我如何从mongodb集合中获取条件数据并将其存储在arraylist <object> java中

Question

我需要使用Java MongoCollection返回“伦敦”的客户列表。我的收藏如下：

asyncio

我试图返回一个DBcursor列表，但是我无法从中获取值

import time
from multiprocessing import Process

def procManager(f,a,o):
    print(f"{o} started at {time.strftime('%X')}")
    p = Process(target=f, args=(a,))
    p.start()
    # p.join()
    print(f"{o} finished at {time.strftime('%X')}") # This will occur immediately
    print("=========")

def community(cg):
    for i in range(10):
        print("%s - %s" %(cg, i))
        time.sleep(1)

procManager(community, "This is A", "A")
procManager(community, "This is B", "B")