{"id":203944,"date":"2025-05-22T08:54:59","date_gmt":"2025-05-22T00:54:59","guid":{"rendered":"https:\/\/server.hk\/cnblog\/203944\/"},"modified":"2025-05-22T08:54:59","modified_gmt":"2025-05-22T00:54:59","slug":"java-%e4%b8%ad%e7%9a%84-fork-join-%e6%a1%86%e6%9e%b6%e6%98%af%e4%bb%80%e4%b9%88%ef%bc%9f","status":"publish","type":"post","link":"https:\/\/server.hk\/cnblog\/203944\/","title":{"rendered":"Java \u4e2d\u7684 Fork\/Join \u6846\u67b6\u662f\u4ec0\u4e48\uff1f"},"content":{"rendered":"

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

Java \u4e2d\u7684 Fork\/Join \u6846\u67b6\u662f\u4ec0\u4e48\uff1f<\/h1>\n

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

\u5728\u6587\u7ae0\u5b9e\u6218\u5f00\u53d1\u7684\u8fc7\u7a0b\u4e2d\uff0c\u6211\u4eec\u7ecf\u5e38\u4f1a\u9047\u5230\u4e00\u4e9b\u8fd9\u6837\u90a3\u6837\u7684\u95ee\u9898\uff0c\u7136\u540e\u8981\u5361\u597d\u534a\u5929\uff0c\u7b49\u95ee\u9898\u89e3\u51b3\u4e86\u624d\u53d1\u73b0\u539f\u6765\u4e00\u4e9b\u7ec6\u8282\u77e5\u8bc6\u70b9\u8fd8\u662f\u6ca1\u6709\u638c\u63e1\u597d\u3002\u4eca\u5929\u5c31\u6574\u7406\u5206\u4eab\u300aJava \u4e2d\u7684 Fork\/Join \u6846\u67b6\u662f\u4ec0\u4e48\uff1f\u300b\uff0c\u804a\u804a\uff0c\u5e0c\u671b\u53ef\u4ee5\u5e2e\u52a9\u5230\u6b63\u5728\u52aa\u529b\u8d5a\u94b1\u7684\u4f60\u3002<\/p>\n

<\/p>\n

1.\u4ec0\u4e48\u662ffork\/join\u6846\u67b6\uff1f <\/h2>\n

fork\/join \u6846\u67b6\u662f java.util.concurrent<\/strong> \u5305\u7684\u4e00\u90e8\u5206\uff0c\u5728 java 7 \u4e2d\u5f15\u5165\u3002\u5b83\u662f\u4e3a\u53ef\u4ee5\u9012\u5f52\u5730\u5212\u5206\u4e3a\u66f4\u5c0f\u7684\u5757\u7684\u4efb\u52a1\u800c\u8bbe\u8ba1\u7684\uff0c\u5176\u4e2d\u6bcf\u4e2a\u5757\u90fd\u53ef\u4ee5\u88ab\u5904\u7406\u72ec\u7acb\u3002\u8be5\u6846\u67b6\u9075\u5faa\u5206\u800c\u6cbb\u4e4b\u7684\u539f\u5219\uff0c\u975e\u5e38\u9002\u5408\u6392\u5e8f\u3001\u641c\u7d22\u548c\u5176\u4ed6\u9012\u5f52\u7b97\u6cd5\u7b49\u4efb\u52a1\u3002 <\/p>\n

2. \u5b9e\u73b0 fork\/join \u6846\u67b6 <\/h2>\n

2.1 forkjoin\u4efb\u52a1 <\/h3>\n

forkjointask<\/strong> \u662f\u53ef\u4ee5\u5728 fork\/join \u6846\u67b6\u4e2d\u8fd0\u884c\u7684\u4efb\u52a1\u7684\u57fa\u7c7b\u3002\u5b83\u63d0\u4f9b\u4e86\u6838\u5fc3\u64cd\u4f5c\uff0c\u5141\u8bb8\u4efb\u52a1\u6d3e\u751f\u65b0\u7684\u5b50\u4efb\u52a1\u5e76\u5728\u5b8c\u6210\u540e\u52a0\u5165\u5b83\u4eec\u3002 <\/p>\n

\u793a\u4f8b\uff1a<\/p>\n

import java.util.concurrent.recursivetask;\n\npublic class sumtask extends recursivetask<integer> {\n    private final int[] arr;\n    private final int start, end;\n\n    public sumtask(int[] arr, int start, int end) {\n        this.arr = arr;\n        this.start = start;\n        this.end = end;\n    }\n\n    @override\n    protected integer compute() {\n        if (end - start <= 10) {\n            int sum = 0;\n            for (int i = start; i < end; i++) {\n                sum += arr[i];\n            }\n            return sum;\n        } else {\n            int mid = (start + end) \/ 2;\n            sumtask lefttask = new sumtask(arr, start, mid);\n            sumtask righttask = new sumtask(arr, mid, end);\n\n            lefttask.fork();\n            int rightresult = righttask.compute();\n            int leftresult = lefttask.join();\n\n            return leftresult + rightresult;\n        }\n    }\n}\n<\/pre>\n
 2.2 forkjoinpool <\/h3>\n
forkjoinpool<\/strong> \u662f\u7ba1\u7406\u5de5\u4f5c\u7ebf\u7a0b\u6c60\u4ee5\u6267\u884c forkjointask<\/strong> \u5b9e\u4f8b\u7684\u4e2d\u5fc3\u7c7b\u3002\u5b83\u4f7f\u7528\u5de5\u4f5c\u7a83\u53d6\u7b97\u6cd5\uff0c\u901a\u8fc7\u5c06\u4efb\u52a1\u4ece\u7e41\u5fd9\u7ebf\u7a0b\u91cd\u65b0\u5206\u914d\u5230\u7a7a\u95f2\u7ebf\u7a0b\u6765\u4fdd\u6301\u6240\u6709\u7ebf\u7a0b\u7e41\u5fd9\u3002 <\/p>\n
\u793a\u4f8b\uff1a<\/p>\n
import java.util.concurrent.forkjoinpool;\n\npublic class forkjoinexample {\n    public static void main(string[] args) {\n        int[] arr = new int[100];\n        for (int i = 0; i < arr.length; i++) {\n            arr[i] = i + 1;\n        }\n\n        forkjoinpool pool = new forkjoinpool();\n        sumtask task = new sumtask(arr, 0, arr.length);\n\n        int result = pool.invoke(task);\n        system.out.println(\"sum: \" + result);\n    }\n}\n<\/pre>\n
 2.3 recursivetask \u4e0e recursiveaction <\/h3>\n
recursivetask <\/strong> \u5728\u4efb\u52a1\u8fd4\u56de\u7ed3\u679c\u65f6\u4f7f\u7528\uff0c\u800c recursiveaction \u5728\u4efb\u52a1\u4e0d\u8fd4\u56de\u4efb\u4f55\u7ed3\u679c\u65f6\u4f7f\u7528\u3002 <\/p>\n
\u4f7f\u7528 recursiveaction<\/strong> \u7684\u793a\u4f8b\uff1a<\/p>\n
import java.util.concurrent.recursiveaction;\n\npublic class printtask extends recursiveaction {\n    private final int[] arr;\n    private final int start, end;\n\n    public printtask(int[] arr, int start, int end) {\n        this.arr = arr;\n        this.start = start;\n        this.end = end;\n    }\n\n    @override\n    protected void compute() {\n        if (end - start <= 10) {\n            for (int i = start; i < end; i++) {\n                system.out.print(arr[i] + \" \");\n            }\n            system.out.println();\n        } else {\n            int mid = (start + end) \/ 2;\n            printtask lefttask = new printtask(arr, start, mid);\n            printtask righttask = new printtask(arr, mid, end);\n\n            invokeall(lefttask, righttask);\n        }\n    }\n}\n<\/pre>\n
 2.4 \u6f14\u793a\u548c\u7ed3\u679c <\/h3>\n
\u8fd0\u884cforkjoinexample<\/strong>\u5c06\u8f93\u51fa\u6570\u7ec4\u5143\u7d20\u7684\u603b\u548c\u3002 fork\/join \u6846\u67b6\u5c06\u4efb\u52a1\u5212\u5206\u4e3a\u66f4\u5c0f\u7684\u5757\u5e76\u5e76\u884c\u5904\u7406\u5b83\u4eec\uff0c\u663e\u793a\u51fa\u663e\u7740\u7684\u6027\u80fd\u6539\u8fdb\uff0c\u5c24\u5176\u662f\u5bf9\u4e8e\u5927\u578b\u6570\u636e\u96c6\u3002 <\/p>\n
\u4f8b\u5982\uff0c\u5c06 1 \u5230 100 \u4e4b\u95f4\u7684\u6570\u5b57\u76f8\u52a0\uff1a<\/p>\n
sum: 5050\n<\/pre>\n
\u5bf9\u4e8e printtask<\/strong> \uff0c\u6846\u67b6\u5212\u5206\u6570\u7ec4\u6253\u5370\u4efb\u52a1\uff0c\u5e76\u884c\u6267\u884c\u5e76\u540c\u65f6\u8f93\u51fa\u7247\u6bb5\uff1a<\/p>\n
1 2 3 4 5 6 7 8 9 10 \n11 12 13 14 15 16 17 18 19 20 \n...\n<\/pre>\n
 3. fork\/join \u6846\u67b6\u7684\u5404\u4e2a\u7ef4\u5ea6 <\/h2>\n
 3.1 fork\/join\u7684\u4f18\u70b9 <\/h3>\n
    \n
  •  \u6548\u7387<\/strong>\uff1a\u5229\u7528\u6240\u6709\u53ef\u7528\u7684cpu\u6838\u5fc3\uff0c\u4ece\u800c\u52a0\u5feb\u4efb\u52a1\u6267\u884c\u901f\u5ea6\u3002<\/li>\n
  •  \u53ef\u6269\u5c55\u6027<\/strong>\uff1a\u53ef\u4ee5\u901a\u8fc7\u5c06\u5927\u578b\u6570\u636e\u96c6\u5206\u89e3\u4e3a\u66f4\u5c0f\u7684\u3001\u53ef\u7ba1\u7406\u7684\u4efb\u52a1\u6765\u5904\u7406\u5b83\u4eec\u3002<\/li>\n
  •  \u5de5\u4f5c\u7a83\u53d6<\/strong>\uff1a\u901a\u8fc7\u5c06\u4efb\u52a1\u4ece\u8fc7\u8f7d\u7ebf\u7a0b\u91cd\u65b0\u5206\u914d\u5230\u7a7a\u95f2\u7ebf\u7a0b\u6765\u4fdd\u6301\u6240\u6709\u7ebf\u7a0b\u5fd9\u788c\u3002<\/li>\n<\/ul>\n
     3.2 fork\/join \u7684\u7f3a\u70b9 <\/h3>\n
      \n
    •  \u590d\u6742\u6027<\/strong>\uff1a\u9700\u8981\u4ed4\u7ec6\u8bbe\u8ba1\u548c\u7406\u89e3\u5e76\u884c\u6027\uff0c\u8fd9\u4f1a\u589e\u52a0\u4ee3\u7801\u590d\u6742\u6027\u3002<\/li>\n
    •  \u5f00\u9500<\/strong>\uff1a\u5206\u53c9\u548c\u52a0\u5165\u4efb\u52a1\u5177\u6709\u56fa\u6709\u7684\u5f00\u9500\uff0c\u8fd9\u5bf9\u4e8e\u8f83\u5c0f\u7684\u4efb\u52a1\u53ef\u80fd\u6ca1\u6709\u597d\u5904\u3002<\/li>\n
    •  \u8c03\u8bd5<\/strong>\uff1a\u7531\u4e8e\u7ebf\u7a0b\u6267\u884c\u7684\u4e0d\u786e\u5b9a\u6027\uff0c\u5e76\u884c\u4efb\u52a1\u53ef\u80fd\u5f88\u96be\u8c03\u8bd5\u3002<\/li>\n<\/ul>\n
       3.3 \u4f55\u65f6\u4f7f\u7528 fork\/join <\/h3>\n
        \n
      •  \u5927\u578b\u9012\u5f52\u95ee\u9898<\/strong>\uff1a\u5f53\u60a8\u7684\u4efb\u52a1\u81ea\u7136\u5730\u5206\u4e3a\u8f83\u5c0f\u7684\u5b50\u4efb\u52a1\u65f6\uff0c\u4f8b\u5982\u6392\u5e8f\u3001\u641c\u7d22\u548c\u77e9\u9635\u4e58\u6cd5\u3002<\/li>\n
      • 1<\/li>\n
      •  cpu \u5bc6\u96c6\u578b\u64cd\u4f5c<\/strong>\uff1a\u9700\u8981\u5bc6\u96c6 cpu \u8ba1\u7b97\u5e76\u53ef\u4ee5\u4ece\u5e76\u884c\u6267\u884c\u4e2d\u53d7\u76ca\u7684\u4efb\u52a1\u3002<\/li>\n<\/ul>\n
         4. \u7ed3\u8bba <\/h2>\n
        fork\/join \u6846\u67b6\u662f java \u4e2d\u7528\u4e8e\u4f18\u5316\u5e76\u884c\u5904\u7406\u4efb\u52a1\u7684\u5f3a\u5927\u5de5\u5177\u3002\u5b83\u64c5\u957f\u5c06\u4efb\u52a1\u5206\u89e3\u4e3a\u66f4\u5c0f\u7684\u5b50\u4efb\u52a1\uff0c\u72ec\u7acb\u6267\u884c\uff0c\u7136\u540e\u7ec4\u5408\u4ee5\u4ea7\u751f\u6700\u7ec8\u7ed3\u679c\u7684\u573a\u666f\u3002\u867d\u7136\u5b83\u5e26\u6765\u4e86\u590d\u6742\u6027\uff0c\u4f46\u591a\u6838\u73af\u5883\u4e2d\u7684\u6027\u80fd\u4f18\u52bf\u901a\u5e38\u5927\u4e8e\u5176\u7f3a\u70b9\uff0c\u4f7f\u5176\u6210\u4e3a\u89e3\u51b3 cpu \u9650\u5236\u548c\u5927\u578b\u9012\u5f52\u95ee\u9898\u7684\u7edd\u4f73\u9009\u62e9\u3002 <\/p>\n
        \u9605\u8bfb\u66f4\u591a\u5e16\u5b50<\/strong>\uff1a\u4ec0\u4e48\u662f java \u4e2d\u7684 fork\/join \u6846\u67b6\uff1f<\/p>\n
        \u4ee5\u4e0a\u5c31\u662f\u672c\u6587\u7684\u5168\u90e8\u5185\u5bb9\u4e86\uff0c\u662f\u5426\u6709\u987a\u5229\u5e2e\u52a9\u4f60\u89e3\u51b3\u95ee\u9898\uff1f\u82e5\u662f\u80fd\u7ed9\u4f60\u5e26\u6765\u5b66\u4e60\u4e0a\u7684\u5e2e\u52a9\uff0c\u8bf7\u5927\u5bb6\u591a\u591a\u652f\u6301\uff01\u66f4\u591a\u5173\u4e8e\u6587\u7ae0\u7684\u76f8\u5173\u77e5\u8bc6\uff0c\u4e5f\u53ef\u5173\u6ce8\u516c\u4f17\u53f7\u3002<\/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":"
        Java \u4e2d\u7684 Fork\/Joi...<\/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-203944","post","type-post","status-publish","format-standard","hentry","category-4925"],"_links":{"self":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/203944","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=203944"}],"version-history":[{"count":0,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/203944\/revisions"}],"wp:attachment":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/media?parent=203944"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/categories?post=203944"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/tags?post=203944"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}