Passing a list as argument to a vararg method

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In Java, a vararg method is a method that can take a varying number of arguments of the same type. To pass a list as an argument to a vararg method, you can convert the list to an array and then pass the array as the vararg argument.

Here is an example:

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public static void doSomething(String... args) {
    // code here
}

List<String> myList = new ArrayList<>();
    myList.add("arg1");
    myList.add("arg2");
    myList.add("arg3");

doSomething(myList.toArray(new String[0]));

In this example, the doSomething method takes a vararg argument of type String. We create a list of strings and add three elements to it. To pass this list as an argument to doSomething, we first convert the list to an array using the toArray method of ArrayList and then pass this array as the vararg argument to doSomething.

Note that we pass an empty array as an argument to the toArray method. This is because the size of the resulting array is determined by the size of the list, and we do not know this in advance. By passing an empty array, the toArray method creates a new array of the correct size.