{"id":203053,"date":"2025-05-22T11:27:22","date_gmt":"2025-05-22T03:27:22","guid":{"rendered":"https:\/\/server.hk\/cnblog\/203053\/"},"modified":"2025-05-22T11:27:22","modified_gmt":"2025-05-22T03:27:22","slug":"%e5%a6%82%e4%bd%95%e4%bd%bf%e7%94%a8java-lambda%e8%a1%a8%e8%be%be%e5%bc%8f%e8%bf%87%e6%bb%a4%e9%9b%86%e5%90%88%ef%bc%9f","status":"publish","type":"post","link":"https:\/\/server.hk\/cnblog\/203053\/","title":{"rendered":"\u5982\u4f55\u4f7f\u7528Java lambda\u8868\u8fbe\u5f0f\u8fc7\u6ee4\u96c6\u5408\uff1f"},"content":{"rendered":"

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

\u5982\u4f55\u4f7f\u7528Java lambda\u8868\u8fbe\u5f0f\u8fc7\u6ee4\u96c6\u5408\uff1f<\/h1>\n

\u6765\u5230\u7684\u5927\u5bb6\uff0c\u76f8\u4fe1\u90fd\u662f\u7f16\u7a0b\u5b66\u4e60\u7231\u597d\u8005\uff0c\u5e0c\u671b\u5728\u8fd9\u91cc\u5b66\u4e60\u6587\u7ae0\u76f8\u5173\u7f16\u7a0b\u77e5\u8bc6\u3002\u4e0b\u9762\u672c\u7bc7\u6587\u7ae0\u5c31\u6765\u5e26\u5927\u5bb6\u804a\u804a\u300a\u5982\u4f55\u4f7f\u7528Java lambda\u8868\u8fbe\u5f0f\u8fc7\u6ee4\u96c6\u5408\uff1f\u300b\uff0c\u4ecb\u7ecd\u4e00\u4e0b\uff0c\u5e0c\u671b\u5bf9\u5927\u5bb6\u7684\u77e5\u8bc6\u79ef\u7d2f\u6709\u6240\u5e2e\u52a9\uff0c\u52a9\u529b\u5b9e\u6218\u5f00\u53d1\uff01<\/p>\n

\u4f7f\u7528 Java lambda \u8868\u8fbe\u5f0f\u8fc7\u6ee4\u96c6\u5408\u7684\u65b9\u6cd5\uff1a\u4f7f\u7528 stream() \u521b\u5efa\u96c6\u5408\u7684\u6d41\u3002\u4f7f\u7528 filter() \u65b9\u6cd5\u5e94\u7528 lambda \u8868\u8fbe\u5f0f\u4f5c\u4e3a\u8fc7\u6ee4\u6761\u4ef6\u3002\u4f7f\u7528 toList() \u65b9\u6cd5\u5c06\u8fc7\u6ee4\u540e\u7684\u5143\u7d20\u6536\u96c6\u5230\u65b0\u96c6\u5408\u4e2d\u3002<\/p>\n

<\/p>\n

\u5982\u4f55\u4f7f\u7528 Java lambda \u8868\u8fbe\u5f0f\u8fc7\u6ee4\u96c6\u5408\uff1f<\/h2>\n

\u7b80\u4ecb<\/strong><\/p>\n

lambda \u8868\u8fbe\u5f0f\u662f Java 8 \u4e2d\u5f15\u5165\u7684\u4e00\u79cd\u5f3a\u5927\u529f\u80fd\uff0c\u5b83\u5141\u8bb8\u6211\u4eec\u7528\u7b80\u6d01\u7684\u65b9\u5f0f\u5199\u51fd\u6570\u3002\u4f7f\u7528 lambda \u8868\u8fbe\u5f0f\uff0c\u6211\u4eec\u53ef\u4ee5\u8f7b\u677e\u5730\u8fc7\u6ee4\u96c6\u5408\u4e2d\u6ee1\u8db3\u7279\u5b9a\u6761\u4ef6\u7684\u5143\u7d20\u3002<\/p>\n

\u8bed\u6cd5<\/strong><\/p>\n

lambda \u8868\u8fbe\u5f0f\u7684\u8bed\u6cd5\u5982\u4e0b\uff1a<\/p>\n

(parameters) -> expression<\/pre>\n
\u5176\u4e2d\uff1a<\/p>\n
    \n
  • parameters\uff1alambda \u8868\u8fbe\u5f0f\u7684\u53c2\u6570\uff0c\u7528\u5706\u62ec\u53f7\u62ec\u8d77\u6765\u3002<\/li>\n
  • expression\uff1alambda \u8868\u8fbe\u5f0f\u7684\u6267\u884c\u4f53\uff0c\u7528\u5927\u62ec\u53f7\u6216\u7bad\u5934 (->) \u5206\u9694\u3002<\/li>\n<\/ul>\n
    \u5b9e\u6218\u6848\u4f8b<\/strong><\/p>\n
    \u8ba9\u6211\u4eec\u901a\u8fc7\u4e00\u4e2a\u5b9e\u6218\u6848\u4f8b\u6765\u4e86\u89e3\u5982\u4f55\u4f7f\u7528 lambda \u8868\u8fbe\u5f0f\u8fc7\u6ee4\u96c6\u5408\u3002\u5047\u8bbe\u6211\u4eec\u6709\u4e00\u4e2a List<\/code> \u5305\u542b\u5b57\u7b26\u4e32\uff0c\u73b0\u5728\u6211\u4eec\u60f3\u5c06\u5217\u8868\u4e2d\u4ee5 “a” \u5f00\u5934\u7684\u5b57\u7b26\u4e32\u8fc7\u6ee4\u51fa\u6765\uff1a<\/p>\n
    import java.util.Arrays;\nimport java.util.List;\n\npublic class FilterCollection {\n\n    public static void main(String[] args) {\n        \/\/ \u521b\u5efa\u4e00\u4e2a\u5305\u542b\u5b57\u7b26\u4e32\u7684 List\n        List<String> names = Arrays.asList(\"Alice\", \"Bob\", \"Carol\", \"Dave\", \"Eve\");\n\n        \/\/ \u4f7f\u7528 lambda \u8868\u8fbe\u5f0f\u8fc7\u6ee4 List\n        List<String> filteredNames = names.stream()\n                .filter(name -> name.startsWith(\"A\"))\n                .toList();\n\n        \/\/ \u6253\u5370\u8fc7\u6ee4\u540e\u7684 List\n        System.out.println(filteredNames);\n    }\n}<\/pre>\n
    \u89e3\u91ca<\/strong><\/p>\n
      \n
    • \u6211\u4eec\u4f7f\u7528 stream()<\/code> \u65b9\u6cd5\u521b\u5efa\u5217\u8868\u7684\u6d41\uff0c\u4ee5\u4fbf\u5bf9\u5176\u8fdb\u884c\u64cd\u4f5c\u3002<\/li>\n
    • filter()<\/code> \u65b9\u6cd5\u63a5\u53d7\u4e00\u4e2a lambda \u8868\u8fbe\u5f0f\u4f5c\u4e3a\u53c2\u6570\uff0c\u8be5\u8868\u8fbe\u5f0f\u7528\u4e8e\u6839\u636e\u7279\u5b9a\u6761\u4ef6\u8fc7\u6ee4\u6d41\u4e2d\u7684\u5143\u7d20\u3002\u5728\u8fd9\u4e2a\u4f8b\u5b50\u4e2d\uff0clambda \u8868\u8fbe\u5f0f (name -> name.startsWith(\"A\"))<\/code> \u53ea\u5141\u8bb8\u540d\u79f0\u4ee5 “A” \u5f00\u5934\u7684\u5143\u7d20\u901a\u8fc7\u3002<\/li>\n
    • \u6700\u540e\uff0c\u6211\u4eec\u4f7f\u7528 toList()<\/code> \u65b9\u6cd5\u5c06\u8fc7\u6ee4\u540e\u7684\u5143\u7d20\u6536\u96c6\u5230\u4e00\u4e2a\u65b0\u5217\u8868\u4e2d\u3002<\/li>\n<\/ul>\n
      \u7ed3\u8bba<\/strong><\/p>\n
      lambda \u8868\u8fbe\u5f0f\u662f\u8fc7\u6ee4\u96c6\u5408\u7684\u4e00\u79cd\u7b80\u6d01\u4e14\u5f3a\u5927\u7684\u65b9\u5f0f\u3002\u901a\u8fc7\u4f7f\u7528 lambda \u8868\u8fbe\u5f0f\uff0c\u6211\u4eec\u53ef\u4ee5\u8f7b\u677e\u5730\u5b9a\u4e49\u6761\u4ef6\u6765\u7b5b\u9009\u5143\u7d20\uff0c\u5e76\u521b\u5efa\u4e00\u4e2a\u5305\u542b\u7b26\u5408\u8be5\u6761\u4ef6\u7684\u6240\u6709\u5143\u7d20\u7684\u65b0\u96c6\u5408\u3002<\/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","protected":false},"excerpt":{"rendered":"
      \u5982\u4f55\u4f7f\u7528Java lambda\u8868...<\/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-203053","post","type-post","status-publish","format-standard","hentry","category-4925"],"_links":{"self":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/203053","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=203053"}],"version-history":[{"count":0,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/203053\/revisions"}],"wp:attachment":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/media?parent=203053"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/categories?post=203053"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/tags?post=203053"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}