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globulon (18) [Avatar] Offline
Chap 4 classic constructor with a twist => default method as static ?

I was learning from chapter 4 when I read the compiler generates static method for obtaining the default value.
I ran with a test:

final class WithDefaultArgument {

def doSomething(withObject: String= "default"): Unit = {

def run() {


and javap produced:

public final class WithDefaultArgument implements scala.ScalaObject {
public void doSomething(java.lang.String);
0: getstatic #11 // Field scala/Predef$.MODULE$:Lscala/Predef$;
3: aload_1
4: invokevirtual #16 // Method scala/Predef$.printlnsmilieLjava/lang/ObjectsmilieV
7: return

public java.lang.String doSomething$default$1();
0: ldc #25 // String default
2: areturn

public void run();
0: aload_0
1: aload_0
2: invokevirtual #31 // Method doSomething$default$1smilie)Ljava/lang/String;
5: invokevirtual #33 // Method doSomethingsmilieLjava/lang/StringsmilieV
8: return

public WithDefaultArgument();
0: aload_0
1: invokespecial #38 // Method java/lang/Object."<init>"smilie)V
4: return


public java.lang.String doSomething$default$1()

seems not to be static. Am I missing something ?
joshua.suereth (60) [Avatar] Offline
Re: Chap 4 classic constructor with a twist =&gt; default method as static ?

I should clarify those examples a bit. Default values, in the case of 'modules' or package-level objects, are static. However, for classes they are instance methods so that they can be polymorphic. I'll go update that description to make sure it's accurate.