{"id":1586,"date":"2020-11-19T11:25:00","date_gmt":"2020-11-19T03:25:00","guid":{"rendered":"https:\/\/www.yusian.com\/blog\/?p=1586"},"modified":"2020-11-26T20:23:40","modified_gmt":"2020-11-26T12:23:40","slug":"java%e5%86%85%e7%bd%ae%e7%9a%84%e5%87%a0%e4%b8%aa%e5%87%bd%e6%95%b0%e5%bc%8f%e6%8e%a5%e5%8f%a3%e7%9a%84%e5%9f%ba%e6%9c%ac%e4%bd%bf%e7%94%a8","status":"publish","type":"post","link":"https:\/\/www.yusian.com\/blog\/java\/2020\/11\/19\/1125001586.html","title":{"rendered":"Java\u5185\u7f6e\u7684\u51e0\u4e2a\u51fd\u6570\u5f0f\u63a5\u53e3\u7684\u57fa\u672c\u4f7f\u7528"},"content":{"rendered":"
    \n
  1. \u76f8\u5173\u7c7b\uff1aSupplier<\/code>\u3001Consumer<\/code>\u3001Predicate<\/code>\u3001Function<\/code><\/strong><\/p>\n<\/li>\n
  2. \n

    \u4ec0\u4e48\u662f\u51fd\u6570\u5f0f\u63a5\u53e3<\/p>\n

      \n
    • \u6709\u4e14\u53ea\u6709\u4e00\u4e2a\u62bd\u8c61\u65b9\u6cd5\u7684\u63a5\u53e3\u88ab\u79f0\u4f5c\u51fd\u6570\u5f0f\u63a5\u53e3<\/li>\n
    • \u51fd\u6570\u5f0f\u63a5\u53e3\u53ef\u4ee5\u76f4\u63a5\u5199\u6210Lambda\u8868\u8fbe\u5f0f<\/li>\n
    • \u51fd\u6570\u5f0f\u63a5\u53e3\u8fd8\u53ef\u4ee5\u5199\u6210\u65b9\u6cd5\u5f15\u7528\u7684\u65b9\u5f0f<\/li>\n
    • \u51fd\u6570\u5f0f\u63a5\u53e3\u5bf9\u5916\u5c55\u793a\u7684\u662f\u4e00\u4e2a\u89c4\u8303\uff0c\u53ea\u9700\u8981\u6ee1\u8db3\u8fd9\u79cd\u89c4\u8303\u5373\u53ef\u6210\u4e3a\u5176\u5b9e\u73b0<\/li>\n
    • \u51fd\u6570\u5f0f\u63a5\u53e3\u53ef\u4ee5\u7c7b\u6bd4\u4e3a\u591a\u6001\u5728\u51fd\u6570\u5f0f\u7ed3\u6784\u4e0a\u7684\u5b9e\u73b0<\/li>\n<\/ul>\n
      package com.yusian.function;\n\nimport java.util.function.Supplier;\n\n\/**\n* Supplier\u662f\u4e00\u4e2a\u51fd\u6570\u5f0f\u63a5\u53e3\uff0c\u8fd4\u56de\u4efb\u610f\u7c7b\u578b\u6570\u636e\uff0c\u662f\u4e00\u4e2a\u5bb9\u5668\n* \u4ed6\u662f\u5bf9\u6240\u6709\u65e0\u53c2\u5e76\u8fd4\u56de\u4e00\u4e2a\u5bf9\u8c61\u7684\u7ed3\u6784\u62bd\u8c61\uff0c\u4e00\u5207\u65e0\u53c2\u5e76\u8fd4\u56de\u5bf9\u8c61\u7684\u65b9\u6cd5\u90fd\u53ef\u4ee5\u6210\u4e3a\u4ed6\u7684\u5b9e\u73b0\n* \u8fd9\u4f7f\u5f97\u7f16\u7a0b\u53d8\u5f97\u66f4\u52a0\u5f00\u653e\uff0c\u53ef\u4ee5\u60f3\u50cf\u662f\u591a\u6001\u5728\u51fd\u6570\u5f0f\u7f16\u7a0b\u65b9\u5f0f\u4e0a\u7684\u5b9e\u73b0\n*\/\npublic class SupplierDemo {\n\n   public static void main(String[] args) {\n       \/\/ 1\u3001\u533f\u540d\u5185\u90e8\u7c7b\n       Supplier<Person> sup1 = new Supplier<Person>() {\n           @Override\n           public Person get() {\n               return new Person();\n           }\n       };\n       Person p1 = sup1.get();\n\n       \/\/ 2\u3001Lambda\u8868\u8fbe\u5f0f\n       Supplier<Person> sup2 = () -> new Person();\n       Person p2 = sup2.get();\n\n       \/\/ 3\u3001\u65b9\u6cd5\u5f15\u7528\n       Supplier<Person> sup3 = Person::new;\n       Person p3 = sup3.get();\n\n       \/\/ 4\u3001\u672c\u5730\u65b9\u6cd5\u6a21\u62df\n       Person p4 = supplier();\n\n       \/\/ 5\u3001\u53ea\u8981\u6ee1\u8db3\u51fd\u6570\u5f0f\u7ed3\u6784\u5c31\u53ef\u4ee5\n       Supplier<Person> sup5 = SupplierDemo::supplier;\n       Person p5 = sup5.get();\n\n       System.out.println(p1);\n       System.out.println(p2);\n       System.out.println(p3);\n       System.out.println(p4);\n       System.out.println(p5);\n   }\n\n   \/**\n    * \u83b7\u53d6\u4e00\u4e2aPerson\u5b9e\u4f8b\u5bf9\u8c61\n    * @return Person\n    *\/\n   public static Person supplier() {\n       return new Person();\n   }\n}\n<\/code><\/pre>\n
      <\/li>\n
    • \u5185\u7f6e\u51fd\u6570\u5f0f\u63a5\u53e3\u7684\u5e94\u7528<\/li>\n<\/ol>\n
        \n
      • Supplier<\/code>\uff1a\u63d0\u4f9b\u8005\uff0c\u8be5\u63a5\u53e3\u8fd4\u56de\u4e00\u4e2a\u5bf9\u8c61\uff0c\u4ee5\u4efb\u4f55\u65b9\u5f0f\u53ca\u4efb\u4f55\u8eab\u4efd\u8fd4\u56de\u4e00\u4e2a\u5bf9\u8c61\uff0c\u53ea\u8981\u662f\u65e0\u53c2\u6570\u8fd4\u56de\u4e00\u4e2a\u5bf9\u8c61\u7684\u4efb\u4f55\u65b9\u6cd5\u90fd\u53ef\u4ee5\u6210\u4e3a\u5176\u5b9e\u73b0\uff1b<\/p>\n<\/li>\n
      • \n
        Consumer<\/code>\uff1a\u6d88\u8d39\u8005\uff0c\u4f20\u5165\u4e00\u4e2a\u5bf9\u8c61\u65e0\u8fd4\u56de\u503c\uff0c\u63d0\u4f9b\u4e00\u4e2a\u5bf9\u8c61\uff0c\u53ef\u4ee5\u662f\u4efb\u4f55\u5f62\u5f0f\u7684\u8c03\u7528\uff0c\u201c\u5c3d\u60c5\u6d88\u8d39\u201d\uff1b<\/p>\n
        Consumer<\/code>\u4e2d\u6709\u4e00\u4e2aandThen<\/code>\u65b9\u6cd5\uff0c\u8fd9\u4e2a\u65b9\u6cd5\u4f1a\u8fd4\u56de\u4e00\u4e2aConsumer<\/code>\uff0c\u6709\u70b9\u7ed5<\/p>\n
         package com.yusian.function;\n\n import java.util.function.Consumer;\n\n public class ConsumerDemo {\n     public static void main(String[] args) {\n         \/*\n          * \u8f93\u51fa\u7ed3\u679c\u4e3a\uff1a\n          * Hello World\n          * Hello World-1\n          * Hello World-2\n          *\/\n         Consumer<String> con = System.out::println;\n         con.andThen(str -> {\n             System.out.println(str + \"-1\");\n         }).andThen(str -> {\n             System.out.println(str + \"-2\");\n         }).accept(\"Hello World\");\n\n         \/*\n          * \u6362\u4e2a\u5f62\u5f0f\u6765\u89e3\u91ca\uff1a\n          * con1\u8c03\u7528andThen\u65b9\u6cd5\uff0ccon2\u4e3a\u53c2\u6570\u5f97\u5230\u7684\u7ed3\u679c\u662f\u4e00\u4e2aConsumer\n          * \u5f97\u5230\u7684\u8fd9\u4e2aConsumer\u5373\u4e0d\u662fcon1\u4e5f\u4e0d\u662fcon2\uff0c\u662f\u4e00\u4e2a\u4f1a\u5148\u6267\u884ccon1\u7684accept\u65b9\u6cd5\u518d\u6267\u884ccon2\u7684\n          * accept\u65b9\u6cd5\u7684Consumer\n          * \u53ef\u4ee5\u7b80\u5355\u7684\u7406\u89e3\u4e3a\u8fd4\u56de\u7684\u8fd9\u4e2aConsumer\u4e2daccept\u65b9\u6cd5\u662f\u5c06con1\u548ccon2\u7684accept\u65b9\u6cd5\u6309\u5148\u540e\u987a\u5e8f\n          * \u8c03\u7528\n          * \u540c\u7406\uff1a\u518d\u8c03\u7528andThen\u65b9\u6cd5\u662f\u65b0\u8fd9\u4e2a\u65b0\u7684Consumer\u8c03\u7528\u7684\uff0c\u518d\u5c06con3\u62c9\u8fdb\u6765\u8fd4\u56de\u4e00\u4e2a\u65b0\u7684                \n          * Consumer\n          * \u4ece\u8868\u9762\u4e0a\u770b\u4e00\u5171\u662f\u5b9a\u4e49\u4e864\u4e2aConsumer\uff0c\u73b0\u5b9e\u4e0a\u4e00\u5171\u51fa\u73b0\u7684Consumer\u67097\u4e2a\uff0c\u6bcf\u8c03\u7528\u4e00\u6b21andThen\n          * \u90fd\u4f1a\u751f\u6210\u4e00\u4e2a\u65b0\u7684Consumer\n          *\/\n         Consumer<String> con1 = str -> System.out.println(str + \"-1\");\n         Consumer<String> con2 = str -> System.out.println(str + \"-2\");\n         Consumer<String> con3 = str -> System.out.println(str + \"-3\");\n         Consumer<String> con4 = str -> System.out.println(str + \"-4\");\n         con1.andThen(con2).andThen(con3).andThen(con4).accept(\"Java\");\n     }\n }\n ```\n \u6267\u884c\u7ed3\u679c\uff1a\n\n```cmd\n Hello World\nHello World-1\n Hello World-2\n Java-1\n Java-2\n Java-3\n Java-4\n<\/code><\/pre>\n<\/li>\n
      • Predicate<\/code>\uff1a\u65ad\u8a00\uff0c\u7528\u4e8e\u5bf9\u4f20\u5165\u5bf9\u8c61\u7684boolean\u5224\u65ad\uff0c\u7ed9\u4f60\u4e00\u4e2a\u5bf9\u8c61\uff0c\u4f60\u544a\u8bc9\u6211\u662f\u5426\uff1b\n
         package com.yusian.function;\n\n import java.util.ArrayList;\n import java.util.function.Predicate;\n\n public class PredicateDemo {\n     public static void main(String[] args) {\n         demo01();\n     }\n\n     \/\/ \u8fc7\u6ee4\u5b57\u7b26\u4e32\u6570\u7ec4\u4e2d\u7684\u7279\u5b9a\u5143\u7d20\uff0c2\u4e2a\u8fc7\u6ee4\u6761\u4ef6\u53ef\u4ee5\u901a\u8fc72\u4e2aPredicate\u5b9e\u73b0\n     private static void demo01() {\n         \/\/ \u8fc7\u6ee4\u6570\u7ec4\n         String[] array = {\"xxxx,\u5973\", \"yyyy,\u5973\", \"zzzz,\u7537\", \"xxx,\u5973\"};\n         ArrayList<String> list = new ArrayList<>();\n         Predicate<String> pre1 = str -> str.split(\",\")[0].length() == 4;\n         Predicate<String> pre2 = str -> str.split(\",\")[1].equals(\"\u5973\");\n         for (String s : array) {\n             if (filter(s, pre1, pre2)) list.add(s);\n         }\n         System.out.println(list);\n     }\n\n     private static boolean filter(String str, Predicate<String> pre1, Predicate<String> pre2) {\n         return pre1.and(pre2).test(str);\n     }\n\n     private static void basic() {\n\n         Predicate<String> pre1 = str -> str.endsWith(\"s\");\n         Predicate<String> pre2 = str -> str.length() > 3;\n\n         boolean b1 = pre1.test(\"yes\");\n         System.out.println(b1);\n\n         \/\/ or\u65b9\u6cd5\u8fd4\u56de\u7684\u662f\u4e00\u4e2a\u65b0\u7684Predicate\uff0c\u8fd9\u4e2aPredicate\u5c06\u524d\u4e00\u4e2aPredicate\u4e0e\u4f20\u5165\u7684\u8fd9\u4e2aPredicate\u4e2d\u7684\u4e24\u4e2atest\u65b9\u6cd5\u8fdb\u884c\u6216\u8fd0\u7b97\n         boolean b2 = pre1.or(pre2).test(\"think\");\n         System.out.println(b2);\n\n         \/\/ and\u65b9\u6cd5\u8fd4\u56de\u7684\u662f\u4e00\u4e2a\u65b0\u7684Predicate\uff0c\u8fd9\u4e2aPredicate\u5c06\u524d\u4e00\u4e2aPredicate\u4e0e\u4f20\u5165\u7684\u8fd9\u4e2aPredicate\u4e2d\u7684\u4e24\u4e2atest\u65b9\u6cd5\u8fdb\u884c\u4e0e\u8fd0\u7b97\n         boolean b3 = pre1.and(pre2).test(\"this\");\n         System.out.println(b3);\n\n         \/\/ negate\u65b9\u6cd5\u8fd4\u56de\u4e00\u4e2a\u65b0\u7684Predicate\uff0c\u8fd9\u4e2aPredicate\u7684test\u65b9\u6cd5\u662f\u5bf9\u8c03\u7528\u8005\u7684test\u65b9\u6cd5\u53d6\u53cd\n         boolean b4 = pre1.negate().test(\"yes\");\n         System.out.println(b4);\n\n         \/\/ equal\u65b9\u6cd5\u53ea\u662f\u7b80\u5355\u7684==\u8fd0\u7b97\uff0c\u53ef\u80fd\u662f\u4e3a\u4e86\u5145\u5b9e\u8fd9\u4e2a\u63a5\u53e3\u7684\u529f\u80fd\u5427\n         boolean b5 = pre1.equals(pre2);\n         System.out.println(b5);\n     }\n }\n<\/code><\/pre>\n<\/li>\n
      • Function<\/code>\uff1a\u529f\u80fd\n
         package com.yusian.function;\n\n import java.util.function.Function;\n\n public class FunctionDemo {\n     public static void main(String[] args) {\n         \/\/ \u5c06\u5b57\u7b26\u4e32\u62fc\u63a5\"10\"\u518d\u8f6c\u6210\u6570\u5b57\n         Function<String, Integer> fun1 = str -> Integer.parseInt(str + \"10\");\n         \/\/ \u5c06\u6570\u5b57+10\u518d\u8f6c\u6210\u5b57\u7b26\u4e32\n         Function<Integer, String> fun2 = n -> String.valueOf(n + 10);\n\n         \/\/ andThen\u4f1a\u6267\u884c\u524d\u9762\u7684Function\u7684apply\uff0c\u6240\u4ee5\u662f12310+10 \u6570\u5b5712320\n         String ret1 = fun1.andThen(fun2).apply(\"123\");\n         System.out.println(ret1);\n\n         \/\/ compose\u4f1a\u5148\u6267\u884c\u540e\u9762Function\u7684apply\uff0c\u6240\u4ee5\u662f133\u62fc\u63a5\"10\" \u5b57\u7b26\u4e3213310\n         Integer ret2 = fun1.compose(fun2).apply(123);\n         System.out.println(ret2);\n     }\n }\n<\/code><\/pre>\n<\/li>\n<\/ul>\n","protected":false},"excerpt":{"rendered":"
        \u76f8\u5173\u7c7b\uff1aSupplier\u3001Consumer\u3001Predicate\u3001Function \u4ec0\u4e48\u662f\u51fd\u6570\u5f0f\u63a5\u53e3 \u6709\u4e14\u53ea\u6709\u4e00\u4e2a\u62bd\u8c61\u65b9\u6cd5\u7684\u63a5\u53e3\u88ab\u79f0\u4f5c\u51fd\u6570\u5f0f\u63a5\u53e3 \u51fd\u6570\u5f0f\u63a5\u53e3\u53ef\u4ee5\u76f4\u63a5\u5199\u6210Lambda\u8868\u8fbe\u5f0f \u51fd\u6570\u5f0f\u63a5\u53e3\u8fd8\u53ef\u4ee5\u5199\u6210\u65b9\u6cd5\u5f15\u7528\u7684\u65b9\u5f0f \u51fd\u6570\u5f0f\u63a5\u53e3\u5bf9\u5916\u5c55\u793a\u7684\u662f\u4e00\u4e2a\u89c4\u8303\uff0c\u53ea\u9700\u8981\u6ee1\u8db3\u8fd9\u79cd\u89c4\u8303\u5373\u53ef\u6210\u4e3a\u5176\u5b9e\u73b0 \u51fd\u6570\u5f0f\u63a5\u53e3\u53ef\u4ee5\u7c7b\u6bd4\u4e3a\u591a\u6001\u5728\u51fd\u6570\u5f0f\u7ed3\u6784\u4e0a\u7684\u5b9e\u73b0 package com.yusian.function; import java.util.function.Supplier; \/** * Supplier\u662f\u4e00\u4e2a\u51fd\u6570\u5f0f\u63a5\u53e3\uff0c\u8fd4\u56de\u4efb\u610f\u7c7b\u578b\u6570\u636e\uff0c\u662f\u4e00\u4e2a\u5bb9\u5668 * \u4ed6\u662f\u5bf9\u6240\u6709\u65e0\u53c2\u5e76\u8fd4\u56de\u4e00\u4e2a\u5bf9\u8c61\u7684\u7ed3\u6784\u62bd\u8c61\uff0c\u4e00\u5207\u65e0\u53c2\u5e76\u8fd4\u56de\u5bf9\u8c61\u7684\u65b9\u6cd5\u90fd\u53ef\u4ee5\u6210\u4e3a\u4ed6\u7684\u5b9e\u73b0 * \u8fd9\u4f7f\u5f97\u7f16\u7a0b\u53d8\u5f97\u66f4\u52a0\u5f00\u653e\uff0c\u53ef\u4ee5\u60f3\u50cf\u662f\u591a\u6001\u5728\u51fd\u6570\u5f0f\u7f16\u7a0b\u65b9\u5f0f\u4e0a\u7684\u5b9e\u73b0 *\/ public class SupplierDemo { public static void main(String[] args) { \/\/ 1\u3001\u533f\u540d\u5185\u90e8\u7c7b Supplier<Person> sup1 = new Supplier<Person>() { @Override public Person get() { return new Person(); } }; Person p1 = sup1.get(); \/\/ 2\u3001Lambda\u8868\u8fbe\u5f0f Supplier<Person> sup2 […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[35],"tags":[272,274,273,271,270],"class_list":["post-1586","post","type-post","status-publish","format-standard","hentry","category-java","tag-consumer","tag-function","tag-predicate","tag-supplier","tag-270"],"_links":{"self":[{"href":"https:\/\/www.yusian.com\/blog\/wp-json\/wp\/v2\/posts\/1586","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.yusian.com\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.yusian.com\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.yusian.com\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.yusian.com\/blog\/wp-json\/wp\/v2\/comments?post=1586"}],"version-history":[{"count":0,"href":"https:\/\/www.yusian.com\/blog\/wp-json\/wp\/v2\/posts\/1586\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.yusian.com\/blog\/wp-json\/wp\/v2\/media?parent=1586"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.yusian.com\/blog\/wp-json\/wp\/v2\/categories?post=1586"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.yusian.com\/blog\/wp-json\/wp\/v2\/tags?post=1586"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}