First contact with “var” in Java 10

I present to you the translation of the article First Contact With 'var' In Java 10 by Nicolai Parlog .



Java 10 will be released on March 20, 2018 , and all the features that should be in this release are already merged into the main development branch. One of the most interesting innovations of Java 10 is the inference of the type of a local variable ( JEP 286 ). This gives you the opportunity to shorten variable declarations using the new var keyword:
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URL codefx = new URL("http://codefx.org");

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foo = "Foo";

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var ints = {0, 1, 2};
var appendSpace = a -> a + " ";
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var numbers = List.of("a", "b", "c");
for (var nr : numbers)
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InternationalCustomerOrderProcessor<AnonymousCustomer, SimpleOrder<Book>> orderProcessor = createInternationalOrderProcessor(customer, order);

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No no = new No();
AmountIncrease<BigDecimal> more = new BigDecimalAmountIncrease();
HorizontalConnection<LinePosition, LinePosition> jumping =
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Variable variable = new Constant(5);
List<String> names = List.of("Max", "Maria");
 
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var no = new No();
var more = new BigDecimalAmountIncrease();
var jumping = new HorizontalLinePositionConnection();
var variable = new Constant(5);
var names = List.of("Max", "Maria");

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