rnrneverdies's questions

I need to get the attribute urlof all the elements <media:content/>of an XML similar to this.

<rss version='2.0' xmlns:media='http://search.yahoo.com/mrss/'>
    <channel>
        <item>
            <media:group>
                <media:content url='https://valor'/>
            </media:group>
        </item>
        <item>
            <media:group>
                <media:content url='https://valor'/>
            </media:group>
        </item>    
    </channel>
</rss>

This is a method I tried, but it contents.getLength()returns zero.

DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();
DocumentBuilder builder = factory.newDocumentBuilder();

Document doc = builder.parse(inputStream);
NodeList contents = doc.getElementsByTagNameNS("http://search.yahoo.com/mrss/", "content");

I've tried using XPath... again it contents.getLength()returns zero.

XPathFactory factory2 = XPathFactory.newInstance();
XPath xpath = factory2.newXPath();
// XPathExpression expr = xpath.compile("//content"); 
XPathExpression expr = xpath.compile("//*[name()='content']");
NodeList contents = (NodeList) expr.evaluate(doc, XPathConstants.NODESET);

I never get the required nodes, any suggestions?

I have a case, which is not the first time I have faced, and I would like a code review.

The issue is that I have a task, which must be run from time to time X (not exactly X, precision is desirable but not mandatory, an approximation is fine).

What I usually do is the following:

class Servicio implements Runnable {

    private volatile boolean running = true;

    @Override
    void run() {
        while(this.isRunning()) {
            try { 
                // operaciones I/O y procesamiento

                // Espero el tiempo X
                Thread.sleep(1000);
            } catch (InterruptedException ie) {
               // no hago nada, que de vez en cuando el ciclo se ejecute
               // de forma no muy precisa no es un problema. 
            } catch (otras excepciones que me interesa atrapar) {
               // quizá stopRunning(), quizá no
               // ya que las partes de I/O tienen retry polices,
               // pero si por ejemplo recibo File Not Found o 404, no quiero seguir.
            } 
        }
    }

    public synchronized void stopRunning() {
       this.running = false;
    }

    public synchronized boolean isRunning() {
       return this.running;
    }
}

Additionally, stopRunning()it can be called from another thread.

Ask:

What alternative design can I use? What are the advantages / disadvantages of this method compared to the proposed method?

I'm doing maintenance on a legacy system, and I've seen in many places a block similar to the following:

try {
  // aqui codigo

} finally {
  // mas codigo aqui
}

My question is: What is the function of making a try .. finally, without the block catch?

I am trying to compile a nodejs project , with VS2015.

The main project has sub projects in sub folders, that is to say that in each sub-folder there is one package.jsonwith its own code and each one declares the dependencies to the other projects.

The problem I have is that when I try to run any example from the main project, instead of using the packages from the sub-folders, it downloads all the packages from the npm registry .

My question is: How can I configure visual studio to use the code of the sub-projects without downloading the packages from the internet?

Is there any specific technical difference in between doing this...

using OtraLibreria;
namespace Libreria {
  class MiClase {
     /// mas código aqui
  }
}

and this other?

namespace Libreria {
  using OtraLibreria;
  class MiClase {
     /// mas código aqui
  }
}

Today I found a piece of code where the program seems to have a bug, but works as expected:

This is a simplification of that code, which reproduces the same behavior:

int main()
{
  int arreglo[] = { 0, 1, 2, 3 };
  int indice = 0;
  std::cout << arreglo[indice] << "\n";
  indice++;
  std::cout << arreglo[indice] << "\n";
  indice++;
  std::cout << indice[arreglo] << "\n";
  indice++;
  std::cout << arreglo[indice] << "\n";
}

Departure:

$ ./prueba
0
1
2
3

The question is: Why does the expression work indice[arreglo]as if I were putting arreglo[indice], if they should be backwards?

In the company I work for, if a member of the development team proposes to use an Open Source library to solve a problem , the project producers always ask what software license comes with the library.

We are not lawyers, but I understand that not all the different licenses can be combined because there are certain requirements that each one requires.

That said, I want to know, what would be the considerations to take into account before including an Open Source library in a software that I created on my own ?

I just realized that I made one committhat includes a password. The problem is that I already uploaded the changes to the source repository.

How can I repair it without losing the changes I made and without leaving the password in the repository history?