OnJava8-Examples/collections/AddingGroups.java

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// collections/AddingGroups.java
// (c)2016 MindView LLC: see Copyright.txt
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// We make no guarantees that this code is fit for any purpose.
// Visit http://mindviewinc.com/Books/OnJava/ for more book information.
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// Adding groups of elements to Collection objects.
import java.util.*;
public class AddingGroups {
public static void main(String[] args) {
Collection<Integer> collection =
new ArrayList<>(Arrays.asList(1, 2, 3, 4, 5));
Integer[] moreInts = { 6, 7, 8, 9, 10 };
collection.addAll(Arrays.asList(moreInts));
// Runs significantly faster, but you can't
// construct a Collection this way:
Collections.addAll(collection, 11, 12, 13, 14, 15);
Collections.addAll(collection, moreInts);
// Produces a list "backed by" an array:
List<Integer> list = Arrays.asList(16, 17, 18, 19, 20);
list.set(1, 99); // OK -- modify an element
// list.add(21); // Runtime error because the
// underlying array cannot be resized.
}
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}