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Android example source code file (ArrayUtils.java)
The ArrayUtils.java Android example source code/* * Copyright (C) 2006 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.internal.util; import java.lang.reflect.Array; import java.util.Collection; // XXX these should be changed to reflect the actual memory allocator we use. // it looks like right now objects want to be powers of 2 minus 8 // and the array size eats another 4 bytes /** * ArrayUtils contains some methods that you can call to find out * the most efficient increments by which to grow arrays. */ public class ArrayUtils { private static Object[] EMPTY = new Object[0]; private static final int CACHE_SIZE = 73; private static Object[] sCache = new Object[CACHE_SIZE]; private ArrayUtils() { /* cannot be instantiated */ } public static int idealByteArraySize(int need) { for (int i = 4; i < 32; i++) if (need <= (1 << i) - 12) return (1 << i) - 12; return need; } public static int idealBooleanArraySize(int need) { return idealByteArraySize(need); } public static int idealShortArraySize(int need) { return idealByteArraySize(need * 2) / 2; } public static int idealCharArraySize(int need) { return idealByteArraySize(need * 2) / 2; } public static int idealIntArraySize(int need) { return idealByteArraySize(need * 4) / 4; } public static int idealFloatArraySize(int need) { return idealByteArraySize(need * 4) / 4; } public static int idealObjectArraySize(int need) { return idealByteArraySize(need * 4) / 4; } public static int idealLongArraySize(int need) { return idealByteArraySize(need * 8) / 8; } /** * Checks if the beginnings of two byte arrays are equal. * * @param array1 the first byte array * @param array2 the second byte array * @param length the number of bytes to check * @return true if they're equal, false otherwise */ public static boolean equals(byte[] array1, byte[] array2, int length) { if (array1 == array2) { return true; } if (array1 == null || array2 == null || array1.length < length || array2.length < length) { return false; } for (int i = 0; i < length; i++) { if (array1[i] != array2[i]) { return false; } } return true; } /** * Returns an empty array of the specified type. The intent is that * it will return the same empty array every time to avoid reallocation, * although this is not guaranteed. */ public static <T> T[] emptyArray(Class Other Android examples (source code examples)Here is a short list of links related to this Android ArrayUtils.java source code file: |
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