我尝试将 Getting-started Akka 教程从 Scala 转换为 Java，并用线程替换 actor。
该教程可以在这里找到http://typesafe.com/resources/tutorials/getting-started-with-akka-scala.html
可以从 Typesafe giter8 模板存储库中签出原始 Pi.scala 文件
g8 typesafehub/akka-first-tutorial-scala
我想知道我所做的是否正确。
这是我的 Pi.java
import java.util.ArrayList;
import java.util.List;
import java.util.concurrent.*;
public class Pi {
/**
* @param args
*/
public static void main(String[] args) {
// TODO Auto-generated method stub
Listener listener = new Listener();
//calculate(nrOfWorkers = 10, nrOfElements = 10000, nrOfMessages = 10000)
Master master = new Master(4, 1000, 1000, listener);
master.calculate();
}
}
class Worker implements Callable<Double> {
private int start;
private int nrOfElements;
public Worker(int start, int nrOfElements) {
this.start = start;
this.nrOfElements = nrOfElements;
}
@Override
public Double call() throws Exception {
double acc = 0.0;
for(int i = start; i < start + nrOfElements; i++) {
acc += 4.0 * (1 - (i % 2) * 2) / (2 * i + 1);
}
return acc;
}
}
class Listener {
public void PiApproximation(double pi, long duration) {
System.out.println(String.format("\n\tPi approximation: \t\t%s\n\tCalculation time: \t%s", pi, duration));
}
}
class Master {
private double pi = 0.0;
private int nrOfResults = 0;
private final long start = java.lang.System.currentTimeMillis();
private int nrOfWorkers;
private int nrOfMessages;
private int nrOfElements;
private Listener listener;
private ExecutorService executor;
public Master(int nrOfWorkers,
int nrOfMessages,
int nrOfElements,
Listener listener) {
this.nrOfWorkers = nrOfWorkers;
this.nrOfMessages = nrOfMessages;
this.nrOfElements = nrOfElements;
this.listener = listener;
//Round robin scheduling is not enforced here as in akka.
executor = Executors.newFixedThreadPool(nrOfWorkers);
}
public void calculate() {
List<Future<Double>> list = new ArrayList<Future<Double>>();
for (int i = 0; i < nrOfMessages; i++) {
Callable<Double> worker = new Worker(i * nrOfElements, nrOfElements);
Future<Double> submit = executor.submit(worker);
list.add(submit);
}
for (Future<Double> future : list) {
try {
pi += future.get();
}
catch (InterruptedException e) { e.printStackTrace(); }
catch (ExecutionException e) { e.printStackTrace(); }
}
//send results to listener
listener.PiApproximation(pi, java.lang.System.currentTimeMillis() - start);
executor.shutdown();
}
}