protected

问题 I have the following code: class Base{ protected val alpha ="Alpha"; protected def sayHello = "Hello"; } class Derived extends Base{ val base = new Base; def hello = println(this.alpha +" "+this.sayHello) ; // def hello = println(base.alpha +" "+base.sayHello) ; // don't compile } object MyObj extends App{ val x=new Derived; x.hello; } In class Base , if I label protected with this , the code works as expected; if I don't label it with this , everything works as expected too. Are protected

问题 I am trying on a project to use private values in my internal functions. In past I used only public ones, but I noticed that obfuscation is working much better when using as much as possible private parameters. My question is regarding Parent/Child classes. In my main class I define all the parameters as following : public class MyFatherClass { private long id = -1; public long ID { get { return this.id; } set { this.id = value; } } ... } So in all internal functions I access to my private

问题 Here's the documentation for the protected method: /** Converts jmusic score data into a MIDI Sequence */ protected javax.sound.midi.Sequence scoreToSeq(Score score) And I made this little class to extend the class that scoreToSeq method comes from: public class MidiSequence extends MidiSynth{ public Sequence getSequence(Score score){ MidiSynth synth = new MidiSynth(); Sequence sequence = null; try { // Here I get the error saying that the method has // protected access in MidiSynth sequence

问题 I've a site and I would create a simply "Members only" page. I would add a protection to a page content so only editors and administrators can access. This page should be visible to all users, but when a guest click on it, the page content is protected by username/password. When user fill these fields, the page automatically redirect to protect content. Is there a plugin, or method, that I can consider? 回答1: There probely is some plugin for this kind of stuff, i mostly build my own themes,

问题 I have a base class, say BassClass , with some fields, which I made them protected, and some pure virtual functions. Then the derived class, say DerivedClass , like class DerivedClass : public BassClass . Shouldn't DerivedClass inherit the protected fields from BassClass? When I tried to compile the DerivedClass, the compiler complains that DerivedClass does NOT have any of those fields, what is wrong here? thanks 回答1: If BassClass (sic) and DerivedClass are templates, and the BassClass

问题 I have a base class, say BassClass , with some fields, which I made them protected, and some pure virtual functions. Then the derived class, say DerivedClass , like class DerivedClass : public BassClass . Shouldn't DerivedClass inherit the protected fields from BassClass? When I tried to compile the DerivedClass, the compiler complains that DerivedClass does NOT have any of those fields, what is wrong here? thanks 回答1: If BassClass (sic) and DerivedClass are templates, and the BassClass

问题 I've successfully programmed a singly linked list by the following program: The header file is: #ifndef SLL_H_ #define SLL_H_ #include <iostream> class node { protected: public: int key; node *next; node(); ~node(); }; class SLL : public node{ private: node *Head = NULL; int SLL_SIZE = 0; public: //Constructor SLL(); //SLL(int n); //Destructor ~SLL(); //Modifiers void Push_Front(int a); void Push_Back(SLL A,int b); void Traverse(); //Access function int SLL_size(); int Get(node* p); /

问题 I've been racking my brain trying to think of the best way to access a protected member function from some test code in C++, here's my problem: //in Foo.h Class Foo { protected: void DoSomething(Data data); } //in Blah.h Class Blah { public: Foo foo; Data data; }; //in test code... Blah blah; blah.foo.DoSomething(blah.data); // Here's my problem! Some possible solutions so far: Make the test code class a friend of Foo, but this pollutes Foo with test code Make DoSomething a public function I

问题 My question relates to Java, but it also can be applied to C#. I was wondering why everybody recommends making the instance variables private as opposed to making them protected . Let's just think about it. Private variables are not seen by the subclass, so if I need to access or change the variables of the superclass in my subclass I am forced to use some accessor and mutators method like getMyPrivateVariable or setMyPrivateVariable . But when you extend some class and inherit its members,

问题 Here is a sample of code that annoys me: class Base { protected: virtual void foo() = 0; }; class Derived : public Base { private: Base *b; /* Initialized by constructor, not shown here Intended to store a pointer on an instance of any derived class of Base */ protected: virtual void foo() { /* Some implementation */ }; virtual void foo2() { this->b->foo(); /* Compilator sets an error: 'virtual void Base::foo() is protected' */ } }; How do you access to the protected overrided function?