28 lines
768 B
Java
28 lines
768 B
Java
// enumerations/OddScoping.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} Since JDK 16
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public class OddScoping {
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static void f(Object o) {
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if(!(o instanceof String s)) {
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System.out.println("Not a String");
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throw new RuntimeException();
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}
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// s is in scope here!
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System.out.println(s.toUpperCase()); // [1]
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}
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public static void main(String[] args) {
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f("Curiouser and Curiouser");
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f(null);
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}
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}
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/* Output:
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CURIOUSER AND CURIOUSER
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Not a String
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Exception in thread "main" java.lang.RuntimeException
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at OddScoping.f(OddScoping.java:8)
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at OddScoping.main(OddScoping.java:15)
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*/
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