Java创建Stream方式小结

小咪咪 2023-01-17 11:00 118阅读 0赞

## Stream.of 可变参数 ##

Stream<String> stream = Stream.of("AA", "BB", "CC");
    System.out.println(stream.collect(joining()));

## Stream.of 数组 ##

String[] values = new String[]{ "AA", "BB", "CC"};
    Stream<String> stream = Stream.of(values);
    System.out.println(stream.collect(joining()));

## Arrays.stream ##

String[] values = new String[]{ "AA", "BB", "CC"};
    Stream<String> stream = Arrays.stream(values);
    System.out.println(stream.collect(joining()));

## List ##

List<String> list = List.of("AA", "BB", "CC");
    Stream<String> stream = list.stream();
    System.out.println(stream.collect(joining()));

## Set ##

Set<String> set = Set.of("AA", "BB", "CC");
    Stream<String> stream = set.stream();
    System.out.println(stream.collect(joining()));

## Map ##

Map<String, String> map = Map.of("1", "AA",
           "2", "BB",
            "3", "CC");
    Stream<String> stream = map.values().stream();
    System.out.println(stream.collect(joining()));

## Stream.iterate ##

Stream<Integer> stream = Stream.iterate(3, item -> item + 5);
    stream.forEach(System.out::println); //死循环

## Pattern ##

String value = "AA BB CC";
    Stream<String> stream = Pattern.compile("\\W").splitAsStream(value);
    System.out.println(stream.collect(joining()));

## Files.lines ##

try \{  
Stream stream9 = Files.lines(Paths.get(“d:/data.txt”));  
System.out.println(“stream9:” + stream9.collect(joining()));  
\} catch (IOException e) \{  
e.printStackTrace();  
\}  
data.txt文件内容如下：

A  
B  
C  
程序输出：

stream9:ABC

## Stream.generate ##

Stream stream10 = Stream.generate(() -> “A”).limit(3);  
System.out.println(“stream10:” + stream10.collect(joining()));  
程序输出：

stream10:AAA

好了，这是栈长整理的 10 种创建 Stream 的方式，是不是很骚？如果你还知道其他的骚操作，可以留言告诉大家，让大家记住你的头像和ID。