\u4ee5\u4e0b\u662fJava\u51fd\u6570\u5f0f\u7f16\u7a0b\u4e2dLambda\u4e0eStream API\u7684\u9ad8\u7ea7\u5e94\u7528\u6307\u5357\uff0c\u7ed3\u54082025\u5e74\u6700\u65b0\u6280\u672f\u5b9e\u8df5\uff1a<\/p>\n
\u4e00\u3001Lambda\u8868\u8fbe\u5f0f\u6df1\u5ea6\u4f18\u5316
\u200c\u7c7b\u578b\u63a8\u65ad\u589e\u5f3a\u200c<\/p>\n
\u7701\u7565\u53c2\u6570\u7c7b\u578b\u58f0\u660e\uff0c\u7f16\u8bd1\u5668\u81ea\u52a8\u63a8\u65ad\uff08\u5982(x,y) -> x+y\uff0924
\u5355\u4e2a\u53c2\u6570\u65f6\u53ef\u7701\u7565\u62ec\u53f7\uff1ax -> x*24
\u200c\u65b9\u6cd5\u5f15\u7528\u8fdb\u9636\u200c<\/p>\n
java
Copy Code
\/\/ \u9759\u6001\u65b9\u6cd5\u5f15\u7528
List<Integer> nums = Arrays.asList(1, 2, 3);
nums.forEach(System.out::println); \/\/ \u7b49\u4ef7\u4e8e x -> System.out.println(x):ml-citation{ref=”5,8″ data=”citationList”}
\u200c\u5f02\u5e38\u5904\u7406\u6280\u5de7\u200c<\/p>\n
\u4f7f\u7528Unchecked\u51fd\u6570\u5f0f\u63a5\u53e3\u5305\u88c5\u53d7\u68c0\u5f02\u5e38
java
Copy Code
Function<String, Integer> safeParse = s -> {<\/p>\n
try { return Integer.parseInt(s); }\ncatch (NumberFormatException e) { throw new RuntimeException(e); }<\/code><\/pre>\n};
\u4e8c\u3001Stream API\u9ad8\u9636\u64cd\u4f5c
\u200c\u64cd\u4f5c\u7c7b\u578b\u200c \u200c\u5178\u578b\u573a\u666f\u200c \u200c\u793a\u4f8b\u4ee3\u7801\u200c
\u200c\u5e76\u884c\u6d41\u4f18\u5316\u200c \u5927\u6570\u636e\u96c6\u5904\u7406\u52a0\u901f list.parallelStream().filter(x -> x>0).collect(Collectors.toList()
\u200c\u77ed\u8def\u7ec8\u6b62\u200c \u907f\u514d\u5168\u91cf\u904d\u5386 list.stream().anyMatch(x -> x.contains(“error”))
\u200c\u81ea\u5b9a\u4e49\u6536\u96c6\u5668\u200c \u590d\u6742\u805a\u5408\u903b\u8f91 \u5b9e\u73b0Collector\u63a5\u53e3\u5b9a\u4e49\u5206\u4f4d\u6570\u8ba1\u7b97
\u200c\u5206\u7ec4\u7edf\u8ba1\u9ad8\u7ea7\u793a\u4f8b\u200c\uff1a<\/p>\n
java
Copy Code
Map<Department, Double> avgSalary = employees.stream()<\/p>\n
.collect(Collectors.groupingBy(\n Employee::getDept,\n Collectors.averagingDouble(Employee::getSalary) \/\/ \u6309\u90e8\u95e8\u8ba1\u7b97\u5e73\u5747\u85aa\u8d44:ml-citation{ref="10" data="citationList"}\n));<\/code><\/pre>\n\u4e09\u3001\u6027\u80fd\u9677\u9631\u4e0e\u89e3\u51b3\u65b9\u6848
\u200cStream\u94fe\u5f0f\u8c03\u7528\u5f00\u9500\u200c<\/p>\n
\u5408\u5e76\u540c\u7c7b\u64cd\u4f5c\uff1afilter().map()\u4f18\u4e8emap().filter()
\u907f\u514d\u91cd\u590d\u521b\u5efaStream\uff1a\u5bf9\u540c\u4e00\u96c6\u5408\u591a\u6b21\u8c03\u7528stream()\u4f1a\u751f\u6210\u65b0\u5bf9\u8c61
\u200c\u5e76\u884c\u6d41\u6ce8\u610f\u4e8b\u9879\u200c<\/p>\n
\u6570\u636e\u91cf\u5c0f\u4e8e1\u4e07\u65f6\u4e32\u884c\u6d41\u66f4\u5feb\uff08\u7ebf\u7a0b\u5207\u6362\u5f00\u9500\uff09
\u786e\u4fdd\u72b6\u6001\u65e0\u5173\uff1aforEachOrdered\u4fdd\u8bc1\u5e76\u884c\u6d41\u987a\u5e8f\u6027
\u56db\u3001\u51fd\u6570\u5f0f\u8bbe\u8ba1\u6a21\u5f0f
\u200c\u7b56\u7565\u6a21\u5f0fLambda\u5316\u200c<\/p>\n
java
Copy Code
\/\/ \u4f20\u7edf\u63a5\u53e3\u5b9e\u73b0
interface ValidationStrategy {<\/p>\n
boolean execute(String s);<\/code><\/pre>\n}
\/\/ Lambda\u5b9e\u73b0
ValidationStrategy numberCheck = s -> s.matches(“\/d+”); \/\/ \u6570\u5b57\u6821\u9a8c\u7b56\u7565:ml-citation{ref=”7,10″ data=”citationList”}
\u200c\u88c5\u9970\u5668\u6a21\u5f0f\u7ec4\u5408\u200c<\/p>\n
java
Copy Code
Function<String, String> addHeader = s -> “Header: ” + s;
Function<String, String> addFooter = s -> s + ” Footer”;
\/\/ \u7ec4\u5408\u88c5\u9970\u5668
Function<String, String> pipeline = addHeader.andThen(addFooter);:ml-citation{ref=”10″ data=”citationList”}
\u4e94\u3001\u6700\u65b0\u6280\u672f\u52a8\u6001\uff08JDK24\uff09
\u200cStream\u589e\u5f3a\u200c<\/p>\n
gather()\u64cd\u4f5c\u7b26\u652f\u6301\u81ea\u5b9a\u4e49\u4e2d\u95f4\u64cd\u4f5c
\u65b0\u589emapMulti\u66ff\u4ee3flatMap\u5904\u7406\u5d4c\u5957\u96c6\u5408
\u200c\u6a21\u5f0f\u5339\u914d\u6269\u5c55\u200c<\/p>\n
java
Copy Code
Object obj = “Hello”;
String result = switch(obj) {<\/p>\n
case String s when s.length()>5 -> "Long string"; \/\/ \u6a21\u5f0f\u5339\u914d+\u6761\u4ef6\u5224\u65ad:ml-citation{ref="9" data="citationList"}\ndefault -> "Other";<\/code><\/pre>\n};
\u200c\u6700\u4f73\u5b9e\u8df5\u200c\uff1a\u5728\u91d1\u878d\u4ea4\u6613\u7cfb\u7edf\u4e2d\uff0cLambda+Stream\u53ef\u4f7f\u6838\u5fc3\u903b\u8f91\u4ee3\u7801\u91cf\u51cf\u5c1140%\uff0c\u540c\u65f6\u63d0\u5347\u53ef\u7ef4\u62a4\u6027\u3002\u63a8\u8350\u4f7f\u7528@FunctionalInterface\u6ce8\u89e3\u660e\u786e\u63a5\u53e3\u8bbe\u8ba1\u610f\u56fe\u3002<\/p>\n