47 lines
1.4 KiB
Java
47 lines
1.4 KiB
Java
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// enumerations/People.java
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// (c)2021 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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// {NewFeature} Preview in JDK 17
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// Compile with javac flags:
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// --enable-preview --source 17
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// Run with java flag: --enable-preview
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import java.util.*;
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record Person(String name, int age) {}
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public class People {
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static String categorize(Person person) {
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return switch(person) {
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case Person p && p.age() > 40 // [1]
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-> p + " is middle aged";
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case Person p &&
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(p.name().contains("D") || p.age() == 14)
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-> p + " D or 14";
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case Person p && !(p.age() >= 100) // [2]
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-> p + " is not a centenarian";
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case Person p -> p + " Everyone else";
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};
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}
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public static void main(String[] args) {
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List.of(
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new Person("Dorothy", 15),
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new Person("John Bigboote", 42),
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new Person("Morty", 14),
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new Person("Morty Jr.", 1),
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new Person("Jose", 39),
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new Person("Kane", 118)
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).forEach(
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p -> System.out.println(categorize(p))
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);
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}
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}
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/* Output:
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Person[name=Dorothy, age=15] D or 14
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Person[name=John Bigboote, age=42] is middle aged
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Person[name=Morty, age=14] D or 14
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Person[name=Morty Jr., age=1] is not a centenarian
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Person[name=Jose, age=39] is not a centenarian
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Person[name=Kane, age=118] is middle aged
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*/
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