runnable

This question already has an answer here: Convert String to Code 18 answers How to compile .java file from within java program [duplicate] 3 answers Is there a way to run a string as code? I mean if I had a string run having value System.out.println("Hello World) could I run the string as normal code the then output will be Hello World? For Example: String code = "System.out.println("Hello World)"; code.run(); //I know this doesn't work Console: Hello World aliteralmind You want the equivalent of JavaScript's eval . There is no equivalent in Java. Well, there is but it's not trivial. You can

I know there are already a lot of questions like this but I don't see what I'm doing wrong. The app crashes without anything shown. Also, the error doesn't occur on my device or emulator. Just on some devices (say 30-40%?). Can't create handler inside thread that has not called Looper.prepare() MainActivity.java public class MainActivity extends Activity implements Runnable { Gebruiker gebruiker = new Gebruiker(); private DatabaseHelper db; Context context; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main);

if i have got such java code: public static void main(String[] args) { for(int i = 0;i<100;i++) { Future<?> f = ThreadPoolManager.getInstance().schedule(new START(), 500); f.cancel(true); } } private class START implements Runnable { @Override public void run() { System.out.println(1); } } And run it in debug, i can see that all of those threads(after cancel) are still running, so are they taking my memory too? And if yes, how can i destroy those Threads completely? cancel(true) calls interrupt() on your thread, nothing more. So, you need to handle it properly in your run() method. For your

I want to use concurrency in Java to make requests to an online API, download and parse the response documents, and load the resulting data into a database. Is it standard to have one pool of threads in which each thread requests, parses, and loads? In other words, only one class implements Runnable . Or is it more efficient to have, say, three different pools of threads, with the first pool of threads making the requests and pushing them to a queue, the second pool of threads polling from the first queue, parsing, and pushing the parsed data to a second queue, and finally the third pool

A very fundamental question. The documentation mentions that all methods in QNetworkAccessManager are reentrant. If so, is performing a get() method in a QRunnable without locks legal? My code would look something like this: class MyClass: public QRunnable { void run() { ... QNetworkAccessManager nam; QNetworkReply* reply = name.get(request) // No Read-write lock. ... } }; From the Qt documentation : [...] a class is said to be reentrant if its member functions can [simultaneously] be called safely from multiple threads, as long as each thread uses a different instance of the class. Since you