按启动顺序获得线程的结果

Question

I am accessing data from an api with the below mentioned endpoints:-

1.getProductList
2.getImageurlofProduct/productid

I am supposed to create an arraylist of hashmaps which contain productid,productprice and productimageurl of each product.From the main thread I spawn a thread-A to the first endpoint and as I parse through the result I spawn threads from thread A.

However the sequence in which those threads respond back to threadA is not the same in which they were started. So i end up having the imageurl of product 2 added up to product with id 1.

How do i handle this. An algorithm should do fine for me. Please let me know if you want me to clarify something more

Answer 1

If you use an Executor to spawn your threads, you can save all the returned Future s and then call Future.get() on them in the same order as they were started.

Read more here: ExecutorService and Future .