final

问题 I need to add a progress listener to each element of the horizontal list view, how can I do that? For each item I upload a file. I wanna to do something like that but holder is not final, so I have an error. public class UploadsViewAdapter extends BaseAdapter { private Context mContext; private int mLayoutResourceId; List<Upload> listFileToUpload; public UploadsViewAdapter(Context context, int layoutResourceId, List<Upload> data) { this.mLayoutResourceId = layoutResourceId; this.mContext =

问题 Every time I create a TextView and set a text to it, the AS-Editor would throw an error: "Header expected - Manifest file doesn't end with a final newline" The code: <TextView android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="@string/hello_world" /> AndroidManifest.xml: <?xml version="1.0" encoding="utf-8"?> <manifest xmlns:android="http://schemas.android.com/apk/res/android" package="eu.myurl.myproject" android:versionCode="1" android:versionName="1.0" >

问题 I have a very simple question and just asking to know more about final method arguments. final variables can be initialized just once in its life. In JAVA method arguments are accepted as pass by value and reference is also passed as a value. Now my question is : How method doesn't know that passed object is final and already initialized? Here is sample code: public static void xyz(Abc obj) { System.out.println("hash code in xyz method :"+obj.hashCode()); obj = new Abc(); // here there is no

问题 Let's say I have the following base class: class Base { public: virtual void f() {}; }; If I want to write a class that will override the f() and will not allow to override it to it's derived classes can write it using following approaches: Approach 1: class Derived : public Base { public: virtual void f() override final {}; }; Approach 2: class Derived : public Base { public: void f() final {}; }; Approach 1 is a fully detailed when Approach 2 more compact and final still says that f() is

问题 I have the following class called A , with the method getValue() : public class A { public final int getValue() { return 3; } } The method getValue() always returns 3 , then i have another class called B , i need to implement something to access to the method getValue() in the class A , but i need to return 4 instead 3 . Class B : public class B { public static A getValueA() { return new A(); } } The main class ATest : import org.junit.Test; import static org.junit.Assert.assertEquals; import

问题 This question already has answers here : How to call a specific parent constructor from anonymous inner class? (3 answers) Closed 3 years ago . In Java, we can initialize a final field in constructors both in the base class and its subclasses, and also in an inline initializer block in the base class. However, it seems that we can not initialize final fields in an inline initializer block in a subclass. This behavior mainly affects anonymous classes from which super constructors can not be

问题 It's difficult to tell what is being asked here. This question is ambiguous, vague, incomplete, overly broad, or rhetorical and cannot be reasonably answered in its current form. For help clarifying this question so that it can be reopened, visit the help center. Closed 7 years ago . struct B { virtual void foo () { cout << "B::foo()\n"; } }; struct D : B { void foo () //final { cout << "D::foo()\n"; } }; int main () { B *pB = new B; D *pD = static_cast<D*>(pB); pB->foo(); pD->foo(); }

问题 I have a superclass and two subclasses that extend it. I'd like to initialize a variable called radius which can be set freely in subclass A, but is always the same for subclass B. I could initialize the variable every time I create an object B, but I was wondering if it's possible to make the variable final and static in subclass B, while still being able to implement a getter in my superclass. I might implement more subclasses which have a radius that's either final or variable. If not I'm

问题 public class Test { public static void main(String args[]){ Test t = new Test(); t.inner(); } public final void print() { System.out.print("main"); } public void inner() { class TestInner { void print(){ System.out.print("sub"); } } TestInner inner =new TestInner(); inner.print(); print(); } } Out put : submain Question : the method print() in class Test is final and is accessible to local class , but still local class is a able to define print() method again how? If we declare private final

问题 What does it mean to say that immutable objects can be published even without resorting to safe publication idioms? I have read Java Concurrency in Practice ( Chapter 3 , Sharing Objects ) but still not able to comprehend the statement : Immutable objects can be published through any mechanism. V/S Effectively immutable objects should be safely published. Edit: I have been through a similar question on SO and the answers but still unable to understand how immutable objects can be published