use fromIndex and toIndex for remove instead of from and length

The new API is consistent with the internal API of ArrayList.

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

@@ -198,31 +198,31 @@ public class IntList implements Serializable, Cloneable {
 	/**
 	 * Removes elements from the list.
 	 *
-	 * @param from
+	 * @param fromIndex
 	 *            index of the first element to remove
-	 * @param length
-	 *            number of elements to remove
+	 * @param toIndex
+	 *            the index of the last element to remove (exclusive)
 	 * @throws IndexOutOfBoundsException
-	 *             if {@code from} or {@code length} is negative, or if the range
-	 *             defined by {@code from} and {@code length} is out of bounds
+	 *             if {@code fromIndex} or {@code toIndex} is negative, or if the
+	 *             range defined by {@code fromIndex} and {@code toIndex} is out of
+	 *             bounds
 	 */
-	public void remove(final int from, final int length) {
+	public void remove(final int fromIndex, final int toIndex) {
 
-		if (from < 0) {
-			throw new IndexOutOfBoundsException("from must not be negative, but was: " + from);
+		if (fromIndex < 0) {
+			throw new IndexOutOfBoundsException("from must not be negative, but was: " + fromIndex);
 		}
-		if (length < 0) {
-			throw new IndexOutOfBoundsException("length must not be negative, but was: " + length);
+		if (toIndex < fromIndex) {
+			throw new IndexOutOfBoundsException("toIndex must not be smaller than fromIndex, but was: " + toIndex);
 		}
-		if (from + length > index) {
-			throw new IndexOutOfBoundsException("from: " + from + " length: " + length);
+		if (toIndex > index) {
+			throw new IndexOutOfBoundsException("from: " + fromIndex + " toIndex: " + toIndex);
 		}
 
-		final int[] newData = new int[data.length];
-		System.arraycopy(data, 0, newData, 0, from);
-		System.arraycopy(data, from + length, newData, from, data.length - from - length);
-		data = newData;
-		index -= length;
+		final int numRemoved = index - toIndex;
+		System.arraycopy(data, toIndex, data, fromIndex, numRemoved);
+
+		index = index - (toIndex - fromIndex);
 	}
 
 	/**

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

@@ -295,25 +295,31 @@ public class IntListTest {
 
 		list.addAll(ints);
 
-		list.remove(2, 0);
+		// remove nothing
+		list.remove(2, 2);
 		Assert.assertArrayEquals(ints, list.toArray());
 
-		list.remove(9, 1);
+		// remove the last element
+		list.remove(9, 10);
 		final int[] expectedA = removeElements(ints, 9);
 		Assert.assertArrayEquals(expectedA, list.toArray());
 
+		// remove the first element
 		list.remove(0, 1);
 		final int[] expectedB = removeElements(expectedA, 0);
 		Assert.assertArrayEquals(expectedB, list.toArray());
 
-		list.remove(7, 1);
-		final int[] expectedC = removeElements(expectedB, 7);
+		// remove single element in the middle
+		list.remove(3, 4);
+		final int[] expectedC = removeElements(expectedB, 3);
 		Assert.assertArrayEquals(expectedC, list.toArray());
 
-		list.remove(3, 3);
-		final int[] expectedD = removeElements(expectedC, 3, 4, 5);
+		// remove several elements in the middle
+		list.remove(2, 5);
+		final int[] expectedD = removeElements(expectedC, 2, 3, 4);
 		Assert.assertArrayEquals(expectedD, list.toArray());
 
+		// remove all elements
 		list.remove(0, 4);
 		final int[] expectedE = removeElements(expectedD, 0, 1, 2, 3);
 		Assert.assertArrayEquals(expectedE, list.toArray());
@@ -332,19 +338,19 @@ public class IntListTest {
 			// expected
 		}
 		try {
-			list.remove(1, -1);
+			list.remove(1, 0);
 			Assert.fail();
 		} catch (final IndexOutOfBoundsException e) {
 			// expected
 		}
 		try {
-			list.remove(3, 2);
+			list.remove(3, 5);
 			Assert.fail();
 		} catch (final IndexOutOfBoundsException e) {
 			// expected
 		}
 		try {
-			list.remove(4, 1);
+			list.remove(4, 5);
 			Assert.fail();
 		} catch (final IndexOutOfBoundsException e) {
 			// expected
@@ -387,7 +393,7 @@ public class IntListTest {
 		Assert.assertEquals(a.hashCode(), b.hashCode());
 
 		// change one value
-		a.remove(2, 1);
+		a.remove(2, 3);
 		a.insert(2, 99);
 		Assert.assertFalse(a.equals(b));
 		Assert.assertNotEquals(a.hashCode(), b.hashCode());
@@ -404,9 +410,9 @@ public class IntListTest {
 		Assert.assertArrayEquals(expectedE, list.toArray());
 	}
 
-	private int[] removeElements(final int[] data, final int... removedElements) {
-		final int[] result = new int[data.length - removedElements.length];
-		final List<Integer> blacklist = Arrays.stream(removedElements).boxed().collect(Collectors.toList());
+	private int[] removeElements(final int[] data, final int... removedIndices) {
+		final int[] result = new int[data.length - removedIndices.length];
+		final List<Integer> blacklist = Arrays.stream(removedIndices).boxed().collect(Collectors.toList());
 
 		int j = 0;
 		for (int i = 0; i < data.length; i++) {