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    <p>I don't fully agree with @edutesoy answer. </p> <p><a href="http://en.wikipedia.org/wiki/First-class_object" rel="nofollow noreferrer">First-class</a> means that an implicit constructs is reified as an explicit construct that can be passed around like any object. Classes in Java are not "first-class", they are mirrors where you can inspect some properties but are not the the object itself. </p> <p>That you can not change the structure of the class at run-time is fine, e.g. add fields, change method body or signature, and that under this perspective it's partly "read-only" is ok. </p> <p>But let's consider static fields. I guess everybody agrees that unless <code>final</code> static fields are mutable, just like instance fields. In Smalltalk, these are just fields defined on the class itself, rather than on instances of the class. Also, in Smalltalk, class-side methods are polymorphic just like any other method, and :</p> <pre><code>aClass field: aValue. </code></pre> <p>might resolve differently depending on the class that is passed. This is not possible in Java ; a static field or method must be referenced via its <em>type</em>. This also means that it does not <a href="https://stackoverflow.com/questions/2223386/why-doesnt-java-allow-overriding-of-static-methods/2223408#2223408">allow overriding static methods</a> (read the link for more details) as would be the case if they were truely first class. </p> <p>The fact that reflection is possible in Java doesn't make classes "first-class"--you can only pass a representation of the class around. And to come back to the original question: I don't know of any statically typed language with first-class classes (but my knowledge is limited, maybe one exists).</p> <p><strong>EDIT</strong></p> <p>Actually, now I remember it exists StrongTalk (<a href="http://www.strongtalk.org/" rel="nofollow noreferrer">http://www.strongtalk.org/</a>) which is Smalltalk with static typing. The typing issues are discussed in this paper: <a href="http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.95.6935&amp;rep=rep1&amp;type=pdf" rel="nofollow noreferrer">Strongtalk: Typechecking Smalltalk in a Production Environment</a></p>
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    1. POIs there any static language in which a class is an object?
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    1. COInteresting, I didn't know, but why a Java Class class instance is not a first-class object? I think that it meets the 5 requirements claimed in your wikipedia reference.
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    2. CO@edutesoy What is first-class is indeed a bit fuzzy notion. But 1) `String` itself is not an object, only `String.class` is 2) static method are not bound to a class object and hence not polymorphic 3) classes can be created only via classloaders (point #4 of the definition). That `String.class` is an object is clear, but the reflective treatment of classes as object is not as first-class as, say, in Smalltalk.
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