/*
* Copyright (C) 2017 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package android.text;
import android.annotation.IntRange;
import android.annotation.NonNull;
import com.android.internal.util.ArrayUtils;
import libcore.util.EmptyArray;
/**
* Implements a growing array of int primitives.
*
* These arrays are NOT thread safe.
*
* @hide
*/
public final class AutoGrowArray {
private static final int MIN_CAPACITY_INCREMENT = 12;
private static final int MAX_CAPACITY_TO_BE_KEPT = 10000;
/**
* Returns next capacity size.
*
* The returned capacity is larger than requested capacity.
*/
private static int computeNewCapacity(int currentSize, int requested) {
final int targetCapacity = currentSize + (currentSize < (MIN_CAPACITY_INCREMENT / 2)
? MIN_CAPACITY_INCREMENT : currentSize >> 1);
return targetCapacity > requested ? targetCapacity : requested;
}
/**
* An auto growing byte array.
*/
public static class ByteArray {
private @NonNull byte[] mValues;
private @IntRange(from = 0) int mSize;
/**
* Creates an empty ByteArray with the default initial capacity.
*/
public ByteArray() {
this(10);
}
/**
* Creates an empty ByteArray with the specified initial capacity.
*/
public ByteArray(@IntRange(from = 0) int initialCapacity) {
if (initialCapacity == 0) {
mValues = EmptyArray.BYTE;
} else {
mValues = ArrayUtils.newUnpaddedByteArray(initialCapacity);
}
mSize = 0;
}
/**
* Changes the size of this ByteArray. If this ByteArray is shrinked, the backing array
* capacity is unchanged.
*/
public void resize(@IntRange(from = 0) int newSize) {
if (newSize > mValues.length) {
ensureCapacity(newSize - mSize);
}
mSize = newSize;
}
/**
* Appends the specified value to the end of this array.
*/
public void append(byte value) {
ensureCapacity(1);
mValues[mSize++] = value;
}
/**
* Ensures capacity to append at least <code>count</code> values.
*/
private void ensureCapacity(@IntRange int count) {
final int requestedSize = mSize + count;
if (requestedSize >= mValues.length) {
final int newCapacity = computeNewCapacity(mSize, requestedSize);
final byte[] newValues = ArrayUtils.newUnpaddedByteArray(newCapacity);
System.arraycopy(mValues, 0, newValues, 0, mSize);
mValues = newValues;
}
}
/**
* Removes all values from this array.
*/
public void clear() {
mSize = 0;
}
/**
* Removes all values from this array and release the internal array object if it is too
* large.
*/
public void clearWithReleasingLargeArray() {
clear();
if (mValues.length > MAX_CAPACITY_TO_BE_KEPT) {
mValues = EmptyArray.BYTE;
}
}
/**
* Returns the value at the specified position in this array.
*/
public byte get(@IntRange(from = 0) int index) {
return mValues[index];
}
/**
* Sets the value at the specified position in this array.
*/
public void set(@IntRange(from = 0) int index, byte value) {
mValues[index] = value;
}
/**
* Returns the number of values in this array.
*/
public @IntRange(from = 0) int size() {
return mSize;
}
/**
* Returns internal raw array.
*
* Note that this array may have larger size than you requested.
* Use size() instead for getting the actual array size.
*/
public @NonNull byte[] getRawArray() {
return mValues;
}
}
/**
* An auto growing int array.
*/
public static class IntArray {
private @NonNull int[] mValues;
private @IntRange(from = 0) int mSize;
/**
* Creates an empty IntArray with the default initial capacity.
*/
public IntArray() {
this(10);
}
/**
* Creates an empty IntArray with the specified initial capacity.
*/
public IntArray(@IntRange(from = 0) int initialCapacity) {
if (initialCapacity == 0) {
mValues = EmptyArray.INT;
} else {
mValues = ArrayUtils.newUnpaddedIntArray(initialCapacity);
}
mSize = 0;
}
/**
* Changes the size of this IntArray. If this IntArray is shrinked, the backing array
* capacity is unchanged.
*/
public void resize(@IntRange(from = 0) int newSize) {
if (newSize > mValues.length) {
ensureCapacity(newSize - mSize);
}
mSize = newSize;
}
/**
* Appends the specified value to the end of this array.
*/
public void append(int value) {
ensureCapacity(1);
mValues[mSize++] = value;
}
/**
* Ensures capacity to append at least <code>count</code> values.
*/
private void ensureCapacity(@IntRange(from = 0) int count) {
final int requestedSize = mSize + count;
if (requestedSize >= mValues.length) {
final int newCapacity = computeNewCapacity(mSize, requestedSize);
final int[] newValues = ArrayUtils.newUnpaddedIntArray(newCapacity);
System.arraycopy(mValues, 0, newValues, 0, mSize);
mValues = newValues;
}
}
/**
* Removes all values from this array.
*/
public void clear() {
mSize = 0;
}
/**
* Removes all values from this array and release the internal array object if it is too
* large.
*/
public void clearWithReleasingLargeArray() {
clear();
if (mValues.length > MAX_CAPACITY_TO_BE_KEPT) {
mValues = EmptyArray.INT;
}
}
/**
* Returns the value at the specified position in this array.
*/
public int get(@IntRange(from = 0) int index) {
return mValues[index];
}
/**
* Sets the value at the specified position in this array.
*/
public void set(@IntRange(from = 0) int index, int value) {
mValues[index] = value;
}
/**
* Returns the number of values in this array.
*/
public @IntRange(from = 0) int size() {
return mSize;
}
/**
* Returns internal raw array.
*
* Note that this array may have larger size than you requested.
* Use size() instead for getting the actual array size.
*/
public @NonNull int[] getRawArray() {
return mValues;
}
}
/**
* An auto growing float array.
*/
public static class FloatArray {
private @NonNull float[] mValues;
private @IntRange(from = 0) int mSize;
/**
* Creates an empty FloatArray with the default initial capacity.
*/
public FloatArray() {
this(10);
}
/**
* Creates an empty FloatArray with the specified initial capacity.
*/
public FloatArray(@IntRange(from = 0) int initialCapacity) {
if (initialCapacity == 0) {
mValues = EmptyArray.FLOAT;
} else {
mValues = ArrayUtils.newUnpaddedFloatArray(initialCapacity);
}
mSize = 0;
}
/**
* Changes the size of this FloatArray. If this FloatArray is shrinked, the backing array
* capacity is unchanged.
*/
public void resize(@IntRange(from = 0) int newSize) {
if (newSize > mValues.length) {
ensureCapacity(newSize - mSize);
}
mSize = newSize;
}
/**
* Appends the specified value to the end of this array.
*/
public void append(float value) {
ensureCapacity(1);
mValues[mSize++] = value;
}
/**
* Ensures capacity to append at least <code>count</code> values.
*/
private void ensureCapacity(int count) {
final int requestedSize = mSize + count;
if (requestedSize >= mValues.length) {
final int newCapacity = computeNewCapacity(mSize, requestedSize);
final float[] newValues = ArrayUtils.newUnpaddedFloatArray(newCapacity);
System.arraycopy(mValues, 0, newValues, 0, mSize);
mValues = newValues;
}
}
/**
* Removes all values from this array.
*/
public void clear() {
mSize = 0;
}
/**
* Removes all values from this array and release the internal array object if it is too
* large.
*/
public void clearWithReleasingLargeArray() {
clear();
if (mValues.length > MAX_CAPACITY_TO_BE_KEPT) {
mValues = EmptyArray.FLOAT;
}
}
/**
* Returns the value at the specified position in this array.
*/
public float get(@IntRange(from = 0) int index) {
return mValues[index];
}
/**
* Sets the value at the specified position in this array.
*/
public void set(@IntRange(from = 0) int index, float value) {
mValues[index] = value;
}
/**
* Returns the number of values in this array.
*/
public @IntRange(from = 0) int size() {
return mSize;
}
/**
* Returns internal raw array.
*
* Note that this array may have larger size than you requested.
* Use size() instead for getting the actual array size.
*/
public @NonNull float[] getRawArray() {
return mValues;
}
}
}