(Yes)
Thread-safety is a property of an object or code which guarantees that if executed or used by multiple thread in any manner e.g. read vs write it will behave as expected. For example, a thread-safe counter object will not miss any count if same instance of that counter is shared among multiple threads. Apparently, you can also divide collection classes in two category, thread-safe and non-thread-safe. Vector is indeed a thread-safe class and it achieves thread-safety by synchronizing methods which modifies state of Vector, on the other hand, its counterpart ArrayList is not thread-safe.
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