LatinIME/java/src/com/android/inputmethod/latin/utils/ResizableIntArray.java
Keisuke Kuroyanagi e8754aba1c [AC7] Actually auto-commit.
Bug: 9059617
Change-Id: I7e5d89a9037b9181a0a6456c12043b4bfda8fe4b
2013-09-17 16:44:50 +09:00

155 lines
4.8 KiB
Java

/*
* Copyright (C) 2012 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 com.android.inputmethod.latin.utils;
import java.util.Arrays;
// TODO: This class is not thread-safe.
public final class ResizableIntArray {
private int[] mArray;
private int mLength;
public ResizableIntArray(final int capacity) {
reset(capacity);
}
public int get(final int index) {
if (index < mLength) {
return mArray[index];
}
throw new ArrayIndexOutOfBoundsException("length=" + mLength + "; index=" + index);
}
public void add(final int index, final int val) {
if (index < mLength) {
mArray[index] = val;
} else {
mLength = index;
add(val);
}
}
public void add(final int val) {
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) {
final int newCapacity = calculateCapacity(minimumCapacity);
if (newCapacity > 0) {
// TODO: Implement primitive array pool.
mArray = Arrays.copyOf(mArray, newCapacity);
}
}
public int getLength() {
return mLength;
}
public void setLength(final int newLength) {
ensureCapacity(newLength);
mLength = newLength;
}
public void reset(final int capacity) {
// TODO: Implement primitive array pool.
mArray = new int[capacity];
mLength = 0;
}
public int[] getPrimitiveArray() {
return mArray;
}
public void set(final ResizableIntArray ip) {
// TODO: Implement primitive array pool.
mArray = ip.mArray;
mLength = ip.mLength;
}
public void copy(final ResizableIntArray ip) {
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;
}
}
/**
* Shift to the left by elementCount, discarding elementCount pointers at the start.
* @param elementCount how many elements to shift.
*/
public void shift(final int elementCount) {
System.arraycopy(mArray, elementCount, mArray, 0, mLength - elementCount);
mLength -= elementCount;
}
@Override
public String toString() {
final StringBuilder sb = new StringBuilder();
for (int i = 0; i < mLength; i++) {
if (i != 0) {
sb.append(",");
}
sb.append(mArray[i]);
}
return "[" + sb + "]";
}
}