add toArray(int[])

primitiveCollections/src/main/java/org/lucares/collections/IntList.java

@@ -20,12 +20,13 @@ public final class IntList implements Serializable, Cloneable {
 	// TODO support sublists
 	// TODO add retainAll
 	// TODO add removeAll
+	// TODO add retainAll for sorted lists
+	// TODO add removeAll for sorted lists
 	// TODO add removeIf
 	// TODO add removeRange
 	// TODO add replace
 	// TODO add lastIndexOf
 	// TODO add indexOf
-	// TODO add toArray(int[] a)
 	// TODO remove bounds checks that are handled by java, e.g. negative indices
 	// TODO toString
 
@@ -152,6 +153,7 @@ public final class IntList implements Serializable, Cloneable {
 
 		ensureCapacity(values.length);
 
+		// TODO do not copy the array twice
 		final int[] newData = new int[data.length];
 		System.arraycopy(data, 0, newData, 0, pos);
 		System.arraycopy(values, 0, newData, pos, values.length);
@@ -282,6 +284,15 @@ public final class IntList implements Serializable, Cloneable {
 		return get(0, index);
 	}
 
+	public int[] toArray(final int[] input) {
+
+		if (input.length < index) {
+			return toArray();
+		}
+		System.arraycopy(data, 0, input, 0, index);
+		return input;
+	}
+
 	/**
 	 * Sorts the list into ascending order.
 	 */
@@ -451,4 +462,5 @@ public final class IntList implements Serializable, Cloneable {
 			throw new IllegalStateException(e);
 		}
 	}
+
 }

primitiveCollections/src/test/java/org/lucares/collections/IntListTest.java

@@ -285,6 +285,59 @@ public class IntListTest {
 		Assert.assertArrayEquals(actual, new int[0]);
 	}
 
+	@Test
+	public void testToArray() {
+		final IntList list = new IntList();
+		list.addAll(1, 2, 3, 4, 5, 6);
+
+		{
+			final int[] input = new int[1];
+			final int[] actual = list.toArray(input);
+			// input is too short -> new array returned
+			Assert.assertNotSame(input, actual);
+			Assert.assertArrayEquals(list.toArray(), actual);
+		}
+
+		{
+			final int[] input = new int[list.size()];
+			final int[] actual = list.toArray(input);
+			// input fits exactly -> input returned
+			Assert.assertSame(input, actual);
+			Assert.assertArrayEquals(list.toArray(), actual);
+		}
+
+		{
+			final int[] input = new int[list.size() + 1];
+			final int[] expected = { 1, 2, 3, 4, 5, 6, 0 };
+			final int[] actual = list.toArray(input);
+			// input too big -> input returned
+			Assert.assertSame(input, actual);
+			Assert.assertArrayEquals(expected, actual);
+		}
+	}
+
+	@Test
+	public void testToArrayWithEmptyList() {
+		final IntList list = new IntList();
+
+		{
+			final int[] input = new int[0];
+			final int[] actual = list.toArray(input);
+			// input fits exactly -> input returned
+			Assert.assertSame(input, actual);
+			Assert.assertArrayEquals(list.toArray(), actual);
+		}
+
+		{
+			final int[] input = new int[list.size() + 1];
+			final int[] expected = { 0 };
+			final int[] actual = list.toArray(input);
+			// input too big -> input returned
+			Assert.assertSame(input, actual);
+			Assert.assertArrayEquals(expected, actual);
+		}
+	}
+
 	@Test
 	public void testRemove() {
 		final IntList list = new IntList();