factory

问题 How do I make sure that a certain class is only instantiated by a factory and not by calling new directly? EDIT: I need the factory to be a separate class (for dependency injection purposes) so I can't make it a static method of the class to be instantiated, and so I can't make new private. 回答1: If, for some reason, you need the factory and the constructed class to be in separate assemblies (which means simply using internal won't work), and you can ensure that your factory gets a chance to

问题 In Java 9 we have convenience factory methods to create and instantiate immutable List, Set and Map. However, it is unclear about the specific type of the returned object. For ex: List list = List.of("item1", "item2", "item3"); In this case which type of list is actually returned? Is it an ArrayList or a LinkedList or some other type of List? The API documentation just mentions this line, without explicitly mentioning that its a LinkedList: The order of elements in the list is the same as the

问题 What is this factory all about and what are the advantages of using factory patterns? Does it give a plugable architecture? Why it is called "Factory"? 回答1: It is factory since it is actually "Manufacturing" (Create) an object. There's actually two kind of factory pattern defined by GoF: Factory Method Abstract Factory Basically both of them tries to decouple the calling client from knowing the actual concrete implementation of the class/interface. 回答2: You can find all you need by reading

问题 Do I have to move my getTemplates function out of the return or what ? Example : I dont know what to replace "XXXXXXX" with (I have tried "this/self/templateFactory" etc... ) : .factory('templateFactory', [ '$http', function($http) { var templates = []; return { getTemplates : function () { $http .get('../api/index.php/path/templates.json') .success ( function (data) { templates = data; }); return templates; }, delete : function (id) { $http.delete('../api/index.php/path/templates/' + id + '

问题 I am trying to include a library of functions, held in a factory, into a controller. Similar to questions like this: Creating common controller functions My main controller looks like this: recipeApp.controller('recipeController', function ($scope, groceryInterface, ...){ $scope.groceryList = []; // ...etc... /* trying to retrieve the functions here */ $scope.groceryFunc = groceryInterface; // would call ng-click="groceryFunc.addToList()" in main view /* Also tried this: $scope.addToList =

问题 Is there a way to map a factory method in Hibernate (as opposed to having Hibernate call a default constructor and reflectively set properties or fields)? And if it can't be mapped, does Hibernate provide a hook for custom object creation on a class by class basis? Thanks! 回答1: This is doable using either: a custom EntityPersister implementation (that you can register for a particular entity during Hibernate initialization using a custom Configuration) ~or~ a custom Interceptor implementing

问题 In my project I have some functions like std::tuple<VAO, Mesh, ShaderProgram> LoadWavefront(std::string filename); That I can use like this: VAO teapotVAO; Mesh teapotMesh; ShaderProgram teapotShader; std::tie(teapotVAO, teapotMesh, teapotShader) = LoadWavefront("assets/teapot.obj"); The problem is, this requires each of those classes to have a default constructor that creates them in an invalid state, which is error prone. How do I get around that without having to std::get<> each item? Is

问题 I'm looking for a better way to call functions based on a variable in Python vs using if/else statements like below. Each status code has a corresponding function if status == 'CONNECT': return connect(*args, **kwargs) elif status == 'RAWFEED': return rawfeed(*args, **kwargs) elif status == 'RAWCONFIG': return rawconfig(*args, **kwargs) elif status == 'TESTFEED': return testfeed(*args, **kwargs) ... I assume this will require some sort of factory function but unsure as to the syntax 回答1: The

问题 I'm looking for a better way to call functions based on a variable in Python vs using if/else statements like below. Each status code has a corresponding function if status == 'CONNECT': return connect(*args, **kwargs) elif status == 'RAWFEED': return rawfeed(*args, **kwargs) elif status == 'RAWCONFIG': return rawconfig(*args, **kwargs) elif status == 'TESTFEED': return testfeed(*args, **kwargs) ... I assume this will require some sort of factory function but unsure as to the syntax 回答1: The

问题 After ~10 months of procedural PHP, I'm now trying to wrap my head around basic OOP principles and design patterns. This is a hobby, and I haven't nearly as much time as I'd like to pursue it, so please forgive the rather low level of this question. My site (currently 100% procedural) is at heart a library. Visitors send the Library script 2 datapoints - an item type and item code . Library.php uses the item type to select an include, and the include grabs the code to hit the database and