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Questions tagged [callable]

A task that returns a result and may throw an exception.

The Callable interface is similar to Runnable, in that both are designed for classes whose instances are potentially executed by another thread. A Runnable, however, does not return a result and cannot throw a checked exception.

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The difference between the Runnable and Callable interfaces in Java

What is the difference between using the Runnable and Callable interfaces when designing a concurrent thread in Java, why would you choose one over the other?
Scottm
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What is a "callable"?

Now that it's clear what a metaclass is, there is an associated concept that I use all the time without knowing what it really means. I suppose everybody made once a mistake with parenthesis, resulting in an "object is not callable" exception.…
e-satis
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TypeError: 'list' object is not callable while trying to access a list

I am trying to run this code where I have a list of lists. I need to add to inner lists, but I get the error TypeError: 'list' object is not callable. Can anyone tell me what am I doing wrong here. def createlists(): global maxchar global…
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How to use Callable with void return type?

I am working on a project in which I have multiple interface and two Implementations classes which needs to implement these two interfaces. Suppose my first Interface is - public Interface interfaceA { public void abc() throws Exception; } And…
AKIWEB
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What's the difference between Future and FutureTask in Java?

Since use ExecutorService can submit a Callable task and return a Future, why need to use FutureTask to wrap Callable task and use the method execute? I feel they both do the same thing.
Hesey
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Is there a way to take an argument in a callable method?

I have created a piece of code which takes an IP address (from main method in another class) and then loops through a range of IP addresses pinging each one as it goes. I have a GUI front end on this and it was crashing (hence why I've done the…
DMo
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Odd method call in java using a dot operator to access a generic list

I came across some advanced java code (advanced for me :) ) I need help understanding. In a class there is a nested class as below: private final class CoverageCRUDaoCallable implements Callable> { private final…
Horse Voice
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When to use Spring @Async vs Callable controller (async controller, servlet 3)

I would like to know the general use case of using @Async and Servlet 3 asynchronous request implementation in Spring using Callable. As I understand, @Async is for making any method (specifically, any service method) execute…
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Difference between Spring MVC's @Async, DeferredResult and Callable

I've a long-running task defined in a Spring service. It is started by a Spring MVC controller. I want to start the service and return back an HttpResponse to the caller before the service ends. The service saves a file on file system at end. In…
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Where to catch Exceptions thrown from Callable.call()

Possible Duplicate: Handling exceptions from Java ExecutorService tasks I use the ExecutorService from Java for coordinating Threads. For starting the threads I use pool = new ExecutorService(2); callableResults = pool.invokeAll(threads); To…
nano7
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What is a callable object in C++?

I'm currently studying boost threads. And I came across that the thread class has a constructor that accepts callable objects. What are callable objects? class CallableClass { private: // Number of iterations int m_iterations; public: …
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What is the difference between a function object and a callable object?

I recently saw the presentation about the changes in ECMAScript 5. And there was a slide with this statement: Function vs Callable typeof f === 'function' // → f is Callable ({}).toString.call(f) === '[object Function]' // → f…
Gumbo
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How to pass a parameter to Scikit-Learn Keras model function

I have the following code, using Keras Scikit-Learn Wrapper, which work fine: from keras.models import Sequential from keras.layers import Dense from sklearn import datasets from keras.wrappers.scikit_learn import KerasClassifier from…
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RestTemplate should be static globally declared?

I am using Java Callable Future in my code. Below is my main code which uses the future and callables - public class TimeoutThread { public static void main(String[] args) throws Exception { ExecutorService executor =…
AKIWEB
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Java: Parameterized Runnable

Standard Runnable interface has only non-parametrized run() method. There is also Callable interface with call() method returning result of generic type. I need to pass generic parameter, something like this: interface MyRunnable { public…
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