OnJava8-Examples/holding/AddingGroups.java

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//: holding/AddingGroups.java
// Adding groups of elements to Collection objects.
import java.util.*;
public class AddingGroups {
public static void main(String[] args) {
Collection<Integer> collection =
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new ArrayList<>(Arrays.asList(1, 2, 3, 4, 5));
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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.
}
} ///:~