inner-classes

问题 This question already has answers here : java compiled classes contain dollar signs (4 answers) Closed 6 years ago . When i compile my java Enum Day, it generates his Day.class file and 8 Day$#.class Files, so i want to know why the compiler generates 8 $#.class instead of 7, because i have 7 enum constants, but 8 override annotations, i have understood that the Dollar.class files are generated for every inner class or by enum constants, but what about the eight .class file what it is

问题 I want to know if there are any constructors involved with inner classes. for example consider the code snippet given below class MyOuter { private int x= 10; class MyInner { void dostuff(){ System.out.println("The value of x is "+x); } } } In another java file i create instances for both MyOuter and MyInner classes as shown below Class Program { public static void main(String [] args) { MyOuter mo = new MyOuter(); MyOuter.MyInner mi = mo.new MyInner(); mi.dostuff(); } } The above code

问题 I'm just beginning to experiment with Android Development with SimpleXML and thought it was going quite well until I hit a snag. The code below produces an exception of W/System.err(665): org.simpleframework.xml.core.ConstructorException: Can not construct inner class I've looked through the questions on inner classes and think I understand why you would use them (not that mine was necessarily intentional) but despite moving my code round to try and avoid usage I'm still a little stuck and

问题 I can't seem to get the outer class members from an inner class reference: class Outer(st: Int) { val valOut = st def f = 4 class Inner { val x = 5 } } object myObj { val myOut = new Outer(8) val myIn = new myOut.Inner val myVal: Int = myIn.valOut//value f is not a member of ... myOut.Inner val x = myIn.f//value valOut is not a member of ... myOut.Inner } I've tried this inside packages and in the eclipse worksheet neither works. I'm using Scala 2.10.0RC1 in eclipse 3.7.2 with Scala plug-in 2

问题 I have c class definition and some inner class definitions for that class: class DoXJob(): def __init__(self, param1, param2): <choose an inner class to use> def DoIt(self): pass def Finalize(self): <do finalization> class DoXInSomeWay(): def __init__(self): .... .... def DoIt(self): ... class DoXInSomeOtherWay(): def __init__(self): .... .... def DoIt(self): ... Logic is simple, i have some inner class definitions to handle a job, and i call DoXJob with some parameters, it then decides which

问题 I am having an issue combining generics, implements , and inner classes. I am creating a LinkedBinaryHeap class which contains an inner class. This inner class is the generic HeapNode which extends the generic Node class I created; it just adds a variable and methods for a key/priority. In LinkedBinaryHeap I create a generic LinkedList to store HeapNode s. I am assuming the generic data being stored extends Comparable class. Here is a layout of what stores what: BinaryHeap->LinkedList(Nodes)-

问题 C++ How can I put the definition of an inner (nested) class outside its outer (enclosing) class's definition, where the outer class has at least one instance of the inner class as a data member? I searched but the most relevant SO answer I found, Nested Class Definition in source file, does not have an example where the outer class has an inner object as a data member. I followed that answer, as far as declaring but not defining the inner class inside the outer class's definition is concerned

问题 I have an Activity with one button to quit the Activity . Through the layout.xml I have to set the OnClick event to cmd_exit and a call to 'this.finish()' works fine public void cmd_exit(View editLayout){ this.finish(); } , but when I add a OnClickListener instead cmd_exit = (Button) this.findViewById(R.id.cmd_ExitApp); cmd_exit.setOnClickListener(new View.OnClickListener() { @Override public void onClick(View view) { finish(); } }); this.finish() gives error. It has to be only finish() . I

问题 Why can't a java nested Interface be non-static ? And why can't an inner class contain static non final members ? I came across the questions while going through Gosling and haven't been able to figure out the answer yet. 回答1: If an nested class is non-static (i.e. an inner class), this means that each instance of it is bound to an instance of the outer class. As an interface has no instances of its own, it seems to not be useful for the implementing classes to be bound to an outer object, so

问题 This is quite a complicated error, so please bear with me. I am seeing a weird error when trying to compile some Java code. The compiler fails to recognise a static inner class . Let us say that I am working on a class MyClass . The static inner class which I need to use has an FQN of x.y.z.Parent.DesiredClass . This inner class is explicitly imported using its FQN. The parent is also imported using its FQN. Now there exists another package with (another, different FQN) which has a class