32 lines
900 B
Java
32 lines
900 B
Java
// streams/OptionalsFromEmptyStreams.java
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// (c)2020 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://OnJava8.com for more book information.
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import java.util.*;
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import java.util.stream.*;
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class OptionalsFromEmptyStreams {
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public static void main(String[] args) {
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System.out.println(Stream.<String>empty()
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.findFirst());
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System.out.println(Stream.<String>empty()
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.findAny());
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System.out.println(Stream.<String>empty()
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.max(String.CASE_INSENSITIVE_ORDER));
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System.out.println(Stream.<String>empty()
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.min(String.CASE_INSENSITIVE_ORDER));
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System.out.println(Stream.<String>empty()
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.reduce((s1, s2) -> s1 + s2));
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System.out.println(IntStream.empty()
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.average());
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}
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}
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/* Output:
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Optional.empty
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Optional.empty
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Optional.empty
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Optional.empty
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Optional.empty
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OptionalDouble.empty
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*/
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