你如何在java中创建多线程函数？

Question

My project asked me to create a multithreading function, and it allows up to 1000 threads. How do you do that in java?

I know we can do that by implementing the Runnable interface or creating a subclass to extends Thread , but I don't know if you can create such a large number of threads.

Answer 1

try this

import java.awt.Component;
import java.awt.event.ActionListener;
import javax.swing.JButton;
import javax.swing.JFrame;
public class main {
private static JFrame frame;
private static JButton button;
main(){
    frame = new JFrame();
    button = new JButton("Click");
    button.setBounds(20,20,2,2);
    button.addActionListener(multi(frame));
    frame.setSize(200,200);
    frame.add(button);
    frame.setVisible(true);
}
    public static void main(String[] args) {
        new main();
    }
    private static ActionListener multi (Component GTOS) {
        return (ae) -> {
            new Thread(() -> {
                System.out.println("test");
            }).start();
        };
    }
}

Answer 2

Look at the ExecutorService . For example, it might look like this:

public void myMethod() {
    ExecutorService executor = Executors.newFixedThreadPool(1000);
    List<Callable<Boolean>> callableList = new ArrayList<Callable<Boolean>>();      
    // any list for init our threads
    for (int i = 0; i < 1000; i++)
        callableList.add(() -> exec()); 
    executor.invokeAll(callableList);
}

public boolean exec() {
    // do something
    return true;
}

Answer 3

This code isn't great for a number of reasons, but it does show you a way to create 1,000 threads:

for (int n = 0; n < 1000; n++) {
    new Thread("thread " + n).start();
}