- java.util.LinkedList.addAll(Collection C): This method is used to append all of the elements from the collection passed as parameter to this function to the end of a list keeping in mind the order of return by the collections iterator.
Syntax:
boolean addAll(Collection C)
Parameters: The parameter C is a collection of ArrayList. It is the collection whose elements are needed to be appended at the end of the list.
Return Value: The method returns true if at least one action of append is performed.
Below program illustrate the Java.util.LinkedList.addAll() method:
// Java code to illustrate boolean addAll()importjava.util.*;importjava.util.LinkedList;importjava.util.ArrayList;ÂÂpublicclassLinkedListDemo {  Âpublicstaticvoidmain(String args[]) {     Â// Creating an empty LinkedList     ÂLinkedList<String> list =newLinkedList<String>();     Â// Use add() method to add elements in the list     Âlist.add("Geeks");     Âlist.add("for");     Âlist.add("Geeks");     Âlist.add("10");     Âlist.add("20");      Â     Â// A collection is created     ÂCollection<String> collect =newArrayList<String>();     Âcollect.add("A");     Âcollect.add("Computer");     Âcollect.add("Portal");     Âcollect.add("for");     Âcollect.add("Geeks");     Â// Displaying the list     ÂSystem.out.println("The LinkedList is: "+ list);            Â     Â// Appending the collection to the list     Âlist.addAll(collect);    Â// Clearing the list using clear() and displaying    ÂSystem.out.println("The new linked list is: "+ list);  Â}}Output:The LinkedList is: [Geeks, for, Geeks, 10, 20] The new linked list is: [Geeks, for, Geeks, 10, 20, A, Computer, Portal, for, Geeks]
- java.util.LinkedList.addAll(int index, Collection C): This method is used to append all of the elements from the collection passed as parameter to this function at a specific index or position of a list.
Syntax:
boolean addAll(int index, Collection C)
Parameters: This function accepts two parameters as shown in the above syntax and are described below.
- index: This parameter is of integer datatype and specifies the position in the list starting from where the elements from the container will be inserted.
- C: It is a collection of ArrayList. It is the collection whose elements are needed to be appended.
Return Value: The method returns TRUE if at least one action of append is performed.
Below program illustrate the Java.util.LinkedList.addAll() method:
// Java code to illustrate boolean addAll()importjava.util.*;importjava.util.LinkedList;importjava.util.ArrayList;ÂÂpublicclassLinkedListDemo {  Âpublicstaticvoidmain(String args[]) {     Â// Creating an empty LinkedList     ÂLinkedList<String> list =newLinkedList<String>();     Â// Use add() method to add elements in the list     Âlist.add("Geeks");     Âlist.add("for");     Âlist.add("Geeks");     Âlist.add("10");     Âlist.add("20");      Â     Â// Creating a Collection     ÂCollection<String> collect =newArrayList<String>();     Âcollect.add("A");     Âcollect.add("Computer");     Âcollect.add("Portal");     Âcollect.add("for");     Âcollect.add("Geeks");     Â// Displaying the list     ÂSystem.out.println("The LinkedList is: "+ list);            Â     Â// Appending the collection to the list     Âlist.addAll(1, collect);    Â// Clearing the list using clear() and displaying    ÂSystem.out.println("The new linked list is: "+ list);  Â}}Output:The LinkedList is: [Geeks, for, Geeks, 10, 20] The new linked list is: [Geeks, A, Computer, Portal, for, Geeks, for, Geeks, 10, 20]
LinkedList addAll() Method in Java
