Java threads. Are they running at the same time?

Question

Hello everybody. I am implementing a multiagent system in java and at some point in the program i need a specific function (from a specific class) to run at the same time in several "copies". Those functions are communicating with each other with some messages, so as you can understand not running at the same time is a big problem because of this messages.
Below i am giving you an example of the code i am using. I would like your opinion whether those functions are running parallel or serial. If they are not running parallel what should i do? Any opinion or something that can help me would be perfect. Thanks in advance.
//my class
public class Agent extends Thread {
                       public void MinConflicts(Agent array[],int max_moves){//code in here}
public static void main(String[] args) throws IOException {
              Agent[] fbi = new Agent[num] //num is inserted by the user
             //code here
             for(i=0;i<num;i++){
                     fbi.start(); //starting the treads
for(i=0;i<num;i++){
fbi[i].MinConflicts(fbi,max_moves); //running the function that i want to run parallel
//code here also :)

Answer 1

What you appear to be doing here is creating an array of Thread references (which I hope at some point gets populated with actual Thread object references!)......because your first loop is wanting to cycle through each array slot starting the referenced Thread. Then the next loop iterates through the array again, this time calling the method for each Thread object.
Assuming that you do populate the array, what this code will do is start each Thread which, I believe, will start and immediately terminate because run() has not been over-ridden. The second loop winds up calling the method for each Thread in the array. You are actually calling it from the main thread though. So, as previously advised, I think that you will run each method sequentially.
The direction that I would head with this is to override run() in your agent Thread and have that run() method call the MiniConflicts() method. Then, in your main routine you can do away with the second for loop. The looping start will start all of the individual threads and they will execute the run() method......which in essence will be executing your MiniConflicts method.
This reply is NOT a total design... I am sure that there are holes to be filled... but I think that will get you headed in the right direction.