38 lines
858 B
Java
38 lines
858 B
Java
// streams/StreamOfOptionals.java
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// (c)2016 MindView LLC: see Copyright.txt
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// We make no guarantees that this code is fit for any purpose.
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// Visit http://mindviewinc.com/Books/OnJava/ for more book information.
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import java.util.*;
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import java.util.stream.*;
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public class StreamOfOptionals {
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public static void main(String[] args) {
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Signal.stream()
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.limit(10)
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.forEach(System.out::println);
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System.out.println(" ---");
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Signal.stream()
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.limit(10)
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.filter(Optional::isPresent)
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.map(Optional::get)
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.forEach(System.out::println);
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}
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}
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/* Output:
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Optional[Signal(dash)]
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Optional[Signal(dot)]
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Optional[Signal(dash)]
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Optional.empty
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Optional.empty
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Optional[Signal(dash)]
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Optional.empty
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Optional[Signal(dot)]
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Optional[Signal(dash)]
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Optional[Signal(dash)]
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---
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Signal(dot)
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Signal(dot)
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Signal(dash)
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Signal(dash)
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*/
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