autoboxing Questions

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Is there a way how to disable auto-boxing for Java 5 and 6 in IntelliJ IDEA, to not allow a developer to use this feature in the IDE?
Dacoity asked 4/4, 2013 at 18:27

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I have this singleton I'm trying to use, but getInstance can apparently return null: class Singleton { public static final String K_LEVEL = "level"; static Singleton instance = new Singleton(); ...
Lanellelanette asked 26/3, 2013 at 21:34

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I've searched for the use of @specialized in the source code of the standard library of Scala 2.8.1. It looks like only a handful of traits and classes use this annotation: Function0, Function1, Fu...

9

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I have been told to never use == for strings but for everything else because .equals would compare the values rather than the instances of the object. (Which I understand the difference of). Accor...
Riebling asked 11/11, 2011 at 14:22

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Is this autoboxing? Object ob = 8; Will the above code first wrap the int literal 8 in an Integer and then assign its reference to variable ob? Because the java language specification has nothin...
Dewy asked 28/2, 2013 at 15:17

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I would like to generate warnings for ALL autoboxing and unboxing. Has anyone found an effective way? Eclipse catches basic autoboxing errors: eg. Integer i = null; i++. But fails on anything com...
Funiculate asked 22/2, 2013 at 9:16

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Today I've been playing around with Eclipse Juno. Coming from Helios it is a great upgrade. Everything is working fine, except one new compile error. We are using the java.net framework 'Fuse' and...
Utley asked 4/7, 2012 at 6:18

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public class Test { public static void main(String[] args) { String s = null; String s1 = null; Integer i = null; Integer i1 = null; System.out.println(s+i); System.out.println(i+s); Syst...
Glottis asked 26/1, 2013 at 16:24

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Why groups j=k*l and m=n*o have different performance, while first 3 groups have the same ? int a = 42; int b = 42; int c = 42; Integer d = 42; int e = 42; int f = 42; int g = 42; Integer h = 42...
Triplicity asked 28/1, 2013 at 8:17

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Just trying to understand auto-boxing, which I do apart from one thing: Short s = 250; Long l = 250; The assignment to Long l fails. This, I expect, is because you cannot widen then box (i.e. it...
Anabiosis asked 20/1, 2013 at 14:43

2

I've been looking at autoboxing in Objective-C (here, for instance). Is there a new syntax for unboxing? For instance, I want to do this but shorter: NSArray *oneNumber = @[@1]; int one = ((NSNu...
Photoactinic asked 15/1, 2013 at 16:30

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This question is about "Why does autoboxing make some calls ambiguous in Java?" But reading through the answers, there are a number of references to casting and I'm not sure I completely understan...
Arnoldoarnon asked 1/2, 2009 at 21:53

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Possible Duplicate: Java: Long result = -1: cannot convert from int to long For example Integer foo = 4 and Long foo = 4L both compile, but Long foo = 4 doesn't. Is there a rationale ...
Rill asked 17/12, 2012 at 13:14

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The following program prints respectively 'false' and 'true': Number n = true ? new Long(1) : new Double(2.0); System.out.println(n instanceof Long); System.out.println(n instanceof Double); So ...
Forage asked 8/10, 2012 at 20:20

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I tripped across a really strange NullPointerException the other day caused by an unexpected type-cast in the ternary operator. Given this (useless exemplary) function: Integer getNumber() { retu...
Brick asked 6/10, 2012 at 21:21

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I am a java novice and so confused by the following example. Is it okay to think that "==" sign will compare the values between Integers and "autoboxed" Integers from int, and compare reference add...
Near asked 24/9, 2012 at 6:3

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When you concatenate a String with a primitive such as int, does it autobox the value first. ex. String string = "Four" + 4; How does it convert the value to a string in Java?
Softboiled asked 16/9, 2012 at 7:10

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I am getting the Findugs error "A boxed value is unboxed and then immediately reboxed". This is the Code: Employee emp = new Employee() Long lmt = 123L; emp.setLimit(Long.valueOf(lmt)); In th...
Capacity asked 22/8, 2012 at 5:18

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In Scala, { x: Option[Int] => x } .getClass .getMethod("apply", classOf[Option[_]]) .getGenericParameterTypes returns Array(scala.Option<java.lang.Object>). I'd initially been expec...
Schoenburg asked 23/6, 2012 at 6:30

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I program in Java, C and Python. The rule for automatic coercions among arithmetic types have been augmented to handle the richer set of types Source: "The C Programming Language"...
Lawsuit asked 18/6, 2012 at 15:34

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I'm learning Java on my own; and therefore the code below has no function other than for learning/testing. Essentially I'm trying to modify the elements of an Integer array (namely, halving them) ...
Ament asked 14/6, 2012 at 11:36

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For performance and safety I would like to implement a fixed-size vector which is both immutable and specialized (I need fast arithmetics). My first idea was to use the @specialized annotation (bec...
Roderica asked 21/4, 2012 at 9:28

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I have a trait and an implementation looking like: trait Foo[A] { def bar[B >: A: Ordering]: Foo[B] } class FooImpl[A]( val a: A, val values: List[Foo[A]] ) extends Foo[A] { def bar[B >: A...
Busman asked 17/4, 2012 at 15:58

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Possible Duplicate: Tricky ternary operator in Java - autoboxing We know that int roomCode = null; is not allowed by the compiler. Then why the Code 1 doesn't give a compiler error, ...
Turley asked 23/2, 2012 at 5:49

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I noticed today that auto-boxing can sometimes cause ambiguity in method overload resolution. The simplest example appears to be this: public class Test { static void f(Object a, boolean b) {} s...
Afterbrain asked 1/2, 2009 at 19:20

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