AbstractList addAll() method in Java with Examples
The addAll() method of java.util.AbstractList class is used to insert all of the elements in the specified collection into this list at the specified position.
- This shifts the element currently at that position (if any) and any subsequent elements to the right (increases their indices).
- The new elements will appear in this list in the order that they are returned by the specified collection’s iterator.
- The behavior of this operation is undefined if the specified collection is modified while the operation is in progress.
This implementation gets an iterator over the specified collection and iterates over it, inserting the elements obtained from the iterator into this list at the appropriate position, one at a time, using add(int, E). Many implementations will override this method for efficiency.
public boolean addAll(int index, Collection c)
Parameters: This method takes the following argument as a parameter.
- index- the index at which to insert the first element from the specified collection
- c- the collection containing elements to be added to this list
Return Value: This method returns true if this list changed as a result of the call.
- Exception: This method throws the following Exception.
- NullPointerException – if the specified collection contains one or more null elements and this list does not permit null elements, or if the specified collection is null
- IndexOutOfBoundsException – if the index is out of range (index size()).
Below are the examples to illustrate the addAll() method.
Original ArrayListlist : [A, B, C, D, E] ArrayList elements to be added : [X, Y, Z] Operation successful : true New ArrayList : [A, B, X, Y, Z, C, D, E]
Example 2: For NullPointerException
Original ArrayListlist : [A, B, C, D, E] ArrayList to be added : null Trying to get the null collection Exception thrown : java.lang.NullPointerException
Example 3: For IndexOutOfBoundsException
Original ArrayListlist : [A, B, C, D, E] ArrayList elements to be added : [X, Y, Z] Trying to put the out of range index Exception thrown : java.lang.IndexOutOfBoundsException: Index: -1, Size: 5
Attention reader! Don’t stop learning now. Get hold of all the important Java Foundation and Collections concepts with the Fundamentals of Java and Java Collections Course at a student-friendly price and become industry ready. To complete your preparation from learning a language to DS Algo and many more, please refer Complete Interview Preparation Course.