1/*
2 * Copyright (C) 2007 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 *      http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17import java.util.Arrays;
18
19/**
20 * System.arraycopy cases
21 */
22public class Main {
23    public static void main(String args[]) {
24        testObjectCopy();
25        testOverlappingMoves();
26    }
27
28    public static void testObjectCopy() {
29        String[] stringArray = new String[8];
30        Object[] objectArray = new Object[8];
31
32        for (int i = 0; i < stringArray.length; i++)
33            stringArray[i] = new String(Integer.toString(i));
34
35        System.out.println("string -> object");
36        System.arraycopy(stringArray, 0, objectArray, 0, stringArray.length);
37        System.out.println("object -> string");
38        System.arraycopy(objectArray, 0, stringArray, 0, stringArray.length);
39        System.out.println("object -> string (modified)");
40        objectArray[4] = new ImplA();
41        try {
42            System.arraycopy(objectArray, 0, stringArray, 0,stringArray.length);
43        }
44        catch (ArrayStoreException ase) {
45            System.out.println("caught ArrayStoreException (expected)");
46        }
47    }
48
49    static final int ARRAY_SIZE = 8;
50
51    static void initByteArray(byte[] array) {
52        for (int i = 0; i < ARRAY_SIZE; i++) {
53            array[i] = (byte) i;
54        }
55    }
56    static void initShortArray(short[] array) {
57        for (int i = 0; i < ARRAY_SIZE; i++) {
58            array[i] = (short) i;
59        }
60    }
61    static void initIntArray(int[] array) {
62        for (int i = 0; i < ARRAY_SIZE; i++) {
63            array[i] = (int) i;
64        }
65    }
66    static void initLongArray(long[] array) {
67        for (int i = 0; i < ARRAY_SIZE; i++) {
68            array[i] = (long) i;
69        }
70    }
71
72    /*
73     * Perform an array copy operation on primitive arrays with different
74     * element widths.
75     */
76    static void makeCopies(int srcPos, int dstPos, int length) {
77        byte[] byteArray = new byte[ARRAY_SIZE];
78        short[] shortArray = new short[ARRAY_SIZE];
79        int[] intArray = new int[ARRAY_SIZE];
80        long[] longArray = new long[ARRAY_SIZE];
81
82        initByteArray(byteArray);
83        initShortArray(shortArray);
84        initIntArray(intArray);
85        initLongArray(longArray);
86
87        System.arraycopy(byteArray, srcPos, byteArray, dstPos, length);
88        System.arraycopy(shortArray, srcPos, shortArray, dstPos, length);
89        System.arraycopy(intArray, srcPos, intArray, dstPos, length);
90        System.arraycopy(longArray, srcPos, longArray, dstPos, length);
91
92        for (int i = 0; i < ARRAY_SIZE; i++) {
93            if (intArray[i] != byteArray[i]) {
94                System.out.println("mismatch int vs byte at " + i + " : " +
95                    Arrays.toString(byteArray));
96                break;
97            } else if (intArray[i] != shortArray[i]) {
98                System.out.println("mismatch int vs short at " + i + " : " +
99                    Arrays.toString(shortArray));
100                break;
101            } else if (intArray[i] != longArray[i]) {
102                System.out.println("mismatch int vs long at " + i + " : " +
103                    Arrays.toString(longArray));
104                break;
105            }
106        }
107
108        System.out.println("copy: " + srcPos + "," + dstPos + "," + length +
109            ": " + Arrays.toString(intArray));
110    }
111
112    public static void testOverlappingMoves() {
113        /* do nothing */
114        makeCopies(0, 0, 0);
115
116        /* do more nothing */
117        makeCopies(0, 0, ARRAY_SIZE);
118
119        /* copy forward, even alignment */
120        makeCopies(0, 2, 4);
121
122        /* copy backward, even alignment */
123        makeCopies(2, 0, 4);
124
125        /* copy forward, odd alignment */
126        makeCopies(1, 3, 4);
127
128        /* copy backward, odd alignment */
129        makeCopies(3, 1, 4);
130
131        /* copy backward, odd length */
132        makeCopies(3, 1, 5);
133
134        /* copy forward, odd length */
135        makeCopies(1, 3, 5);
136
137        /* copy forward, mixed alignment */
138        makeCopies(0, 3, 5);
139
140        /* copy backward, mixed alignment */
141        makeCopies(3, 0, 5);
142
143        /* copy forward, mixed alignment, trivial length */
144        makeCopies(0, 5, 1);
145    }
146}
147