In Java, you can list all threads currently running in your program by using the Thread class's getAllStackTraces() method, which returns a map of all active threads and their stack traces.

Here's an example code snippet that demonstrates how to list all threads currently running in Java:

import java.util.Map;

public class ListThreadsExample {
    public static void main(String[] args) {
        Map<Thread, StackTraceElement[]> threadMap = Thread.getAllStackTraces();
        for (Map.Entry<Thread, StackTraceElement[]> entry : threadMap.entrySet()) {
            Thread thread = entry.getKey();
            System.out.println("Thread name: " + thread.getName());
            System.out.println("Thread state: " + thread.getState());
            for (StackTraceElement element : entry.getValue()) {
                System.out.println("\tat " + element);
            }
            System.out.println();
        }
    }
}

In this example, we first use the Thread.getAllStackTraces() method to get a map of all active threads and their stack traces. We then iterate over the entries in the map and print information about each thread, including its name, state, and stack trace.

Note that the Thread.getAllStackTraces() method returns a map of type Map<Thread, StackTraceElement[]>, where each key is a Thread object, and each value is an array of StackTraceElement objects that represents the current stack trace of the thread.