{"id":515,"date":"2024-03-01T09:05:39","date_gmt":"2024-03-01T01:05:39","guid":{"rendered":"https:\/\/pidanxia.ink\/?p=515"},"modified":"2024-03-01T01:12:44","modified_gmt":"2024-02-29T17:12:44","slug":"streamapi","status":"publish","type":"post","link":"https:\/\/pidanxia.ink\/streamapi\/","title":{"rendered":"StreamAPI\u4ecb\u7ecd\u4ee5\u53ca\u57fa\u672c\u4f7f\u7528"},"content":{"rendered":"

\u5f15\u5165<\/h2>\n

Stream\u5c31\u662f\u6d41\uff0c\u6d41\u5f0f\u64cd\u4f5c\u5c31\u8ddf\u751f\u6d3b\u4e2d\u7684\u6d41\u6c34\u7ebf\u4e00\u6837\u3002\u6bd4\u5982\u6211\u6709\u4e00\u6279\u539f\u6750\u6599\uff0c\u7ecf\u8fc7\u6d41\u6c34\u7ebf \u6311\u9009–> \u6e05\u6d17 –> \u5305\u88c5\u3002\u5c31\u53d8\u6210\u4e86\u4e00\u4e2a\u4ea7\u54c1\u4e86\u3002<\/p>\n

Stream\u6d41\u5c31\u597d\u6bd4\u6211\u9700\u8981\u7ec4\u88c5\u4e00\u6761\u6d41\u6c34\u7ebf\uff0c\u5f53\u6570\u636e\u5c31\u50cf\u539f\u6599\u4e00\u6837\u6e90\u6e90\u4e0d\u65ad\u7684\u8d70\u4e0a\u6d41\u6c34\u7ebf\u7684\u4f20\u9001\u5e26\u4e0a\uff0c\u7ecf\u8fc7\u5404\u79cd\u6b65\u9aa4\u7684\u5904\u7406\uff0c\u77e5\u9053\u8d70\u5b8c\u6240\u6709\u7684\u6d41\u6c34\u7ebf\uff0c\u539f\u6599\u6570\u636e\u5c31\u7ec4\u88c5\u5b8c\u6210\u4e86\uff0c\u6700\u7ec8\u53d8\u6210\u4e00\u4e2a\u6211\u60f3\u8981\u7684\u4e1c\u897f\u3002<\/p>\n

\u54cd\u5e94\u5f0f\u7f16\u7a0b\u8ddf\u4f20\u7edf\u7684\u547d\u4ee4\u884c\u7f16\u7a0b\u7684\u601d\u60f3\u6709\u4e00\u4e2a\u91cd\u5927\u7684\u5dee\u5f02\uff1a<\/p>\n

\u547d\u4ee4\u884c\u7f16\u7a0b\uff1a\u62ff\u5230\u4e00\u5806\u6570\u636e\u4e4b\u540e\uff0c\u9700\u8981\u81ea\u5df1\u5199for\u5faa\u73af\u63a8\u8fdb\uff0c\u9700\u8981\u81ea\u5df1\u63a7\u5236\u5faa\u73af\u903b\u8f91\uff0c\u6bd4\u5982\u5927\u4e8e2\u4e86\u600e\u4e48\u529e\uff0c\u5c0f\u4e8e3\u4e86\u53c8\u600e\u4e48\u529e\u3002
\n\u54cd\u5e94\u5f0f\u7f16\u7a0b\uff1a\u62ff\u5230\u4e00\u5806\u6570\u636e\u4e4b\u540e\uff0c\u4ed6\u9700\u8981\u7ecf\u8fc7123456\u6b65\u7684\u6d41\u6c34\u7ebf\uff0c\u6765\u8f6c\u5316\u6210\u6211\u9700\u8981\u7684\u6570\u636e\u6216\u8005\u6570\u636e\u96c6\u3002<\/p>\n

\n

StreamAPI\u4ecb\u7ecd<\/h2>\n

\"image-20240226100008783\"<\/div><\/p>\n

\u6d41\u662f\u4ec0\u4e48\uff1f\u6d41\u91cc\u9762\u6709\u4ec0\u4e48\uff1f
\n\u6211\u4eec\u53ef\u4ee5\u628a\u4ed6\u6bd4\u55bb\u4e3a\u4e00\u6761\u751f\u4ea7\u6d41\u6c34\u7ebf\uff0c\u6d41\u6c34\u7ebf\u7684\u4f20\u9001\u5e26\u4e0a\u5c31\u4f1a\u6709\u4e00\u4e9b\u4e1c\u897f\uff0c\u8fd9\u4e9b\u4e1c\u897f\u4f1a\u4ece\u539f\u6599\u4e00\u6b65\u6b65\u7684\u52a0\u5de5\u6210\u4e3a\u4e00\u4e2a\u5b8c\u6574\u7684\u4ea7\u54c1\u3002
\n\u58f0\u660e\u5f0f\u5904\u7406\u96c6\u5408\u6570\u636e<\/strong>\uff0c\u5305\u62ec\uff1a\u7b5b\u9009\u3001\u8f6c\u6362\u3001\u7ec4\u5408\u7b49\uff0c\u800c\u8fd9\u4e9b\u6570\u636e\uff0c\u5c31\u7b97\u6d41\u91cc\u9762\u7684\u539f\u6599\u3002<\/p>\n

Stream\u6d41\u7684\u601d\u60f3\uff1a<\/p>\n

    \n
  1. \u9996\u5148\u5f97\u6709\u4e00\u4e2a\u6d41<\/strong>\uff0c\u6d41\u91cc\u9762\u53ef\u4ee5\u6709\u4e00\u5806\u6570\u636e\uff0c\u6216\u8005\u4e00\u4e2a\u6570\u636e\uff0c\u751a\u81f3\u662f\u7a7a\u6d41\u90fd\u53ef\u4ee5\u3002\u53cd\u6b63\u5f97\u6709\u4e00\u4e2a\u6d41\u7ed9\u6211\u64cd\u4f5c\u3002\u5c31\u76f8\u5f53\u4e8e\uff0c\u4e00\u6761\u6d41\u6c34\u7ebf\uff0c\u53ef\u4ee5\u6ca1\u6709\u539f\u6750\u6599\uff0c\u4f46\u662f\u5f97\u6709\u5b58\u653e\u539f\u6750\u6599\u7684\u4ed3\u5e93\uff0c\u6709\u4ed3\u5e93\uff0c\u6d41\u6c34\u7ebf\u624d\u80fd\u6709\u8d77\u70b9\uff0c\u6d41\u6c34\u7ebf\u624d\u80fd\u8fdb\u884c\u4e0b\u53bb\u3002<\/li>\n
  2. \u4e2d\u95f4\u64cd\u4f5c<\/strong>\uff0c\u5c31\u662f\u6d41\u6c34\u7ebf\u7684\u6bcf\u4e00\u4e2a\u6b65\u9aa4\u3002\u6bd4\u5982\u6211\u60f3\u6311\u51fa\u6765\u539f\u6599\u4e2d\u7684\u7455\u75b5\u54c1\uff0c\u90a3\u4e48\u6d41\u6c34\u7ebf\u7684\u7b2c\u4e00\u4e2a\u6b65\u9aa4\u5c31\u662f\u9009\u54c1\u3002\u6bcf\u4e00\u4e2a\u6d41\u6c34\u7ebf\u7684\u6b65\u9aa4\uff0c\u5c31\u53eb\u505a\u6d41\u7684\u4e2d\u95f4\u64cd\u4f5c\u3002<\/li>\n
  3. \u65b0\u6d41<\/strong>\uff0c\u5728\u7ecf\u8fc7\u4e00\u7cfb\u5217\u7684\u4e2d\u95f4\u64cd\u4f5c\u4e4b\u540e\uff0c\u6700\u7ec8\u4f1a\u5f97\u5230\u4e00\u4e2a\u65b0\u6d41\u3002\u6bd4\u5982\u6d41\u6c34\u7ebf\u5bf9\u539f\u6750\u6599\u8fdb\u884c\u4e86\u9009\u54c1\uff0c\u52a0\u5de5\uff0c\u5206\u7ec4\uff0c\u5305\u88c5\uff0c\u5c31\u5f97\u5230\u4e86\u4e00\u4e9b\u65b0\u7684\u4ea7\u54c1\u3002<\/li>\n
  4. \u7ec8\u6b62\u64cd\u4f5c<\/strong>\uff0c\u5f97\u5230\u4e86\u65b0\u6d41\u4e4b\u540e\u4e5f\u4e0d\u80fd\u76f4\u63a5\u4f7f\u7528\uff0c\u56e0\u4e3a\u6d41\u662f\u52a8\u6001\u7684\u3002\u6bd4\u5982\u539f\u6750\u6599\u904d\u5386\u5b8c\u6d41\u6c34\u7ebf\u7684\u6240\u6709\u64cd\u4f5c\u4e86\uff0c\u4f46\u662f\u8fd8\u653e\u5728\u4f20\u9001\u5e26\u4e0a\u4f20\u9001\u7740\u3002\u8fd9\u65f6\u5019\uff0c\u6211\u4eec\u9700\u8981\u628a\u4ea7\u54c1\u4ece\u4f20\u9001\u5e26\u4e0a\u62ff\u4e0b\u6765\uff0c\u7edf\u8ba1\u6570\u91cf\u6216\u8005\u62ff\u5230\u6700\u5927\u503c\u3002\u8fd9\u4e2a\u5c31\u53eb\u505a\u7ec8\u6b62\u64cd\u4f5c<\/strong>\u3002<\/li>\n
  5. \u7ed3\u679c<\/strong>\uff0c\u7ec8\u6b62\u64cd\u4f5c\u4e2d\uff0c\u6211\u4eec\u628a\u65b0\u6d41\u7684\u5143\u7d20\u62ff\u51fa\u6765\u4e86\u6216\u8005\u7edf\u8ba1\u6570\u91cf\u4e86\u4e4b\u7c7b\u7684\uff0c\u5f97\u5230\u67d0\u4e2a\u7ed3\u679c\u4e86\uff0c\u90a3\u4e48\u6574\u4e2a\u6d41\u64cd\u4f5c\u5c31\u7ed3\u675f\u4e86\u3002<\/li>\n<\/ol>\n

    \u603b\u7ed3<\/strong>\uff1a\u4e00\u4e2a\u6d41\u8981\u5904\u7406\u7ed3\u675f\uff0c\u6709\u4e09\u5927\u5173\u952e\u6b65\u9aa4\uff1a<\/p>\n

      \n
    1. \u521b\u5efa\u6d41<\/li>\n
    2. \u6709\u4e2d\u95f4\u64cd\u4f5c<\/li>\n
    3. \u6709\u7ec8\u6b62\u64cd\u4f5c<\/li>\n<\/ol>\n
      \n

      \u4f8b\u5b50\uff1a<\/h2>\n

      List<Integer> list = List.of(1, 2, 3, 4, 5, 6, 7, 8, 9, 10);<\/code>
      \n\u6211\u9700\u8981\u627e\u51fa\u4e86list<\/code>\u5217\u8868\u91cc\u6700\u5927\u7684\u5076\u6570<\/p>\n

      \u65b9\u6cd5\u4e00\uff1a\u7528for\u5faa\u73af<\/p>\n

              \/\/ \u65b9\u6cd51\uff1a\u7528for\u5faa\u73af\n        int max = 0;\n        for(Integer integer : list){\n            if(integer % 2 ==0){\n                \/\/ \u662f\u5076\u6570\uff0c\u548cmax\u8fdb\u884c\u6bd4\u8f83\u4ea4\u6362\n                max = integer >= max ? integer : max;\n            }\n        }\n        System.out.println(\"\u6700\u5927\u5076\u6570\uff1a\" + max);\n<\/code><\/pre>\n
      \u65b9\u6cd5\u4e8c\uff1a\u7528StreamAPI<\/p>\n
              \/\/ \u65b9\u6cd52\uff1a\u7528Stream\u6d41\n        list.stream()\n                .filter(ele -> {\n                    System.out.println(\"\u6b63\u5728filter\uff1a\" + ele);\n                    return ele % 2 == 0;\n                })\n                .max(Integer::compareTo)\n                .ifPresent(System.out::println);\n<\/code><\/pre>\n
      \n
      \u6d41\u7ba1\u9053\u7ec4\u6210\uff1a<\/h2>\n
      \u89e3\u6790\u4f8b\u5b50\u4e8c\uff1a<\/p>\n
      \u9996\u5148\u6765\u8ba4\u8bc6\u51e0\u4e2a\u540d\u8bcd\uff1a<\/p>\n
      Stream Pipeline\uff1a\u6d41\u6c34\u7ebf\u3001\u6d41\u7ba1\u9053
      \nIntermediate Operations\uff1a\u4e2d\u95f4\u64cd\u4f5c<\/strong>
      \nTerminal Operation\uff1a\u7ec8\u6b62\u64cd\u4f5c<\/strong><\/p>\n
      Stream\u6240\u6709\u6570\u636e\u548c\u64cd\u4f5c\u88ab\u7ec4\u5408\u6210\u6d41\u7ba1\u9053\u3002<\/p>\n
        \n
      1. \u4e00\u4e2a\u6570\u636e\u6e90\uff08\u53ef\u4ee5\u662f\u4e00\u4e2a\u6570\u7ec4\u3001\u96c6\u5408\u3001\u751f\u6210\u5668\u51fd\u6570\u3001I\/O\u7ba1\u9053\uff09<\/li>\n
      2. \u96f6\u4e2a\u6216\u591a\u4e2a\u4e2d\u95f4\u64cd\u4f5c\uff08\u5c06\u4e00\u4e2a\u6d41\u53d8\u5f62\u6210\u53e6\u4e00\u4e2a\u6d41\uff09<\/li>\n
      3. \u4e00\u4e2a\u7ec8\u6b62\u64cd\u4f5c\uff08\u4ea7\u751f\u6700\u7ec8\u7ed3\u679c\uff09<\/li>\n<\/ol>\n
        \u6d41\u662f\u60f0\u6027\u7684<\/strong>\u3002\u53ea\u6709\u5728\u542f\u52a8\u6700\u7ec8\u64cd\u4f5c\u65f6\u624d\u4f1a\u5bf9\u6570\u636e\u6e90\u8fdb\u884c\u8ba1\u7b97\uff0c\u800c\u4e14\u53ea\u6709\u5728\u9700\u8981\u65f6\u624d\u4f1a\u6d88\u8017\u5143\u7d20\u3002
        \n\u4ec0\u4e48\u610f\u601d\u5462\uff1f\u8ba9\u6211\u4eec\u6765\u770b\u4f8b\u5b50\u4e8c\uff1a<\/p>\n
                list.stream()\n                \/\/ intermediate operation.\u4e2d\u95f4\u64cd\u4f5c\n                .filter(ele -> {\n                    System.out.println(\"\u6b63\u5728filter\uff1a\" + ele);\n                    return ele % 2 == 0;\n                });\n<\/code><\/pre>\n
        \u5982\u679c\u662f\u50cf\u4e0a\u9762\u4e00\u6837\u5199\u7684\u8bdd\uff0c\u6ca1\u6709\u540e\u9762\u7684.max(Integer::compareTo).ifPresent(System.out::println);<\/code>\u7684\u8bdd\uff0c\u6253\u5370\u8bed\u53e5\u662f\u4e0d\u4f1a\u6267\u884c\u7684\u3002
        \n
        \"image-20240226172240272\"<\/div><\/p>\n
        \u56e0\u4e3a\u8fd8\u6ca1\u6709\u5230\u7ec8\u6b62\u64cd\u4f5c\uff0c\u6240\u4ee5\u4e0d\u4f1a\u5bf9\u6570\u636e\u6e90\u8fdb\u884c\u8ba1\u7b97\u3002\u6bd4\u5982\u4e00\u6761\u6d41\u6c34\u7ebf\uff0c\u4f20\u9001\u5e26\u90fd\u4fee\u597d\u4e86\uff0c\u4f46\u662f\u6700\u540e\u7684\u6536\u8d27\u73af\u8282\u6ca1\u505a\u597d\uff0c\u76f8\u5f53\u4e8e\u539f\u6599\u5728\u6d41\u6c34\u7ebf\u4e0a\u52a0\u5de5\u5b8c\u6210\u540e\uff0c\u6ca1\u5730\u65b9\u53ef\u53bb\uff0c\u90a3\u4e48\u8fd9\u6761\u6d41\u6c34\u7ebf\u662f\u4e0d\u4f1a\u542f\u52a8\u7684\u3002<\/p>\n
        \u5728\u4f8b\u5b50\u4e8c\u4e2d\uff0c<\/p>\n
        filter()\u65b9\u6cd5<\/code>\u5728\u6e90\u7801\u7684\u6587\u6863\u4e2d\u6709\u5199\u662fintermediate operation<\/code>\u4e2d\u95f4\u64cd\u4f5c\u3002
        \n
        \"image-20240226173122888\"<\/div><\/p>\n
        \u800cmax()\u65b9\u6cd5<\/code>\u5219\u662fterminal operation<\/code>\u7ec8\u6b62\u64cd\u4f5c\u3002
        \n
        \"image-20240226173247642\"<\/div><\/p>\n
        max()\u65b9\u6cd5<\/code>\u540e\uff0c\u8fd8\u53ef\u4ee5\u4f20\u4e00\u4e2a\u6761\u4ef6\u5224\u65adifPresent()<\/code>\uff0c
        \n
        \"image-20240226174559387\"<\/div><\/p>\n
                \/\/ \u65b9\u6cd52\uff1a\u7528Stream\u6d41\n        list.stream()\n                \/\/ intermediate operation.\u4e2d\u95f4\u64cd\u4f5c\n                .filter(ele -> {\n                    System.out.println(\"\u6b63\u5728filter\uff1a\" + ele);\n                    return ele % 2 == 0;\n                })\n\n                \/\/terminal operation.\u7ec8\u6b62\u64cd\u4f5c\u3002\u8fc7\u6ee4\u51fa\u6211\u4eec\u60f3\u8981\u7684\u503c\uff0c\u5982\u679c\u65ad\u8a00\u8fd4\u56detrue\u5c31\u7b97\u6211\u4eec\u8981\u7684\u503c\uff0c\u5982\u679c\u65ad\u8a00\u8fd4\u56defalse\uff0c\u5c31\u5ffd\u7565\u6389\n                .max(Integer::compareTo)\n\n                \/\/ \u7b80\u5199:.ifPresent(ele -> System.out.println(\"\u6700\u5927\u5076\u6570\uff1a\" + ele));\n                .ifPresent(System.out::println); \/\/\u5982\u679c\u5b58\u5728\u8fd9\u4e2a\u6570\uff0c\u5c31\u8f93\u51fa\n<\/code><\/pre>\n
        \n  Stream().filter()<\/code>\u662f\u4e00\u4e2a\u4e2d\u95f4\u64cd\u4f5c\uff0c\u7528\u4e8e\u7b5b\u9009\u6ee1\u8db3\u7279\u5b9a\u6761\u4ef6\u7684\u5143\u7d20\uff0c\u5e76\u751f\u6210\u4e00\u4e2a\u65b0\u7684\u6d41\u3002<\/p>\n
          \u5b83\u63a5\u53d7\u4e00\u4e2aPredicate\u51fd\u6570\u5f0f\u63a5\u53e3\u4f5c\u4e3a\u53c2\u6570\uff0c\u8be5\u63a5\u53e3\u5b9a\u4e49\u4e86\u4e00\u4e2a\u7528\u4e8e\u5224\u65ad\u5143\u7d20\u662f\u5426\u6ee1\u8db3\u6761\u4ef6\u7684\u65b9\u6cd5\u3002filter()\u65b9\u6cd5\u4f1a\u904d\u5386\u6d41\u4e2d\u7684\u6bcf\u4e2a\u5143\u7d20\uff0c\u5bf9\u6bcf\u4e2a\u5143\u7d20\u5e94\u7528Predicate\u63a5\u53e3\u7684test()\u65b9\u6cd5\uff0c\u5982\u679c\u8fd4\u56detrue\uff0c\u5219\u5c06\u8be5\u5143\u7d20\u5305\u542b\u5728\u65b0\u7684\u6d41\u4e2d\uff0c\u5426\u5219\u4e0d\u5305\u542b\u3002<\/p>\n
          \u76f8\u5bf9\u5e94\u7684\u8fd8\u6709collect()\u65b9\u6cd5<\/code>\uff0c\u5982\u4e0a\u4f8b\u5b50\u8fd8\u53ef\u4ee5\u8fd9\u6837\u5199\uff1a.filter(n -> n % 2 == 0).collect(Collectors.toList());<\/code>\uff0c\u4f7f\u7528filter()\u65b9\u6cd5<\/code>\u7b5b\u9009\u51fa\u7b26\u5408\u6761\u4ef6\uff08\u5373\u80fd\u88ab2\u6574\u9664\uff09\u7684\u5143\u7d20\uff0c\u6700\u540e\u4f7f\u7528collect()\u65b9\u6cd5\u5c06\u7ed3\u679c\u6536\u96c6\u5230\u4e00\u4e2a\u65b0\u7684List\u4e2d\u3002\n<\/p><\/blockquote>\n
        \u5f53\u52a0\u4e0a\u4e86.max()\u65b9\u6cd5<\/code>\u540e\uff0c\u6d41\u6c34\u7ebf\u5c31\u5b8c\u6574\u4e86\uff0c\u518d\u6b21\u542f\u52a8\uff0c\u5c31\u80fd\u8f93\u51fa\u6240\u6709\u7684filter<\/code>\u6253\u5370\u8bed\u53e5
        \n
        \"image-20240226175434410\"<\/div><\/p>\n
        \u603b\u7ed3\uff1a<\/strong><\/p>\n
          \n
        1. \u6d41\u662f\u60f0\u6027\u7684\uff0c\u5982\uff0c\u751f\u6d3b\u4e2d\u6d41\u6c34\u7ebf\u5b8c\u6574\u4e86\u624d\u4f1a\u542f\u52a8\u4f20\u9001\u5e26\u3002<\/li>\n
        2. \u6d41\u7ba1\u9053\u7ec4\u6210\uff1a\u4e00\u4e2a\u6570\u636e\u6e90\u3001N\u4e2a\u4e2d\u95f4\u64cd\u4f5c\uff08N\u53ef\u4ee5\u4e3a0\uff09\u3001\u4e00\u4e2a\u7ec8\u6b62\u64cd\u4f5c\u3002<\/li>\n<\/ol>\n
          \n
          StreamAPI\u7684\u57fa\u672c\u4f7f\u7528<\/h2>\n
          \u4e00\u3001\u521b\u5efa\u6d41\uff1a<\/strong><\/p>\n
          \"image-20240227173051049\"<\/div><\/p>\n
          \u53ef\u4ee5\u76f4\u63a5\u521b\u5efa\u6d41\uff1a<\/p>\n
                  \/\/1\u3001\u76f4\u63a5\u521b\u5efa\u6d41\uff1a\n        \/\/\u521b\u5efa\u4e86\u4e00\u4e2a\u5305\u542b\u6574\u65701\u30012\u548c3\u7684\u6d41\n        Stream<Integer> stream = Stream.of(1, 2, 3);\n\n        \/\/ \u4f7f\u7528Stream.concat()\u65b9\u6cd5\u5c06\u4e24\u4e2a\u6d41\u8fde\u63a5\u8d77\u6765\uff0c\u521b\u5efa\u4e86\u4e00\u4e2a\u5305\u542b\u6574\u65704\u30015\u30016\u4ee5\u53ca\u4e4b\u524d\u6d41\u4e2d\u7684\u6574\u65701\u30012\u30013\u7684\u65b0\u6d41\n        Stream<Integer> concat = Stream.concat(Stream.of(4, 5, 6), stream);\n\n        \/\/\u4f7f\u7528\u4e86Stream.builder()\u521b\u5efa\u4e86\u4e00\u4e2a\u6d41\u6784\u5efa\u5668\uff0c\u7136\u540e\u6dfb\u52a0\u4e86\u4e24\u4e2a\u5b57\u7b26\u4e32\"11\"\u548c\"22\"\uff0c\u6700\u540e\u901a\u8fc7build()\u65b9\u6cd5\u6784\u5efa\u4e86\u4e00\u4e2a\u5305\u542b\u8fd9\u4e24\u4e2a\u5b57\u7b26\u4e32\u7684\u6d41\n        Stream<Object> build = Stream.builder().add(\"11\").add(\"22\").build();\n<\/code><\/pre>\n
          \u4e5f\u53ef\u4ee5\u96c6\u5408\u5bb9\u5668\u4e2d\u83b7\u53d6\u8fd9\u4e2a\u6d41<\/p>\n
                  \/\/2\u3001\u4ece\u96c6\u5408\u5bb9\u5668\u4e2d\u83b7\u53d6\u8fd9\u4e2a\u6d41\uff0cList\u3001Set\u3001Map\n        List<Integer> list1 = List.of(1, 2);\n        Stream<Integer> stream1 = list1.stream();\n\n        Set<Integer> integers1 = Set.of(1, 2);\n        integers1.stream();\n\n        Map<Object, Object> map = Map.of();\n        map.keySet().stream();\n        map.values().stream();\n<\/code><\/pre>\n
          map\u6709Key\u6709Value\uff0c\u53ef\u4ee5\u5206\u522b\u62ff\u8fd9\u4e24\u4e2a\u7684Stream\u6d41\u3002<\/p>\n
          \n
          \u4e2d\u95f4\u64cd\u4f5c\uff1a<\/strong><\/p>\n
          \"image-20240227175647602\"<\/div><\/p>\n
          \u6d41\u91cf\u5e76\u53d1\u8fd8\u662f\u4e0d\u5e76\u53d1\uff1f\u548cfor\u6709\u4ec0\u4e48\u533a\u522b\uff1f<\/strong><\/p>\n
          \u8981\u9a8c\u8bc1\u8fd9\u4e2a\u95ee\u9898\uff0c\u53ef\u4ee5\u901a\u8fc7\u4ee3\u7801\u6765\u6d4b\u8bd5\u4e00\u4e0b\uff1a<\/p>\n
          System.out.println(\"\u4e3b\u7ebf\u7a0b\uff1a \" + Thread.currentThread());\n        \/\/ \u6d41\u91cf\u5e76\u53d1\u8fd8\u662f\u4e0d\u5e76\u53d1\uff1f\u548cfor\u6709\u4ec0\u4e48\u533a\u522b\uff1f\n        long count = Stream.of(1,2,3,4,5)\n                .filter(i -> {\n                    System.out.println(\"filter\u7ebf\u7a0b\uff1a\" + Thread.currentThread());\n                    System.out.println(\"\u6b63\u5728filter\uff1a\" + i);\n                    return i > 2;\n                }) \/\/ intermediate operation. \u4e2d\u95f4\u64cd\u4f5c\n                .count();   \/\/terminal operation.\u7ec8\u6b62\u64cd\u4f5c\n<\/code><\/pre>\n
          \u8fd0\u884c\u7ed3\u679c\uff1a
          \n
          \"image-20240228113939703\"<\/div><\/p>\n
          \u53ef\u4ee5\u770b\u5230\uff0c\u4e3b\u7ebf\u7a0b\u548cfilter\u7ebf\u7a0b\u662f\u540c\u4e00\u4e2a\uff0c\u8bf4\u660e\u6d41\u4e5f\u662f\u7528for\u5faa\u73af\u6328\u4e2a\u5904\u7406\u7684<\/strong>\u3002<\/p>\n
          \u4f46\u662f\uff01<\/strong>\u6d41\u6709\u4e00\u4e2a\u5f88\u5e05\u7684\u6548\u679c\uff1a\u53ef\u4ee5\u5e76\u53d1<\/strong>\u3002.parallel()<\/code>\u65b9\u6cd5\u3002
          \n\u5728\u6d41\u7684\u540e\u9762\u8c03\u7528\u4e00\u4e0b.parallel()<\/code>\u65b9\u6cd5\uff0c\u5c31\u4f1a\u5e76\u53d1\u6267\u884c<\/p>\n
                  System.out.println(\"\u4e3b\u7ebf\u7a0b\uff1a \" + Thread.currentThread());\n        \/\/ \u6d41\u91cf\u5e76\u53d1\u8fd8\u662f\u4e0d\u5e76\u53d1\uff1f\u548cfor\u6709\u4ec0\u4e48\u533a\u522b\uff1f\n        long count = Stream.of(1,2,3,4,5)\n                .parallel()\n                .filter(i -> {\n                    System.out.println(\"filter\u7ebf\u7a0b\uff1a\" + Thread.currentThread());\n                    System.out.println(\"\u6b63\u5728filter\uff1a\" + i);\n                    return i > 2;\n                }) \/\/ intermediate operation. \u4e2d\u95f4\u64cd\u4f5c\n                .count();   \/\/terminal operation.\u7ec8\u6b62\u64cd\u4f5c\n    }\n<\/code><\/pre>\n
          \u8fd0\u884c\u7ed3\u679c\uff1a
          \n
          \"image-20240228135254429\"<\/div><\/p>\n
          \u8fd9\u65f6\u5019\u53ef\u4ee5\u770b\u5230\uff0c\u53ea\u6709\u4e00\u4e2a\u7ebf\u7a0b\u7684\u540d\u5b57\u662f\u8ddf\u4e3b\u7ebf\u7a0b\u662f\u4e00\u6837\u7684\u3002\u800c\u4e14\u4e5f\u4e0d\u662f\u6309\u987a\u5e8f\u6267\u884c\u7684\u3002\u8bf4\u660e\u8fd9\u662f\u4e2a\u5e76\u53d1\u7684\u8fc7\u7a0b\u3002<\/p>\n
          \u6d41\u9ed8\u8ba4\u662f\u4e0d\u5e76\u53d1<\/strong>\u7684\uff0c\u4f46\u4e5f\u53ef\u4ee5\u5e76\u53d1<\/strong>\u3002\u4f46\u53ea\u8981\u52a0\u4e0a\u4e86.parallel()<\/code>\u65b9\u6cd5\uff0c\u5c31\u4f1a\u53d8\u6210\u4e00\u4e2a\u5e76\u53d1\u6d41\u3002
          \n\u5e76\u53d1\u4ee5\u540e\uff0c\u8981\u81ea\u884c\u89e3\u51b3<\/strong>\u5e76\u53d1\u5b89\u5168\u95ee\u9898\u3002<\/p>\n
          \u4ec0\u4e48\u662f\u5e76\u53d1\u5b89\u5168\u95ee\u9898\u5462\uff1f\u770b\u4e00\u4e0b\u4e0b\u9762\u7684\u4f8b\u5b50\uff1a<\/p>\n
                  List testList = new ArrayList<>();\n        \/\/ \u6d41\u91cf\u5e76\u53d1\u8fd8\u662f\u4e0d\u5e76\u53d1\uff1f\u548cfor\u6709\u4ec0\u4e48\u533a\u522b\uff1f\n        long count = Stream.of(1,2,3,4,5)\n                .parallel()\n                .filter(i -> {\n                    testList.add(i);\n                    return i > 2;\n                }) \/\/ intermediate operation. \u4e2d\u95f4\u64cd\u4f5c\n                .count();   \/\/terminal operation.\u7ec8\u6b62\u64cd\u4f5c\n<\/code><\/pre>\n
          \u5047\u8bbe\u7ebf\u7a0b1\u6267\u884c\u4e86\u4e4b\u540e\uff0ctestList\u5c31\u4f1a\u53d8\u6210\u4e86[1]<\/code>\uff0c
          \n\u8fd9\u4e2a\u65f6\u5019\uff0c\u7ebf\u7a0b2\u548c\u7ebf\u7a0b3\u540c\u65f6\u6267\u884c\uff0c\u90a3\u4e48testList\u5c31\u4f1a\u5206\u522b\u53d8\u6210\uff1a\u7ebf\u7a0b2\uff1a[1,2]\uff0c\u7ebf\u7a0b3\uff1a[1,3]<\/code>\u3002
          \nadd\u4e863\u4e2a\u6570\uff0c\u6b63\u786e\u7684testList\u5e94\u8be5\u662f[1,2,3]<\/code>\u7684\uff0c\u4f46\u662f\u56e0\u4e3a\u5e76\u53d1\u7684\u95ee\u9898\uff0c\u5206\u522b\u53d8\u6210\u4e86\u4e24\u4e2a\u4e0d\u540c\u7684\u5217\u8868\u3002
          \n\u90a3\u4e48\u63a5\u4e0b\u6765\u7ebf\u7a0b4\u6267\u884c\u7684\u65f6\u5019\uff0c\u662f\u8be5\u62ff[1,2]<\/code>\u8fd8\u662f[1,3]<\/code>\u5462\uff1f\u8fd9\u65f6\u5019\u5c31\u51fa\u95ee\u9898\u4e86\u3002<\/p>\n
          \u6d41\u7684\u6240\u6709\u64cd\u4f5c\u90fd\u662f\u65e0\u72b6\u6001<\/strong>\uff0c\u5c31\u662f\u8bf4\uff0c\u6d41\u7684\u6570\u636e\u72b6\u6001\u4ec5\u5728\u672c\u6b21\u6d41\u6709\u6548\uff0c\u4e0d\u6ea2\u51fa\u81f3\u51fd\u6570\u5916<\/strong>\u3002<\/p>\n
          \u6211\u53ef\u4ee5\u5728\u6d41\u4e2d\u5904\u7406\u5b8c\u6570\u636e\u540e\u628a\u6570\u636e\u4ea4\u7ed9\u522b\u4eba\uff0c\u4f46\u662f\u4e0d\u80fd\u5728\u5904\u7406\u7684\u65f6\u5019\u8ba9\u522b\u4eba\u5e2e\u6211\u5b58\u3002<\/p>\n
          \u5728\u5199\u6d41\u7684\u65f6\u5019\uff0c\u8981\u628a\u6d41<\/strong>\u5199\u6210\u4e00\u4e2a\u6574\u4f53<\/strong>\uff0c\u5916\u9762<\/strong>\u7684\u5bb9\u5668\u4e0d\u80fd<\/strong>\u5bf9\u6d41\u91cc\u7684\u4efb\u4f55\u6570\u636e\u6709\u4efb\u4f55\u7684\u5f15\u7528\u3001\u5b58\u50a8\u3001\u589e\u5220\u6539<\/strong>\u3002<\/p>\n
          \u4e0a\u9762\u7684\u95ee\u9898\u53ef\u4ee5\u7528\u9501\u6765\u89e3\u51b3\uff1a<\/p>\n
                  System.out.println(\"\u4e3b\u7ebf\u7a0b\uff1a \" + Thread.currentThread());\n\n        List testList = new ArrayList<>();\n        \/\/ \u6d41\u91cf\u5e76\u53d1\u8fd8\u662f\u4e0d\u5e76\u53d1\uff1f\u548cfor\u6709\u4ec0\u4e48\u533a\u522b\uff1f\n        long count = Stream.of(1,2,3,4,5)\n                .parallel()\n                .filter(i -> {\n                    synchronized (Object.class){\n                        System.out.println(\"filter\u7ebf\u7a0b\uff1a\" + Thread.currentThread());\n                        System.out.println(\"\u6b63\u5728filter\uff1a\" + i);\n                        testList.add(i);\n                        System.out.println(\"testList\uff1a\" + testList);\n                        return i > 2;\n                    }\n                }) \/\/ intermediate operation. \u4e2d\u95f4\u64cd\u4f5c\n                .count();   \/\/terminal operation.\u7ec8\u6b62\u64cd\u4f5c\n<\/code><\/pre>\n
          \u6267\u884c\u7ed3\u679c\uff1a
          \n
          \"image-20240228144318704\"<\/div><\/p>\n
          \u4f46\u662f\u7528\u9501\u4e4b\u540e\u5c31\u4e32\u884c\u4e86\uff0c\u8ddf\u4e4b\u524d\u7684\u4e0d\u7528.parallel()<\/code>\u65b9\u6cd5\u662f\u7c7b\u4f3c\u7684\u6267\u884c\u8fc7\u7a0b\uff0c\u6240\u4ee5\u4e5f\u76f8\u5f53\u4e8e\u6ca1\u6709\u5e76\u53d1\u3002<\/p>\n
          \n  synchronized\u53ef\u4ee5\u63a7\u5236\u5e76\u53d1\u3002\u7c7b\u4f3c\u4e00\u628a\u7410\uff0c\u6240\u6709\u7684\u7ebf\u7a0b\u53bb\u62a2\u8fd9\u628a\u9501\uff0c\u8c01\u5148\u62ff\u5230\u9501\u8c01\u5c31\u5148\u6267\u884c\u3002\n<\/p><\/blockquote>\n
          \u603b\u7ed3\uff1a<\/p>\n
          \u5982\u679c\u8981\u7528\u5e76\u53d1<\/strong>\uff0c\u5c31\u8981\u660e\u786e<\/strong>\u6d41\u91cc\u9762\u4e0d\u4f1a\u4ea7\u751f\u95ee\u9898\uff0c\u662f\u5b89\u5168\u7684<\/strong>\u3002\u5982\u679c\u53ef\u80fd\u4f1a\u51fa\u73b0\u95ee\u9898\uff0c\u5c31\u4e0d\u8981\u7528\u5e76\u53d1\u3002
          \n\u5982\u679c\u7528\u4e86\u5e76\u53d1\uff0c\u4e14\u51fa\u73b0\u95ee\u9898<\/strong>\u4e86\uff0c\u53ef\u4ee5\u7528\u9501\u89e3\u51b3<\/strong>\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"
          \u5f15\u5165 Stream\u5c31\u662f\u6d41\uff0c\u6d41\u5f0f\u64cd\u4f5c\u5c31\u8ddf\u751f\u6d3b\u4e2d\u7684\u6d41\u6c34\u7ebf\u4e00\u6837\u3002\u6bd4\u5982\u6211\u6709\u4e00\u6279\u539f\u6750\u6599\uff0c\u7ecf\u8fc7\u6d41\u6c34\u7ebf \u6311\u9009–> […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[95],"tags":[98],"class_list":["post-515","post","type-post","status-publish","format-standard","hentry","category-reactive","tag-streamapi"],"_links":{"self":[{"href":"https:\/\/pidanxia.ink\/wp-json\/wp\/v2\/posts\/515","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/pidanxia.ink\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/pidanxia.ink\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/pidanxia.ink\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/pidanxia.ink\/wp-json\/wp\/v2\/comments?post=515"}],"version-history":[{"count":2,"href":"https:\/\/pidanxia.ink\/wp-json\/wp\/v2\/posts\/515\/revisions"}],"predecessor-version":[{"id":517,"href":"https:\/\/pidanxia.ink\/wp-json\/wp\/v2\/posts\/515\/revisions\/517"}],"wp:attachment":[{"href":"https:\/\/pidanxia.ink\/wp-json\/wp\/v2\/media?parent=515"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/pidanxia.ink\/wp-json\/wp\/v2\/categories?post=515"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/pidanxia.ink\/wp-json\/wp\/v2\/tags?post=515"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}