java.util.Map.computeIfAbsent(key, Function) The method Map.computeIfAbsent(key, Function) computes the new value and associates it with the key if there is no mapping for the given key or the mapping is null. Returns the new value associated with the key.
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java.util.Map.compute(Key, BiFunction) The method Map.compute(Key, BiFunction) returns the new value associated with the specified key. The value is computed using the given function.
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