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  • Ruby get inheriting class

    - by Brian D.
    I'm working on creating my first plugin for rails. I'm still pretty new to ruby and I was wondering if its possible to get the inheriting class? For example, I'm trying to create a plugin that will allow unit testing and functional testing when you are not using migrations. What I'm trying to do is initialize a class variable named controller to be initialized to the type of controller that is being tested. If I have a base class ControllerTest: class ControllerTest < Test::Unit::TestCase attr_accessor :controller def initialize super @controller = "call function that will find the inheriting classes name and create an instance of that controller type." end end So what I'm currently stuck on is getting the name of the inheriting class. Is this possible? And if not, does anyone know another way on how I could go about implementing this? Thanks in advance.

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  • Field Members vs Method Variables?

    - by Braveyard
    Recently I've been thinking about performance difference between class field members and method variables. What exactly I mean is in the example below : Lets say we have a DataContext object for Linq2SQL class DataLayer { ProductDataContext context = new ProductDataContext(); public IQueryable<Product> GetData() { return context.Where(t=>t.ProductId == 2); } } In the example above, context will be stored in heap and the GetData method variables will be removed from Stack after Method is executed. So lets examine the following example to make a distinction : class DataLayer { public IQueryable<Product> GetData() { ProductDataContext context = new ProductDataContext(); return context.Where(t=>t.ProductId == 2); } } (*1) So okay first thing we know is if we define ProductDataContext instance as a field, we can reach it everywhere in the class which means we don't have to create same object instance all the time. But lets say we are talking about Asp.NET and once the users press submit button the post data is sent to the server and the events are executed and the posted data stored in a database via the method above so it is probable that the same user can send different data after one another.If I know correctly after the page is executed, the finalizers come into play and clear things from memory (from heap) and that means we lose our instance variables from memory as well and after another post, DataContext should be created once again for the new page cycle. So it seems the only benefit of declaring it publicly to the whole class is the just number one text above. Or is there something other? Thanks in advance... (If I told something incorrect please fix me.. )

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  • How to keep an Hibernate's Session open until the page is rendered

    - by Neuquino
    I'm having the following problem: I'm using Oracle ADF for the view and controller of my app. With OpenSessionInViewFilter, I intercept the request and open an Hibernate's Session, and it is closed as soon as the bean's method finishes. What I need is to keep the Session opened until the page is rendered, because in my JSP y use the lazy attributes of the object i load from the DB. For example: When I enter index.jspx the IndexBean#main() is executed: public class IndexBean{ private DBObject myDBObject; public String main(){ this.myDBObject = this.myDAO.loadObjectFromDB(); return null; } } in index.jspx I have: ... <af:inputText value="#{myDBObject.lazyAttribute}" /> ... I'd like that the Hibernate's Session keeps open until the af:inputText is processed. Is this possible? How? Thanks in advance

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  • abstract class MouseAdapter vs. interface

    - by Stefano Borini
    I noted this (it's a java.awt.event class). public abstract class MouseAdapter implements MouseListener, MouseWheelListener, MouseMotionListener { .... } Then you are clearly forced to extend from this adapter public class MouseAdapterImpl extends MouseAdapter {} the class is abstract and implements no methods. Is this a strategy to combine different interfaces into a single "basically interface" ? I assume in java it's not possible to combine different interfaces into a single one without using this approach. In other words, it's not possible to do something like this in java public interface MouseAdapterIface extends MouseListener, MouseWheelListener, MouseMotionListener { } and then eventually public class MouseAdapterImpl implements MouseAdapterIface {} Is my understanding of the point correct ? what about C# ?

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  • C#: Abstract classes need to implement interfaces?

    - by bguiz
    My test code in C#: namespace DSnA { public abstract class Test : IComparable { } } Results in the following compiler error: error CS0535: 'DSnA.Test' does not implement interface member 'System.IComparable.CompareTo(object)' Since the class Test is an abstract class, why does the compiler require it to implement the interface? Shouldn't this requirement only be compulsory for concrete classes?

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  • Get class of caller's method (via inspect) in Python (alt: super() emulator)

    - by Slava Vishnyakov
    Is it possible to get reference to class B in this example? class A(object): pass class B(A): def test(self): test2() class C(B): pass import inspect def test2(): frame = inspect.currentframe().f_back cls = frame.[?something here?] # cls here should == B (class) c = C() c.test() Basically, C is child of B, B is child of A. Then we create c of type C. Then the call to c.test() actually calls B.test() (via inheritance), which calls to test2(). test2() can get the parent frame frame; code reference to method via frame.f_code; self via frame.f_locals['self']; but type(frame.f_locals['self']) is C (of course), but not B, where method is defined. Any way to get B?

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  • Ruby: Locate class definition at run time?

    - by Thor Thurn
    I'm having an odd probably with rails right now... a class is being defined somewhere, and I can't find it. Grepping for "class ClassName" hasn't managed to locate it, but it's definitely there when I load up the rails console. It's just a vanilla class inheriting from Object with nothing else defined... quite boring. So, what I'd like is a way to figure out where this class constant was originally defined from the rails console. Something to print out the value of '__ FILE __' when this class was declared, in other words. I feel like some type of metaprogramming should make this possible.

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  • In PHP, is it possible to create an instance of an class without calling class's constructor ?

    - by Rachel
    By any means, is it possible to create an instance of an php class without calling its constructor ? I have Class A and while creating an instance of it am passing file and in constructor of Class A am opening the file. Now in Class A, there is function which I need to call but am not required to pass file and so there is not need to use constructor functionality of opening file as am not passing file. So my question is, Is it possible by any means to create an instance of an PHP class without calling its constructor ?

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  • Image not loading onto JPanel?

    - by None None
    I have been trying to figure out how to add an image to a JPanel as a background, but still have complete control over the placing of JButtons, JLabels, and etc. This is one method I found, but it is crashing and not loading the image or buttons. Here is the code: import javax.swing.JFrame; import javax.swing.JPanel; import javax.swing.JButton; import java.awt.BorderLayout; import java.awt.FlowLayout; import java.awt.GridLayout; public class PanelDemo extends JFrame { private static final long serialVersionUID = 1L; private JButton btn1 = new JButton("EASY"); private JButton btn2 = new JButton("MEDIUM"); private JButton btn3 = new JButton("HARD"); private JButton btn4 = new JButton("High Score"); public PanelDemo() { super("Image Panel Demo"); JPanel panel = new ImagePanel( new FlowLayout(FlowLayout.CENTER, 50, 180)); JPanel panelbtn = new JPanel(new GridLayout(4, 1)); btn1.setBackground(new java.awt.Color(0, 0, 0)); btn1.setFont(new java.awt.Font("Showcard Gothic", 1, 24)); btn1.setForeground(new java.awt.Color(0, 255, 102)); btn2.setBackground(new java.awt.Color(0, 0, 0)); btn2.setFont(new java.awt.Font("Showcard Gothic", 1, 24)); btn2.setForeground(new java.awt.Color(0, 255, 102)); btn3.setBackground(new java.awt.Color(0, 0, 0)); btn3.setFont(new java.awt.Font("Showcard Gothic", 1, 24)); btn3.setForeground(new java.awt.Color(0, 255, 102)); btn4.setBackground(new java.awt.Color(0, 0, 0)); btn4.setFont(new java.awt.Font("Showcard Gothic", 1, 24)); btn4.setForeground(new java.awt.Color(0, 255, 102)); panel.add(panelbtn); panelbtn.add(btn1); panelbtn.add(btn2); panelbtn.add(btn3); panelbtn.add(btn4); add(panel, BorderLayout.CENTER); setSize(640, 480); setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); } public static void main(String... args) { new PanelDemo().setVisible(true); } } ImagePanel.java import java.awt.Graphics; import java.awt.Image; import java.awt.LayoutManager; import javax.swing.ImageIcon; import javax.swing.JPanel; public class ImagePanel extends JPanel { private static final long serialVersionUID = 1L; String imageFile = "/rsc/img/background.jpg"; public ImagePanel() { super(); } public ImagePanel(String image) { super(); this.imageFile = image; } public ImagePanel(LayoutManager layout) { super(layout); } public void paintComponent(Graphics g) { ImageIcon imageicon = new ImageIcon(getClass().getResource(imageFile)); Image image = imageicon.getImage(); super.paintComponent(g); if (image != null) g.drawImage(image, 0, 0, getWidth(), getHeight(), this); } } Error: Exception in thread "AWT-EventQueue-0" java.lang.NullPointerException at javax.swing.ImageIcon.<init>(Unknown Source) at ImagePanel.paintComponent(ImagePanel.java:27) at javax.swing.JComponent.paint(Unknown Source) at javax.swing.JComponent.paintChildren(Unknown Source) at javax.swing.JComponent.paint(Unknown Source) at javax.swing.JComponent.paintChildren(Unknown Source) at javax.swing.JComponent.paint(Unknown Source) at javax.swing.JLayeredPane.paint(Unknown Source) at javax.swing.JComponent.paintChildren(Unknown Source) at javax.swing.JComponent.paintToOffscreen(Unknown Source) at javax.swing.RepaintManager$PaintManager.paintDoubleBuffered(Unknown Source) at javax.swing.RepaintManager$PaintManager.paint(Unknown Source) at javax.swing.RepaintManager.paint(Unknown Source) at javax.swing.JComponent.paint(Unknown Source) at java.awt.GraphicsCallback$PaintCallback.run(Unknown Source) at sun.awt.SunGraphicsCallback.runOneComponent(Unknown Source) at sun.awt.SunGraphicsCallback.runComponents(Unknown Source) at java.awt.Container.paint(Unknown Source) at java.awt.Window.paint(Unknown Source) at javax.swing.RepaintManager$3.run(Unknown Source) at javax.swing.RepaintManager$3.run(Unknown Source) at java.security.AccessController.doPrivileged(Native Method) at java.security.ProtectionDomain$1.doIntersectionPrivilege(Unknown Source) at javax.swing.RepaintManager.paintDirtyRegions(Unknown Source) at javax.swing.RepaintManager.paintDirtyRegions(Unknown Source) at javax.swing.RepaintManager.prePaintDirtyRegions(Unknown Source) at javax.swing.RepaintManager.access$1000(Unknown Source) at javax.swing.RepaintManager$ProcessingRunnable.run(Unknown Source) at java.awt.event.InvocationEvent.dispatch(Unknown Source) at java.awt.EventQueue.dispatchEventImpl(Unknown Source) at java.awt.EventQueue.access$200(Unknown Source) at java.awt.EventQueue$3.run(Unknown Source) at java.awt.EventQueue$3.run(Unknown Source) at java.security.AccessController.doPrivileged(Native Method) at java.security.ProtectionDomain$1.doIntersectionPrivilege(Unknown Source) at java.awt.EventQueue.dispatchEvent(Unknown Source) at java.awt.EventDispatchThread.pumpOneEventForFilters(Unknown Source) at java.awt.EventDispatchThread.pumpEventsForFilter(Unknown Source) at java.awt.EventDispatchThread.pumpEventsForHierarchy(Unknown Source) at java.awt.EventDispatchThread.pumpEvents(Unknown Source) at java.awt.EventDispatchThread.pumpEvents(Unknown Source) at java.awt.EventDispatchThread.run(Unknown Source) Also, if anyone knows of a better way to put a background image on a JPanel, pease do tell. Thank you in advance.

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  • Check if CSS Class exists in StyleSheet using javascript/jQuery

    - by Akhil Sekharan
    Is there a way to check if there is a class named 'some-class-name' in css? For example, I have: <style type="text/css"> .box { position: absolute; left: 150%; } </style> My intention is to randomly assign a class to a div on certain event: var classList = []; //Need to populate this array $('#updateClass').on('click', function() { $('#resultDiv').attr('class',classList[Math.floor((Math.random()*classList.length)+1)]); }); Is it possible to check by JS/jQuery whether a class named 'box' exists in the stylesheet? Thanks.

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  • Class Not found exception in JApplet.

    - by Nitesh Panchal
    Hello, I created a simple Applet using JApplet and everything seems to work fine but as soon i create an object of my userdefined class named ChatUser in my applet, i get this error :- SEVERE: java.lang.ClassNotFoundException: applet.ChatUser at com.sun.enterprise.loader.ASURLClassLoader.findClassData(ASURLClassLoader.java:713) at com.sun.enterprise.loader.ASURLClassLoader.findClass(ASURLClassLoader.java:626) at java.lang.ClassLoader.loadClass(ClassLoader.java:307) at java.lang.ClassLoader.loadClass(ClassLoader.java:252) at java.lang.ClassLoader.loadClassInternal(ClassLoader.java:320) at java.lang.Class.forName0(Native Method) at java.lang.Class.forName(Class.java:247) at java.io.ObjectInputStream.resolveClass(ObjectInputStream.java:604) at java.io.ObjectInputStream.readNonProxyDesc(ObjectInputStream.java:1575) at java.io.ObjectInputStream.readClassDesc(ObjectInputStream.java:1496) at java.io.ObjectInputStream.readOrdinaryObject(ObjectInputStream.java:1732) at java.io.ObjectInputStream.readObject0(ObjectInputStream.java:1329) at java.io.ObjectInputStream.readObject(ObjectInputStream.java:351) at misc.ChatClient.run(ChatClient.java:43) Any idea what can be wrong? It only happens when i create an object of any user defined class. Do i need to set some security settings or something? Please help :(

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  • Ruby: Calling class method from instance

    - by Peter
    In Ruby, how do you call a class method from one of that class's instances? Say I have class Truck def self.default_make # Class method. "mac" end def initialize # Instance method. Truck.default_make # gets the default via the class's method. # But: I wish to avoid mentioning Truck. Seems I'm repeating myself. end end the line Truck.default_make retrieves the default. But is there a way of saying this without mentioning Truck? It seems like there should be.

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  • launch android activity from non-activity class

    - by Alberto Barrera
    im New on Android. I know theres a lot of similar Questions but anyone is helping. Im using a 3rd party app that just launch a class that extends their own class. So from that class i would like to launch an activity. public class SkyTest extends VtiUserExit { @Override public VtiUserExitResult execute() throws VtiExitException { // TODO Auto-generated method stub logInfo("TEST"); return null; } } How do i launch an activity named MainActivity from here. i tryed this: Context context = null; Intent intent = new Intent(context, MainActivity.class); context.startActivity(intent); but its not working, i know i cant use the null context, but how do i create a context o how it works? Thanks

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  • What are Class methods in Python for?

    - by Dave Webb
    I'm teaching myself Python and my most recent lesson was that Python is not Java, and so I've just spent a while turning all my Class methods into functions. I now realise that I don't need to use Class methods for what I would done with static methods in Java, but now I'm not sure when I would use them. All the advice I can find about Python Class methods is along the lines of newbies like me should steer clear of them, and the standard documentation is at its most opaque when discussing them. Does anyone have a good example of using a Class method in Python or at least can someone tell me when Class methods can be sensibly used?

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  • PHP: friend classes and ungreedy caller function/class

    - by avetis.kazarian
    Is there any way to get the caller function with something else than debug_backtrace()? I'm looking for a less greedy way to simulate scopes like friend or internal. Let's say I have a class A and a class B. Until now, I've been using debug_backtrace(), which is too greedy (IMHO). I thought of something like this: <?php class A { public function __construct(B $callerObj) {} } class B { public function someMethod() { $obj = new A($this); } } ?> It might be OK if you want to limit it to one specific class, but let's say I have 300 classes, and I want to limit it to 25 of them? One way could be using an interface to aggregate: public function __construct(CallerInterface $callerObj) But it's still an ugly code. Moreover, you can't use that trick with static classes. Have any better idea?

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  • Pass logger instance to class

    - by mridang
    Hi Guys, I'm using a open-source Python library in my project. This library logs a lot of information using the logging class. ...but I can't see the output or log it to file. I know that i would have to create a logger instance and add a file-handler or a console-handler to it but how can i pass this logger instance to the class? Here's the init snippet of the class that I'm going to be using. class Periscope: ''' Main Periscope class''' def __init__(self): self.config = ConfigParser.SafeConfigParser({"lang": "en"}) if is_local: self.config_file = os.path.join(bd.xdg_config_home, "periscope", "config") if not os.path.exists(self.config_file): folder = os.path.dirname(self.config_file) if not os.path.exists(folder): logging.info("Creating folder %s" %folder) os.mkdir(folder) logging.info("Creating config file") configfile = open(self.config_file, "w") self.config.write(configfile) configfile.close() else: #Load it self.config.read(self.config_file) self.pluginNames = self.listExistingPlugins() self._preferedLanguages = None Any help? Thanks guys.

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  • Silencing GCC warnings when using an "Uncopyable" class

    - by Kazade
    I have several classes that I don't want to be copyable, some of these classes have pointer data members. To make these classes uncopyable I privately inherit the following class template: template <class T> class Uncopyable { protected: Uncopyable() {} virtual ~Uncopyable() {} private: Uncopyable(const Uncopyable &); T & operator=(const T&); }; Which I used like so: class Entity : private Uncopyable<Entity> { } This works fine, however when I compile with -Weffc++ I still get the following warning: class Entity has pointer data members but does not override Entity(const Entity&) or operator=(const Entity&) Why is it still giving me this warning?

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  • Difficulty creating classes and arrays of those classes C#

    - by Lucifer Fayte
    I'm trying to implement a Discrete Fourier Transformation algorithm for a project I'm doing in school. But creating a class is seeming to be difficult(which it shouldn't be). I'm using Visual Studio 2012. Basically I need a class called Complex to store the two values I get from a DFT; The real portion and the imaginary portion. This is what I have so far for that: using System; using System.Collections.Generic; using System.Linq; using System.Text; using System.Threading.Tasks; namespace SoundEditor_V3 { public class Complex { public double real; public double im; public Complex() { real = 0; im = 0; } } } The problem is that it doesn't recognize the constructor as a constructor, now I'm just learning C#, but I looked it up online and this is how it's supposed to look apparently. It recognizes my constructor as a method. Why is that? Am I creating the class wrong? It's doing the same thing for my Fourier class as well. So each time I try to create a Fourier object and then use it's method...there is no such thing. example, I do this: Fourier fou = new Fourier(); fou.DFT(s, N, amp, 0); and it tells me fou is a 'field' but is used like a 'type' why is it saying that? Here is the code for my Fourier class as well: using System; using System.Collections.Generic; using System.Linq; using System.Text; using System.Threading.Tasks; namespace SoundEditor_V3 { public class Fourier { //FOURIER //N = number of samples //s is the array of samples(data) //amp is the array where the complex result will be written to //start is the where in the array to start public void DFT(byte[] s, int N, ref Complex[] amp, int start) { Complex tem = new Complex(); int f; int t; for (f = 0; f < N; f++) { tem.real = 0; tem.im = 0; for (t = 0; t < N; t++) { tem.real += s[t + start] * Math.Cos(2 * Math.PI * t * f / N); tem.im -= s[t + start] * Math.Sin(2 * Math.PI * t * f / N); } amp[f].real = tem.real; amp[f].im = tem.im; } } //INVERSE FOURIER public void IDFT(Complex[] A, ref int[] s) { int N = A.Length; int t, f; double result; for (t = 0; t < N; t++) { result = 0; for (f = 0; f < N; f++) { result += A[f].real * Math.Cos(2 * Math.PI * t * f / N) - A[f].im * Math.Sin(2 * Math.PI * t * f / N); } s[t] = (int)Math.Round(result); } } } } I'm very much stuck at the moment, any and all help would be appreciated. Thank you.

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  • NHibernate: discriminator without common base class?

    - by joniba
    Is it possible to map two classes to the same property without them sharing a common base class? For example, a situation like this: class Rule { public virtual int SequenceNumber { get; set; } public virtual ICondition Condition { get; set; } } interface ICondition { } class ExpressionCondition : ICondition { public virtual string Expression { get; set; } } class ThresholdCondition : ICondition { public virtual int Threshold { get; set; } } I also cannot add some empty abstract class that both conditions inherit from because the two ICondition implementations exist in different domains that are not allowed to reference each other. (Please no responses telling me that this situation should not occur in the first place - I'm aware of it and it doesn't help me.)

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  • Get class of caller's method (via inspect) in Python; or: super(Class,self).method() replacement wit

    - by Slava Vishnyakov
    Is it possible to get reference to class B in this example? class A(object): pass class B(A): def test(self): test2() class C(B): pass import inspect def test2(): frame = inspect.currentframe().f_back cls = frame.[?something here?] # cls here should == B (class) c = C() c.test() Basically, C is child of B, B is child of A. Then we create c of type C. Then the call to c.test() actually calls B.test() (via inheritance), which calls to test2(). test2() can get the parent frame frame; code reference to method via frame.f_code; self via frame.f_locals['self']; but type(frame.f_locals['self']) is C (of course), but not B, where method is defined. Any way to get B?

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  • How to generalize a method call in Java (to avoid code duplication)

    - by dln385
    I have a process that needs to call a method and return its value. However, there are several different methods that this process may need to call, depending on the situation. If I could pass the method and its arguments to the process (like in Python), then this would be no problem. However, I don't know of any way to do this in Java. Here's a concrete example. (This example uses Apache ZooKeeper, but you don't need to know anything about ZooKeeper to understand the example.) The ZooKeeper object has several methods that will fail if the network goes down. In this case, I always want to retry the method. To make this easy, I made a "BetterZooKeeper" class that inherits the ZooKeeper class, and all of its methods automatically retry on failure. This is what the code looked like: public class BetterZooKeeper extends ZooKeeper { private void waitForReconnect() { // logic } @Override public Stat exists(String path, Watcher watcher) { while (true) { try { return super.exists(path, watcher); } catch (KeeperException e) { // We will retry. } waitForReconnect(); } } @Override public byte[] getData(String path, boolean watch, Stat stat) { while (true) { try { return super.getData(path, watch, stat); } catch (KeeperException e) { // We will retry. } waitForReconnect(); } } @Override public void delete(String path, int version) { while (true) { try { super.delete(path, version); return; } catch (KeeperException e) { // We will retry. } waitForReconnect(); } } } (In the actual program there is much more logic and many more methods that I took out of the example for simplicity.) We can see that I'm using the same retry logic, but the arguments, method call, and return type are all different for each of the methods. Here's what I did to eliminate the duplication of code: public class BetterZooKeeper extends ZooKeeper { private void waitForReconnect() { // logic } @Override public Stat exists(final String path, final Watcher watcher) { return new RetryableZooKeeperAction<Stat>() { @Override public Stat action() { return BetterZooKeeper.super.exists(path, watcher); } }.run(); } @Override public byte[] getData(final String path, final boolean watch, final Stat stat) { return new RetryableZooKeeperAction<byte[]>() { @Override public byte[] action() { return BetterZooKeeper.super.getData(path, watch, stat); } }.run(); } @Override public void delete(final String path, final int version) { new RetryableZooKeeperAction<Object>() { @Override public Object action() { BetterZooKeeper.super.delete(path, version); return null; } }.run(); return; } private abstract class RetryableZooKeeperAction<T> { public abstract T action(); public final T run() { while (true) { try { return action(); } catch (KeeperException e) { // We will retry. } waitForReconnect(); } } } } The RetryableZooKeeperAction is parameterized with the return type of the function. The run() method holds the retry logic, and the action() method is a placeholder for whichever ZooKeeper method needs to be run. Each of the public methods of BetterZooKeeper instantiates an anonymous inner class that is a subclass of the RetryableZooKeeperAction inner class, and it overrides the action() method. The local variables are (strangely enough) implicitly passed to the action() method, which is possible because they are final. In the end, this approach does work and it does eliminate the duplication of the retry logic. However, it has two major drawbacks: (1) it creates a new object every time a method is called, and (2) it's ugly and hardly readable. Also I had to workaround the 'delete' method which has a void return value. So, here is my question: is there a better way to do this in Java? This can't be a totally uncommon task, and other languages (like Python) make it easier by allowing methods to be passed. I suspect there might be a way to do this through reflection, but I haven't been able to wrap my head around it.

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  • Checking lazy loaded properties have been instantiated

    - by PaulG
    In a class which has a lazy loaded property, such as: private Collection<int> someInts; public Collection<int> SomeInts { get { if (this.someInts == null) this.someInts = new Collection<int>(); return this.someInts; } } Is it worth also having a property such as: public bool SomeIntsExist { get { return (this.someInts != null && this.someInts.Count > 0); } } And then using that property.. eg: if (thatClass.SomeIntsExist) { // do something with thatClass.SomeInts collection } or is this premature optimisation. Its certainly easier to roll with something like below, but it will instantiate the collection needlessly: if (thatClass.SomeInts.Count > 0) { // do something with thatClass.SomeInts collection } Is the compiler smart enough to figure things like this out? Is there a better way?

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  • Android UnknownHost in asyncTask - loading web page

    - by Sneha
    I followed this tutorial for AsyncTask and getting the following error log: 03-23 11:44:42.936: WARN/System.err(315): java.net.UnknownHostException: www.google.co.in 03-23 11:44:42.936: WARN/System.err(315): at java.net.InetAddress.lookupHostByName(InetAddress.java:513) 03-23 11:44:42.936: WARN/System.err(315): at java.net.InetAddress.getAllByNameImpl(InetAddress.java:278) 03-23 11:44:42.936: WARN/System.err(315): at java.net.InetAddress.getAllByName(InetAddress.java:242) 03-23 11:44:42.936: WARN/System.err(315): at org.apache.http.impl.conn.DefaultClientConnectionOperator.openConnection(DefaultClientConnectionOperator.java:136) 03-23 11:44:42.936: WARN/System.err(315): at org.apache.http.impl.conn.AbstractPoolEntry.open(AbstractPoolEntry.java:164) 03-23 11:44:42.936: WARN/System.err(315): at org.apache.http.impl.conn.AbstractPooledConnAdapter.open(AbstractPooledConnAdapter.java:119) 03-23 11:44:42.936: WARN/System.err(315): at org.apache.http.impl.client.DefaultRequestDirector.execute(DefaultRequestDirector.java:348) 03-23 11:44:42.936: WARN/System.err(315): at org.apache.http.impl.client.AbstractHttpClient.execute(AbstractHttpClient.java:555) 03-23 11:44:42.936: WARN/System.err(315): at org.apache.http.impl.client.AbstractHttpClient.execute(AbstractHttpClient.java:487) 03-23 11:44:42.944: WARN/System.err(315): at org.apache.http.impl.client.AbstractHttpC lient.execute(AbstractHttpClient.java:465) 03-23 11:44:42.944: WARN/System.err(315): at com.test.async.AsyncTaskExampleActivity$DownloadWebPageTask.doInBackground (AsyncTaskExampleActivity.java:36) 03-23 11:44:42.944: WARN/System.err(315): at com.test.async.AsyncTaskExampleActivity$DownloadWebPageTask.doInBackground (AsyncTaskExampleActivity.java:1) 03-23 11:44:42.944: WARN/System.err(315): at android.os.AsyncTask$2.call(AsyncTask.java:185) 03-23 11:44:42.944: WARN/System.err(315): at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:305) 03-23 11:44:42.944: WARN/System.err(315): at java.util.concurrent.FutureTask.run (FutureTask.java:137) 03-23 11:44:42.944: WARN/System.err(315): at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1068) 03-23 11:44:42.944: WARN/System.err(315): at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:561) 03-23 11:44:42.944: WARN/System.err(315): at java.lang.Thread.run(Thread.java:1096) How do i fix it?? My Code: public class AsyncTaskExampleActivity extends Activity { private TextView textView; /** Called when the activity is first created. */ @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.main); textView = (TextView) findViewById(R.id.TextView01); } private class DownloadWebPageTask extends AsyncTask<String, Void, String> { @Override protected String doInBackground(String... urls) { String response = ""; Log.i("", "in doInBackgroundddddddddd.........."); Log.i("", "in readWebpageeeeeeeeeeeee"); /* * try { InetAddress i = * InetAddress.getByName("http://google.co.in"); } catch * (UnknownHostException e1) { e1.printStackTrace(); } */ for (String url : urls) { Log.i("", "in for looooooop doInBackgroundddddddddd.........."); DefaultHttpClient client = new DefaultHttpClient(); HttpGet httpGet = new HttpGet(url); try { Log .i("", "afetr for looooooop try doInBackgroundddddddddd.........."); HttpResponse execute = client.execute(httpGet); Log .i("", "afetr for looooooop try client ..execute doInBackgroundddddddddd.........."); InputStream content = execute.getEntity().getContent(); BufferedReader buffer = new BufferedReader( new InputStreamReader(content)); String s = ""; while ((s = buffer.readLine()) != null) { response += s; Log .i("", "afetr while looooooop try client ..execute doInBackgroundddddddddd.........."); } } catch (Exception e) { e.printStackTrace(); } } Log .i("", "afetr lasttttttttttttt b4 response doInBackgroundddddddddd.........."); return response; } @Override protected void onPostExecute(String result) { Log.i("", "in onPostExecuteeee.........."); textView.setText(result); } } public void readWebpage(View view) { /* * System.setProperty("http.proxyHost", "10.132.116.10"); * System.setProperty("http.proxyPort", "3128"); */ DownloadWebPageTask task = new DownloadWebPageTask(); task.execute(new String[] { "http://google.co.in" }); Log.i("", "in readWebpageeeeeeeeeeeee after execute.........."); } } main.xml: <Button android:id="@+id/readWebpage" android:layout_width="match_parent" android:layout_height="wrap_content" android:onClick="readWebpage" android:text="Load Webpage"> </Button> <TextView android:id="@+id/TextView01" android:layout_width="match_parent" android:layout_height="match_parent" android:text="Example Text"> </TextView> Manifest: <?xml version="1.0" encoding="utf-8"?> <manifest xmlns:android="http://schemas.android.com/apk/res/android" package="com.test.async" android:versionCode="1" android:versionName="1.0"> <uses-sdk android:minSdkVersion="8" /> <uses-permission android:name="android.permission.INTERNET"></uses-permission> <application android:icon="@drawable/icon" android:label="@string/app_name"> <activity android:name=".AsyncTaskExampleActivity" android:label="@string/app_name"> <intent-filter> <action android:name="android.intent.action.MAIN" /> <category android:name="android.intent.category.LAUNCHER" /> </intent-filter> </activity> </application> Thanks Sneha

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  • Loading a Windows DLL in Java and initiate a class from it

    - by Joy
    I have a Windows DLL file from .NET namely "System.Management.dll". I work with it using the code I write below: ManagementObjectSearcher searcher = new ManagementObjectSearcher("root\\CIMV2", "SELECT * FROM Win32_LogicalDisk WHERE Name = 'C:'"); foreach (ManagementObject queryObj in searcher.Get()) { Console.WriteLine("Win32_LogicalDisk instance: "); if (queryObj["VolumeSerialNumber"] != null) { Console.WriteLine("Drive Name : " + queryObj["Name"]); Console.WriteLine("VolumeSerialNumber:", queryObj["VolumeSerialNumber"]); SysdriveSerial = queryObj["VolumeSerialNumber"].ToString(); } } Now I need this piece of code to be in Java. So can I do this? Without anything like c++ unmanaged code. I don't want to use c++ unmanaged code to call to this dll. I want something like this : public class CallToCsharp { private static native void ManagementObjectSearcher(); public static void main(String[] args) { System.loadLibrary("System.Management"); System.out.println("Loaded"); ManagementObjectSearcher searcher = new ManagementObjectSearcher("root\\CIMV2", "SELECT * FROM Win32_LogicalDisk WHERE Name = 'C:'"); } }

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  • getResourceAsStream not loading resource

    - by Michal Gorecki
    The project that I am currently working on utilizes an old application contained within a .jar file. One of the responsibilities of this application is that it updates the database when changes to the configuration files are made. Every time I try to run this file (which is a simple Ant Task extension), I get an exception thrown early in the process. I decompiled the Java file responsible, and found that the exception being thrown happens here. I do not know what the issue is, as "hibernate.cfg.xml" is contained within the same .jar file as the .class throwing the exception. ClassLoader loader = Thread.currentThread().getContextClassLoader(); InputStream in = loader.getResourceAsStream("hibernate.cfg.xml"); if (in == null) { throw new RuntimeException("Couldn't find built in hibernate config"); } If anyone has any ideas, even pointing me in the right direction, I would be grateful. Of course, any solution will have to be external, as the client already has this build of the program in production use.

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