75 lines
2.5 KiB
Java
75 lines
2.5 KiB
Java
import java.io.IOException;
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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.*;
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import java.util.regex.Pattern;
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import java.util.stream.IntStream;
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import java.util.stream.Stream;
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class ExampleStreamCreation {
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public static void main(String[] args) {
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//Stream from values
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Stream stream = Stream.of(1);
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Stream<Character> charStream = Stream.of('a', 'b', 'c');
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Stream<String> strStream = Stream.of("Hello", "World");
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//Stream from a string
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IntStream intStream = "Hello World !!".chars();
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IntStream intStream1 = "Hello World !!".codePoints();
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//stream from pattern
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Pattern p = Pattern.compile(",");
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StringBuilder stringBuilder = new StringBuilder("1,2,3,4,5");
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Stream<String> patternStream = p.splitAsStream(stringBuilder);
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//stream from array
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Stream<Integer> intStream2 = Stream.of(new Integer[]{1, 2, 3, 4, 5});
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IntStream intStream3 = Arrays.stream(new int[]{1, 2, 3, 4});
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int[] mainArray = new int[]{1, 2, 3, 4, 5, 6, 7};
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IntStream s = Arrays.stream(mainArray, 2, 5);
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//stream from collection
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List<String> wordList = new ArrayList<>();
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wordList.add("Hello");
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wordList.add("World");
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Stream wordStream = wordList.stream();
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Stream parallelWordStream = wordList.parallelStream();
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//from a set
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Set set = new HashSet();
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set.add("First element");
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set.add("Second element");
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set.add("Third element");
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Stream setStream = set.stream();
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//empty stream
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Stream emptyStream = Stream.empty();
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Stream emptyStream1 = Stream.of();
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//from generate
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Stream.generate(new Random()::nextInt).limit(6).forEach(System.out::println);
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//from iterate
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Stream.iterate(3, n -> n + 1).limit(6).forEach(System.out::println);
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//from file
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try {
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Stream<String> fileStream = Files.lines(Paths.get("C:\\sample.txt"));
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fileStream.forEach(System.out::println);
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} catch (IOException e) {
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e.printStackTrace();
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}
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try {
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Optional<String> lineWithStreamWord = Files.lines(Paths.get("C:\\sample.txt")).filter(s1 -> s1.contains("stream")).findFirst();
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if (lineWithStreamWord.isPresent()) {
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System.out.println(lineWithStreamWord.get());
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}
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} catch (IOException e) {
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e.printStackTrace();
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}
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}
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} |