/** Create a new ArrayMap with a given initial capacity. */
public ArrayMap(int capacity) {
if (capacity == 0) {
mHashes = ContainerHelpers.EMPTY_INTS;
mArray = ContainerHelpers.EMPTY_OBJECTS;
} else {
allocArrays(capacity);
}
mSize = 0;
}
/** Ensure the array map can hold at least <var>minimumCapacity</var> items. */
public void ensureCapacity(int minimumCapacity) {
if (mHashes.length < minimumCapacity) {
final int[] ohashes = mHashes;
final Object[] oarray = mArray;
allocArrays(minimumCapacity);
if (mSize > 0) {
System.arraycopy(ohashes, 0, mHashes, 0, mSize);
System.arraycopy(oarray, 0, mArray, 0, mSize << 1);
}
freeArrays(ohashes, oarray, mSize);
}
}
/**
* Add a new value to the array map.
*
* @param key The key under which to store the value. <b>Must not be null.</b> If this key already
* exists in the array, its value will be replaced.
* @param value The value to store for the given key.
* @return Returns the old value that was stored for the given key, or null if there was no such
* key.
*/
@Override
public V put(K key, V value) {
final int hash;
int index;
if (key == null) {
hash = 0;
index = indexOfNull();
} else {
hash = key.hashCode();
index = indexOf(key, hash);
}
if (index >= 0) {
index = (index << 1) + 1;
final V old = (V) mArray[index];
mArray[index] = value;
return old;
}
index = ~index;
if (mSize >= mHashes.length) {
final int n =
mSize >= (BASE_SIZE * 2)
? (mSize + (mSize >> 1))
: (mSize >= BASE_SIZE ? (BASE_SIZE * 2) : BASE_SIZE);
if (DEBUG) Log.d(TAG, "put: grow from " + mHashes.length + " to " + n);
final int[] ohashes = mHashes;
final Object[] oarray = mArray;
allocArrays(n);
if (mHashes.length > 0) {
if (DEBUG) Log.d(TAG, "put: copy 0-" + mSize + " to 0");
System.arraycopy(ohashes, 0, mHashes, 0, ohashes.length);
System.arraycopy(oarray, 0, mArray, 0, oarray.length);
}
freeArrays(ohashes, oarray, mSize);
}
if (index < mSize) {
if (DEBUG) Log.d(TAG, "put: move " + index + "-" + (mSize - index) + " to " + (index + 1));
System.arraycopy(mHashes, index, mHashes, index + 1, mSize - index);
System.arraycopy(mArray, index << 1, mArray, (index + 1) << 1, (mSize - index) << 1);
}
mHashes[index] = hash;
mArray[index << 1] = key;
mArray[(index << 1) + 1] = value;
mSize++;
return null;
}
/**
* Remove the key/value mapping at the given index.
*
* @param index The desired index, must be between 0 and {@link #size()}-1.
* @return Returns the value that was stored at this index.
*/
public V removeAt(int index) {
final Object old = mArray[(index << 1) + 1];
if (mSize <= 1) {
// Now empty.
if (DEBUG) Log.d(TAG, "remove: shrink from " + mHashes.length + " to 0");
freeArrays(mHashes, mArray, mSize);
mHashes = ContainerHelpers.EMPTY_INTS;
mArray = ContainerHelpers.EMPTY_OBJECTS;
mSize = 0;
} else {
if (mHashes.length > (BASE_SIZE * 2) && mSize < mHashes.length / 3) {
// Shrunk enough to reduce size of arrays. We don't allow it to
// shrink smaller than (BASE_SIZE*2) to avoid flapping between
// that and BASE_SIZE.
final int n = mSize > (BASE_SIZE * 2) ? (mSize + (mSize >> 1)) : (BASE_SIZE * 2);
if (DEBUG) Log.d(TAG, "remove: shrink from " + mHashes.length + " to " + n);
final int[] ohashes = mHashes;
final Object[] oarray = mArray;
allocArrays(n);
mSize--;
if (index > 0) {
if (DEBUG) Log.d(TAG, "remove: copy from 0-" + index + " to 0");
System.arraycopy(ohashes, 0, mHashes, 0, index);
System.arraycopy(oarray, 0, mArray, 0, index << 1);
}
if (index < mSize) {
if (DEBUG) Log.d(TAG, "remove: copy from " + (index + 1) + "-" + mSize + " to " + index);
System.arraycopy(ohashes, index + 1, mHashes, index, mSize - index);
System.arraycopy(oarray, (index + 1) << 1, mArray, index << 1, (mSize - index) << 1);
}
} else {
mSize--;
if (index < mSize) {
if (DEBUG) Log.d(TAG, "remove: move " + (index + 1) + "-" + mSize + " to " + index);
System.arraycopy(mHashes, index + 1, mHashes, index, mSize - index);
System.arraycopy(mArray, (index + 1) << 1, mArray, index << 1, (mSize - index) << 1);
}
mArray[mSize << 1] = null;
mArray[(mSize << 1) + 1] = null;
}
}
return (V) old;
}