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/*
* Copyright (C) 2007 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.
*/
import java.util.Arrays;
/**
* System.arraycopy cases
*/
public class Main {
public static void main(String args[]) {
testObjectCopy();
testOverlappingMoves();
}
public static void testObjectCopy() {
String[] stringArray = new String[8];
Object[] objectArray = new Object[8];
for (int i = 0; i < stringArray.length; i++)
stringArray[i] = new String(Integer.toString(i));
System.out.println("string -> object");
System.arraycopy(stringArray, 0, objectArray, 0, stringArray.length);
System.out.println("object -> string");
System.arraycopy(objectArray, 0, stringArray, 0, stringArray.length);
System.out.println("object -> string (modified)");
objectArray[4] = new ImplA();
try {
System.arraycopy(objectArray, 0, stringArray, 0,stringArray.length);
}
catch (ArrayStoreException ase) {
System.out.println("caught ArrayStoreException (expected)");
}
}
static final int ARRAY_SIZE = 8;
static void initByteArray(byte[] array) {
for (int i = 0; i < ARRAY_SIZE; i++) {
array[i] = (byte) i;
}
}
static void initShortArray(short[] array) {
for (int i = 0; i < ARRAY_SIZE; i++) {
array[i] = (short) i;
}
}
static void initIntArray(int[] array) {
for (int i = 0; i < ARRAY_SIZE; i++) {
array[i] = (int) i;
}
}
static void initLongArray(long[] array) {
for (int i = 0; i < ARRAY_SIZE; i++) {
array[i] = (long) i;
}
}
/*
* Perform an array copy operation on primitive arrays with different
* element widths.
*/
static void makeCopies(int srcPos, int dstPos, int length) {
byte[] byteArray = new byte[ARRAY_SIZE];
short[] shortArray = new short[ARRAY_SIZE];
int[] intArray = new int[ARRAY_SIZE];
long[] longArray = new long[ARRAY_SIZE];
initByteArray(byteArray);
initShortArray(shortArray);
initIntArray(intArray);
initLongArray(longArray);
System.arraycopy(byteArray, srcPos, byteArray, dstPos, length);
System.arraycopy(shortArray, srcPos, shortArray, dstPos, length);
System.arraycopy(intArray, srcPos, intArray, dstPos, length);
System.arraycopy(longArray, srcPos, longArray, dstPos, length);
for (int i = 0; i < ARRAY_SIZE; i++) {
if (intArray[i] != byteArray[i]) {
System.out.println("mismatch int vs byte at " + i + " : " +
Arrays.toString(byteArray));
break;
} else if (intArray[i] != shortArray[i]) {
System.out.println("mismatch int vs short at " + i + " : " +
Arrays.toString(shortArray));
break;
} else if (intArray[i] != longArray[i]) {
System.out.println("mismatch int vs long at " + i + " : " +
Arrays.toString(longArray));
break;
}
}
System.out.println("copy: " + srcPos + "," + dstPos + "," + length +
": " + Arrays.toString(intArray));
}
public static void testOverlappingMoves() {
/* do nothing */
makeCopies(0, 0, 0);
/* do more nothing */
makeCopies(0, 0, ARRAY_SIZE);
/* copy forward, even alignment */
makeCopies(0, 2, 4);
/* copy backward, even alignment */
makeCopies(2, 0, 4);
/* copy forward, odd alignment */
makeCopies(1, 3, 4);
/* copy backward, odd alignment */
makeCopies(3, 1, 4);
/* copy backward, odd length */
makeCopies(3, 1, 5);
/* copy forward, odd length */
makeCopies(1, 3, 5);
/* copy forward, mixed alignment */
makeCopies(0, 3, 5);
/* copy backward, mixed alignment */
makeCopies(3, 0, 5);
/* copy forward, mixed alignment, trivial length */
makeCopies(0, 5, 1);
}
}
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