The removeAll() method of java.util.TreeSet class is used to remove from this set all of its elements that are contained in the specified collection.
public boolean removeAll(Collection c)
Parameters: This method takes collection c as a parameter containing elements to be removed from this set.
Returns Value: This method returns true if this set changed as a result of the call.
Exception: This method throws NullPointerException if this set contains a null element and the specified collection does not permit null elements (optional), or if the specified collection is null.
Below are the examples to illustrate the removeAll() method.
TreeSet before removeAll() operation : [1, 2, 3, 4, 5] Collection Elements to be removed : [1, 2, 3] TreeSet after removeAll() operation : [4, 5]
Example 2: For NullPointerException
TreeSet before removeAll() operation : [1, 2, 3, 4, 5] Collection Elements to be removed : null Trying to pass null as a specified element Exception thrown : java.lang.NullPointerException
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