How to pass an ArrayList to a varargs method parameter?

Source article: Passing a list as an argument to a vararg method

Use the toArray(T[] arr) method.

.getMap(locations.toArray(new WorldLocation[0]))

Here's a complete example:

public static void method(String... strs) {
    for (String s : strs)
        System.out.println(s);
}

...
    List<String> strs = new ArrayList<String>();
    strs.add("hello");
    strs.add("world");
    
    method(strs.toArray(new String[0]));
    //     ^^^^^^^^^^^^^^^^^^^^^^^^^^^
...

In Java 8:

List<WorldLocation> locations = new ArrayList<>();

.getMap(locations.stream().toArray(WorldLocation[]::new));

A shorter version of the accepted answer using Guava:

.getMap(Iterables.toArray(locations, WorldLocation.class));

can be shortened further by statically importing toArray:

import static com.google.common.collect.toArray;
// ...

    .getMap(toArray(locations, WorldLocation.class));