29 lines
751 B
Java
29 lines
751 B
Java
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// streams/Signal.java
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import java.util.*;
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import java.util.stream.*;
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import java.util.function.*;
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public class Signal {
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private final String msg;
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public Signal(String msg) { this.msg = msg; }
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public String getMsg() { return msg; }
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@Override
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public String toString() {
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return "Signal(" + msg + ")";
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}
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static class Generator implements Supplier<Signal> {
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Random rand = new Random(47);
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public Signal get() {
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switch(rand.nextInt(4)) {
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case 1: return new Signal("dot");
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case 2: return new Signal("dash");
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default: return null;
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}
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}
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}
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public static Stream<Optional<Signal>> stream() {
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return Stream.generate(new Generator())
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.map(signal -> Optional.ofNullable(signal));
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}
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}
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