Concurrent collections
Multi-threaded environments are important for performance, but in any multi-threaded environment, data integrity becomes an issue to consider. Imagine a situation where you have several threads interacting with a shared data structure, such as an ArrayList or HashMap. While one thread might be trying to read data from the structure, another could be writing to it. This can lead to data inconsistency and other types of errors.
One common problem that arises in such situations is known as a concurrent modification exception. This occurs when one thread is iterating over a data structure, and another thread attempts to modify it. Java recognizes that this can cause inconsistencies and throws an exception to prevent this dangerous operation.
Consider the following example, where a HashMap is being used:
Map<String, String> languageMap = new HashMap<>();languageMap.put("Maaike", "Java");
languageMap.put("Seán"...
