60 lines
1.8 KiB
Java
60 lines
1.8 KiB
Java
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package cn.bunny.stream;
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import java.io.IOException;
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import java.nio.charset.StandardCharsets;
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import java.nio.file.Files;
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import java.nio.file.Paths;
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import java.util.Arrays;
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import java.util.HashMap;
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import java.util.Map;
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import java.util.concurrent.ThreadLocalRandom;
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import java.util.stream.IntStream;
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import java.util.stream.Stream;
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public class StreamExample01 {
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public static void main(String[] args) throws IOException {
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Stream<Integer> build = Stream.<Integer>builder()
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.add(1)
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.add(12)
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.add(3)
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.add(34)
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.build();
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Stream<Integer> integerStream = Stream.of(1, 2, 34, 5);
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// 空Stream
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Stream<Object> objectStream = Stream.empty();
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// Stream.generate创建
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Stream.generate(() -> ThreadLocalRandom.current().nextInt(10))
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.limit(10)
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.forEach(System.out::println);
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// 不加限制会一直创建
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Stream.iterate(100, seed -> seed + 1)
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.limit(10)
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.forEach(System.out::println);
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// IntStream创建[1,10)
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IntStream.range(1, 10)
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.forEach(System.out::println);
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// 创建闭区间[1,10]
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IntStream.rangeClosed(1, 10)
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.forEach(System.out::println);
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// Arrays.asList创建
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Arrays.asList("a", "b", "c", "d", "e", "f")
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.forEach(System.out::println);
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// 创建Stream<Map.Entry<String, String>>
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Stream<Map.Entry<String, String>> stream = new HashMap<String, String>() {{
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put("a", "b");
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put("c", "d");
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}}.entrySet().stream();
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// Files中的Stream
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Stream<String> lines = Files.lines(Paths.get("xxx.md"), StandardCharsets.UTF_8);
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}
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}
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