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1
8
9 package com.sleepycat.je.util;
10
11 import java.util.Random  ;
12 import java.util.zip.Checksum ;
13
14 import junit.framework.TestCase;
15
16 public class Adler32Test extends TestCase {
17
18 static private int N_ITERS = 1000;
19
20 public void testRandomAdler32ByteArray() {
21 Checksum javaChecksum = new java.util.zip.Adler32 ();
22 Checksum jeChecksum = new com.sleepycat.je.utilint.Adler32();
23 Checksum chunkingChecksum =
24 new com.sleepycat.je.utilint.Adler32.ChunkingAdler32(128);
25 Random rnd = new Random ();
26 for (int i = 0; i < N_ITERS; i++) {
27 int nBytes = rnd.nextInt(65535);
28 byte[] b = new byte[nBytes];
29 rnd.nextBytes(b);
30 javaChecksum.reset();
31 jeChecksum.reset();
32 chunkingChecksum.reset();
33 javaChecksum.update(b, 0, nBytes);
34 jeChecksum.update(b, 0, nBytes);
35 chunkingChecksum.update(b, 0, nBytes);
36 assertEquals(javaChecksum.getValue(), jeChecksum.getValue());
37 assertEquals(javaChecksum.getValue(), chunkingChecksum.getValue());
38 }
39 }
40
41 public void xtestRandomAdler32ByteArrayPerformance() {
42 Checksum javaChecksum = new java.util.zip.Adler32 ();
43 Checksum jeChecksum = new com.sleepycat.je.utilint.Adler32();
44 Random rnd = new Random ();
45 byte[][] baa = new byte[N_ITERS][];
46 int[] lengths = new int[N_ITERS];
47 long totalBytes = 0;
48 for (int i = 0; i < N_ITERS; i++) {
49 int nBytes = rnd.nextInt(65535);
50 byte[] b = new byte[nBytes];
51 baa[i] = b;
52 lengths[i] = nBytes;
53 totalBytes += nBytes;
54 rnd.nextBytes(b);
55 }
56 long jeChecksumTime =
57 measureChecksum(baa, lengths, jeChecksum, false);
58 long javaChecksumTime =
59 measureChecksum(baa, lengths, javaChecksum, false);
60 long jeChecksumTimeByteAtATime =
61 measureChecksum(baa, lengths, jeChecksum, true);
62 long javaChecksumTimeByteAtATime =
63 measureChecksum(baa, lengths, javaChecksum, true);
64 System.out.println(N_ITERS + " Iterations, " +
65 totalBytes + " bytes:\n " +
66 javaChecksumTime + " millis. for java\n" +
67 jeChecksumTime + " millis. for je\n" +
68 javaChecksumTimeByteAtATime +
69 " millis. for java byte at a time\n" +
70 jeChecksumTimeByteAtATime +
71 " millis. for je byte at a time");
72 }
73
74 private long measureChecksum(byte[][] baa,
75 int[] lengths,
76 Checksum cksum,
77 boolean byteAtATime) {
78 long startTime = System.currentTimeMillis();
79 for (int i = 0; i < N_ITERS; i++) {
80 byte[] b = baa[i];
81 int len = lengths[i];
82 cksum.reset();
83 if (byteAtATime) {
84 for (int j = 0; j < len; j++) {
85 cksum.update(b[j]);
86 }
87 } else {
88 cksum.update(b, 0, len);
89 }
90 }
91 long endTime = System.currentTimeMillis();
92 return (endTime - startTime);
93 }
94
95 public void testRandomAdler32SingleBytes() {
96 Checksum javaChecksum = new java.util.zip.Adler32 ();
97 Checksum jeChecksum = new com.sleepycat.je.utilint.Adler32();
98 Random rnd = new Random ();
99 for (int i = 0; i < N_ITERS; i++) {
100 int nBytes = rnd.nextInt(65535);
101 javaChecksum.reset();
102 jeChecksum.reset();
103 for (int j = 0; j < nBytes; j++) {
104 byte b = (byte) (rnd.nextInt(256) & 0xff);
105 javaChecksum.update(b);
106 jeChecksum.update(b);
107 }
108 assertEquals(javaChecksum.getValue(), jeChecksum.getValue());
109 }
110 }
111 }
112 |
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