37 lines
922 B
Java
37 lines
922 B
Java
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// housekeeping/TypeInference.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 11
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class Plumbus {}
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public class TypeInference {
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void method() {
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// Explicit type:
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String hello1 = "Hello";
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// Type inference:
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var hello = "Hello!";
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// Works for user-defined types:
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Plumbus pb1 = new Plumbus();
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var pb2 = new Plumbus();
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}
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// Also works for static methods:
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static void staticMethod() {
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var hello = "Hello!";
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var pb2 = new Plumbus();
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}
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}
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class NoInference {
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String field1 = "Field initialization";
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// var field2 = "Can't do this";
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// void method() {
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// var noInitializer; // No inference data
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// var aNull = null; // No inference data
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// }
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// var inferReturnType() {
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// return "Can't infer return type";
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// }
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}
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