A HashMap is designed to build for only one purpose – hold key-value for a single threaded events. A map is very efficient for this purpose. However, you diverse from the fundamentals of why a HashMap exist, then you are charting into an extremely dangerous section of programming world – race condition, infinite loops that is basically Degeneration. <\/p>\n
Thus, a simple hashmay in multi-threaded environment will cause one time to spin out of control. To avoid such pain in production, use synchronized HashMap in all your applications.<\/p>\n
Refer to the blog post for the detail explanation on how a race condition in Hashmap can cause this issue of going into infinite loop.<\/p>\n