Implement ResizableIntArray.fill
Change-Id: I570641bc2f32d016c247db6c065a138d8235ab8cmain
parent
19ac19e5fd
commit
7abdcf1ed3
|
@ -28,38 +28,49 @@ public class ResizableIntArray {
|
|||
}
|
||||
|
||||
public int get(final int index) {
|
||||
if (index < 0 || index >= mLength) {
|
||||
throw new ArrayIndexOutOfBoundsException("length=" + mLength + "; index=" + index);
|
||||
if (index < mLength) {
|
||||
return mArray[index];
|
||||
}
|
||||
return mArray[index];
|
||||
throw new ArrayIndexOutOfBoundsException("length=" + mLength + "; index=" + index);
|
||||
}
|
||||
|
||||
public void add(final int index, final int val) {
|
||||
if (mLength < index + 1) {
|
||||
if (index < mLength) {
|
||||
mArray[index] = val;
|
||||
} else {
|
||||
mLength = index;
|
||||
add(val);
|
||||
} else {
|
||||
mArray[index] = val;
|
||||
}
|
||||
}
|
||||
|
||||
public void add(final int val) {
|
||||
final int nextLength = mLength + 1;
|
||||
ensureCapacity(nextLength);
|
||||
mArray[mLength] = val;
|
||||
mLength = nextLength;
|
||||
final int currentLength = mLength;
|
||||
ensureCapacity(currentLength + 1);
|
||||
mArray[currentLength] = val;
|
||||
mLength = currentLength + 1;
|
||||
}
|
||||
|
||||
/**
|
||||
* Calculate the new capacity of {@code mArray}.
|
||||
* @param minimumCapacity the minimum capacity that the {@code mArray} should have.
|
||||
* @return the new capacity that the {@code mArray} should have. Returns zero when there is no
|
||||
* need to expand {@code mArray}.
|
||||
*/
|
||||
private int calculateCapacity(final int minimumCapacity) {
|
||||
final int currentCapcity = mArray.length;
|
||||
if (currentCapcity < minimumCapacity) {
|
||||
final int nextCapacity = currentCapcity * 2;
|
||||
// The following is the same as return Math.max(minimumCapacity, nextCapacity);
|
||||
return minimumCapacity > nextCapacity ? minimumCapacity : nextCapacity;
|
||||
}
|
||||
return 0;
|
||||
}
|
||||
|
||||
private void ensureCapacity(final int minimumCapacity) {
|
||||
if (mArray.length < minimumCapacity) {
|
||||
final int nextCapacity = mArray.length * 2;
|
||||
// The following is the same as newLength =
|
||||
// Math.max(minimumCapacity, nextCapacity);
|
||||
final int newLength = minimumCapacity > nextCapacity
|
||||
? minimumCapacity
|
||||
: nextCapacity;
|
||||
final int newCapacity = calculateCapacity(minimumCapacity);
|
||||
if (newCapacity > 0) {
|
||||
// TODO: Implement primitive array pool.
|
||||
mArray = Arrays.copyOf(mArray, newLength);
|
||||
mArray = Arrays.copyOf(mArray, newCapacity);
|
||||
}
|
||||
}
|
||||
|
||||
|
@ -89,17 +100,35 @@ public class ResizableIntArray {
|
|||
}
|
||||
|
||||
public void copy(final ResizableIntArray ip) {
|
||||
// TODO: Avoid useless coping of values.
|
||||
ensureCapacity(ip.mLength);
|
||||
final int newCapacity = calculateCapacity(ip.mLength);
|
||||
if (newCapacity > 0) {
|
||||
// TODO: Implement primitive array pool.
|
||||
mArray = new int[newCapacity];
|
||||
}
|
||||
System.arraycopy(ip.mArray, 0, mArray, 0, ip.mLength);
|
||||
mLength = ip.mLength;
|
||||
}
|
||||
|
||||
public void append(final ResizableIntArray src, final int startPos, final int length) {
|
||||
if (length == 0) {
|
||||
return;
|
||||
}
|
||||
final int currentLength = mLength;
|
||||
final int newLength = currentLength + length;
|
||||
ensureCapacity(newLength);
|
||||
System.arraycopy(src.mArray, startPos, mArray, currentLength, length);
|
||||
mLength = newLength;
|
||||
}
|
||||
|
||||
public void fill(final int value, final int startPos, final int length) {
|
||||
if (startPos < 0 || length < 0) {
|
||||
throw new IllegalArgumentException("startPos=" + startPos + "; length=" + length);
|
||||
}
|
||||
final int endPos = startPos + length;
|
||||
ensureCapacity(endPos);
|
||||
Arrays.fill(mArray, startPos, endPos, value);
|
||||
if (mLength < endPos) {
|
||||
mLength = endPos;
|
||||
}
|
||||
}
|
||||
}
|
||||
|
|
|
@ -37,8 +37,12 @@ public class ResizableIntArrayTests extends AndroidTestCase {
|
|||
for (int i = 0; i < limit; i++) {
|
||||
src.add(i);
|
||||
assertEquals("length after add " + i, i + 1, src.getLength());
|
||||
if (i == DEFAULT_CAPACITY) array2 = src.getPrimitiveArray();
|
||||
if (i == DEFAULT_CAPACITY * 2) array3 = src.getPrimitiveArray();
|
||||
if (i == DEFAULT_CAPACITY) {
|
||||
array2 = src.getPrimitiveArray();
|
||||
}
|
||||
if (i == DEFAULT_CAPACITY * 2) {
|
||||
array3 = src.getPrimitiveArray();
|
||||
}
|
||||
if (i < DEFAULT_CAPACITY) {
|
||||
assertSame("array after add " + i, array, src.getPrimitiveArray());
|
||||
} else if (i < DEFAULT_CAPACITY * 2) {
|
||||
|
@ -110,7 +114,9 @@ public class ResizableIntArrayTests extends AndroidTestCase {
|
|||
for (int i = 0; i < DEFAULT_CAPACITY; i++) {
|
||||
src.add(i);
|
||||
assertEquals("length after add " + i, i + 1, src.getLength());
|
||||
if (i == smallerLength) array3 = src.getPrimitiveArray();
|
||||
if (i == smallerLength) {
|
||||
array3 = src.getPrimitiveArray();
|
||||
}
|
||||
if (i < smallerLength) {
|
||||
assertSame("array after add " + i, array2, src.getPrimitiveArray());
|
||||
} else if (i < smallerLength * 2) {
|
||||
|
@ -133,11 +139,13 @@ public class ResizableIntArrayTests extends AndroidTestCase {
|
|||
assertEquals("length after larger setLength", largerLength, src.getLength());
|
||||
assertNotSame("array after larger setLength", array, array2);
|
||||
assertEquals("array length after larger setLength", largerLength, array2.length);
|
||||
for (int i = 0; i < DEFAULT_CAPACITY; i++) {
|
||||
assertEquals("value at " + i, i, src.get(i));
|
||||
}
|
||||
for (int i = DEFAULT_CAPACITY; i < largerLength; i++) {
|
||||
assertEquals("value at " + i, 0, src.get(i));
|
||||
for (int i = 0; i < largerLength; i++) {
|
||||
final int v = src.get(i);
|
||||
if (i < DEFAULT_CAPACITY) {
|
||||
assertEquals("value at " + i, i, v);
|
||||
} else {
|
||||
assertEquals("value at " + i, 0, v);
|
||||
}
|
||||
}
|
||||
|
||||
final int smallerLength = DEFAULT_CAPACITY / 2;
|
||||
|
@ -236,6 +244,79 @@ public class ResizableIntArrayTests extends AndroidTestCase {
|
|||
src.getPrimitiveArray(), 0, dst.getPrimitiveArray(), dstLen + srcLen, srcLen);
|
||||
}
|
||||
|
||||
public void testFill() {
|
||||
final int srcLen = DEFAULT_CAPACITY;
|
||||
final ResizableIntArray src = new ResizableIntArray(srcLen);
|
||||
for (int i = 0; i < srcLen; i++) {
|
||||
src.add(i);
|
||||
}
|
||||
final int[] array = src.getPrimitiveArray();
|
||||
|
||||
final int startPos = srcLen / 3;
|
||||
final int length = srcLen / 3;
|
||||
final int endPos = startPos + length;
|
||||
assertTrue(startPos >= 1);
|
||||
final int value = 123;
|
||||
try {
|
||||
src.fill(value, -1, length);
|
||||
fail("fill from -1 shouldn't succeed");
|
||||
} catch (IllegalArgumentException e) {
|
||||
// success
|
||||
}
|
||||
try {
|
||||
src.fill(value, startPos, -1);
|
||||
fail("fill negative length shouldn't succeed");
|
||||
} catch (IllegalArgumentException e) {
|
||||
// success
|
||||
}
|
||||
|
||||
src.fill(value, startPos, length);
|
||||
assertEquals("length after fill", srcLen, src.getLength());
|
||||
assertSame("array after fill", array, src.getPrimitiveArray());
|
||||
for (int i = 0; i < srcLen; i++) {
|
||||
final int v = src.get(i);
|
||||
if (i >= startPos && i < endPos) {
|
||||
assertEquals("new values after fill at " + i, value, v);
|
||||
} else {
|
||||
assertEquals("unmodified values after fill at " + i, i, v);
|
||||
}
|
||||
}
|
||||
|
||||
final int length2 = srcLen * 2 - startPos;
|
||||
final int largeEnd = startPos + length2;
|
||||
assertTrue(largeEnd > srcLen);
|
||||
final int value2 = 456;
|
||||
src.fill(value2, startPos, length2);
|
||||
assertEquals("length after large fill", largeEnd, src.getLength());
|
||||
assertNotSame("array after large fill", array, src.getPrimitiveArray());
|
||||
for (int i = 0; i < largeEnd; i++) {
|
||||
final int v = src.get(i);
|
||||
if (i >= startPos && i < largeEnd) {
|
||||
assertEquals("new values after large fill at " + i, value2, v);
|
||||
} else {
|
||||
assertEquals("unmodified values after large fill at " + i, i, v);
|
||||
}
|
||||
}
|
||||
|
||||
final int startPos2 = largeEnd + length2;
|
||||
final int endPos2 = startPos2 + length2;
|
||||
final int value3 = 789;
|
||||
src.fill(value3, startPos2, length2);
|
||||
assertEquals("length after disjoint fill", endPos2, src.getLength());
|
||||
for (int i = 0; i < endPos2; i++) {
|
||||
final int v = src.get(i);
|
||||
if (i >= startPos2 && i < endPos2) {
|
||||
assertEquals("new values after disjoint fill at " + i, value3, v);
|
||||
} else if (i >= startPos && i < largeEnd) {
|
||||
assertEquals("unmodified values after disjoint fill at " + i, value2, v);
|
||||
} else if (i < startPos) {
|
||||
assertEquals("unmodified values after disjoint fill at " + i, i, v);
|
||||
} else {
|
||||
assertEquals("gap values after disjoint fill at " + i, 0, v);
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
private static void assertArrayEquals(String message, int[] expecteds, int expectedPos,
|
||||
int[] actuals, int actualPos, int length) {
|
||||
if (expecteds == null && actuals == null) {
|
||||
|
|
Loading…
Reference in New Issue