0f\u4f19\u4f34...<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[4925],"tags":[],"class_list":["post-203243","post","type-post","status-publish","format-standard","hentry","category-4925"],"_links":{"self":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/203243","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/comments?post=203243"}],"version-history":[{"count":0,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/203243\/revisions"}],"wp:attachment":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/media?parent=203243"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/categories?post=203243"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/tags?post=203243"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}