encapsulation

Very recently I came across the Reflection API and to my surprise we can access and even alter the private variables.I tried the following code import java.lang.reflect.Field; public class SomeClass{ private String name = "John"; } public class Test{ public static void main(String args[]) throws Exception { SomeClass myClass = new SomeClass(); Field fs = myClass.getClass().getDeclaredField("name"); fs.setAccessible(true); System.out.println("Variable is " + fs.getName() + " and value is " + fs.get(myClass)); fs.set(myClass, "Sam"); System.out.println("Variable is " + fs.getName() + " and value

For practice, I'm implementing a queue data type in a module called "Queue". My data type is also called "Queue", as is its only value constructor: module Queue (Queue, enq, emptyQueue) where data Queue a = Queue { inbox :: [a], outbox :: [a] } deriving (Eq, Show) emptyQueue :: Queue a emptyQueue = Queue [] [] enq :: a -> Queue a -> Queue a enq x (Queue inb out) = Queue (x:inb) out -- other function definitions (irrelevant here)... As far as I understand, because I wrote Queue , not Queue(..) or Queue(Queue) in the export statement, I don't expect the value constructor of my data type to be

Good day! I am reading a Java book about encapsulation and it mentioned the getter and setter method. I've read that to hide the attributes, I must mark my instance variables as "PRIVATE" and make a "PUBLIC" method of getter and setter to access the data. So I tried making a similar but not the conventional code about it as follows: public class AddressBookEntry { private String name; private String address; private String telNo; private String email; public void getAllInfo() { name = JOptionPane.showInputDialog("Enter Name: "); address = JOptionPane.showInputDialog("Enter Address: "); telNo =

Related: Get enum from enum attribute I want the most maintainable way of binding an enumeration and it's associated localized string values to something. If I stick the enum and the class in the same file I feel somewhat safe but I have to assume there is a better way. I've also considered having the enum name be the same as the resource string name, but I'm afraid I can't always be here to enforce that. using CR = AcmeCorp.Properties.Resources; public enum SourceFilterOption { LastNumberOccurences, LastNumberWeeks, DateRange // if you add to this you must update FilterOptions.GetString }

For decently sized projects I've been told that when you have classes extending JPanels that the best practice is to use nested classes to implement the listeners. For example I could have a class FactoryScreen that extends JPanel, and have a nested class FactoryScreenBrain that implements all the necessary listeners. I've never been able to get a good explanation for specific benefits or disadvantages to encapsulating my classes in this fashion, and until now have always just had classes that both extend JPanel and implement listeners. Can someone provide me some guidance on this? Having

I would like to use the Eigen matrix library as the linear algebra engine in my program. Eigen uses expression templates to implement lazy evaluation and to simplify loops and calculations. For example: #include<Eigen/Core> int main() { int size = 40; // VectorXf is a vector of floats, with dynamic size. Eigen::VectorXf u(size), v(size), w(size), z(size); u = 2*v + w + 0.2*z; } Since Eigen uses expression templates, code like u = 2*v + w + 0.2*z; In the above mentioned sample reduces to a single loop of length 10 (not 40, the floats are put into regiser by chunks of 4) without creating a