How to declare an ArrayList with values

Question

ArrayList or List declaration in Java has questioned and answered how to declare an empty ArrayList but how do I declare an ArrayList with values   I ve tried the following but it returns a syntax error   import java io IOException  import java util ArrayList   public class test       public static void main String   args  throws IOException           ArrayList lt String gt  x   new ArrayList lt String gt             x     xyz    abc

User · Accepted Answer

In Java 9  you can do   var x   List of  xyz    abc        var  works only for local variables     Java 8 using Stream   Stream of  xyz    abc   collect Collectors toList         And of course  you can create a new object using the constructor that accepts a Collection   List lt String gt  x   new ArrayList lt  gt  Arrays asList  xyz    abc         Tip  The docs contains very useful information that usually contains the answer you re looking for  For example  here are the constructors of the ArrayList class    ArrayList       Constructs an empty list with an initial capacity of ten   ArrayList Collection lt   extends E gt  c          Constructs a list containing the elements of the specified collection  in the order they are returned by the collection s iterator   ArrayList int initialCapacity      Constructs an empty list with the specified initial capacity

User · Answer

Use this one    ArrayList lt String gt  x   new ArrayList Arrays asList  abc    mno

User · Answer

Try this   List lt String gt  x   new ArrayList lt String gt  Arrays asList  xyz    abc       It s a good practice to declare the ArrayList with interface List if you don t have to invoke the specific methods

User · Answer

Use   List lt String gt  x   new ArrayList lt  gt  Arrays asList  xyz    abc       If you don t want to add new elements to the list later  you can also use  Arrays asList returns a fixed-size list    List lt String gt  x   Arrays asList  xyz    abc      Note  you can also use a static import if you like  then it looks like this   import static java util Arrays asList         List lt String gt  x   new ArrayList lt  gt  asList  xyz    abc       or  List lt String gt  x   asList  xyz    abc

User · Answer

The Guava library contains convenience methods for creating lists and other collections which makes this much prettier than using the standard library classes   Example   ArrayList lt String gt  list   newArrayList  a    b    c       This assumes import static com google common collect Lists newArrayList

User · Answer

You can do like this    List lt String gt  temp   new ArrayList lt String gt  Arrays asList  1    12

[java] How to declare an ArrayList with values?

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