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/*
* Copyright (C) 2010 Google Inc.
*
* 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 benchmarks.regression;
import java.nio.charset.Charset;
import com.google.caliper.Param;
import com.google.caliper.SimpleBenchmark;
public class CharsetBenchmark extends SimpleBenchmark {
@Param({ "1", "10", "100", "1000", "10000" })
private int length;
// canonical => canonical charset name
// built-in => guaranteed-present charset
// special-case => libcore treats this charset specially for performance
@Param({
"UTF-16", // canonical, built-in, non-special-case
"UTF-8", // canonical, built-in, special-case
"UTF8", // non-canonical, built-in, special-case
"ISO-8859-1", // canonical, built-in, special-case
"8859_1", // non-canonical, built-in, special-case
"ISO-8859-2", // canonical, non-built-in, non-special-case
"8859_2", // non-canonical, non-built-in, non-special-case
"US-ASCII", // canonical, built-in, special-case
"ASCII" // non-canonical, built-in, special-case
})
private String name;
public void time_new_String_BString(int reps) throws Exception {
byte[] bytes = makeBytes(makeString(length));
for (int i = 0; i < reps; ++i) {
new String(bytes, name);
}
}
public void time_new_String_BII(int reps) throws Exception {
byte[] bytes = makeBytes(makeString(length));
for (int i = 0; i < reps; ++i) {
new String(bytes, 0, bytes.length);
}
}
public void time_new_String_BIIString(int reps) throws Exception {
byte[] bytes = makeBytes(makeString(length));
for (int i = 0; i < reps; ++i) {
new String(bytes, 0, bytes.length, name);
}
}
public void time_String_getBytes(int reps) throws Exception {
String string = makeString(length);
for (int i = 0; i < reps; ++i) {
string.getBytes(name);
}
}
// FIXME: benchmark this pure-java implementation for US-ASCII and ISO-8859-1 too!
/**
* Translates the given characters to US-ASCII or ISO-8859-1 bytes, using the fact that
* Unicode code points between U+0000 and U+007f inclusive are identical to US-ASCII, while
* U+0000 to U+00ff inclusive are identical to ISO-8859-1.
*/
private static byte[] toDirectMappedBytes(char[] chars, int offset, int length, int maxValidChar) {
byte[] result = new byte[length];
int o = offset;
for (int i = 0; i < length; ++i) {
int ch = chars[o++];
result[i] = (byte) ((ch <= maxValidChar) ? ch : '?');
}
return result;
}
private static byte[] toUtf8Bytes(char[] chars, int offset, int length) {
UnsafeByteSequence result = new UnsafeByteSequence(length);
toUtf8Bytes(chars, offset, length, result);
return result.toByteArray();
}
private static void toUtf8Bytes(char[] chars, int offset, int length, UnsafeByteSequence out) {
final int end = offset + length;
for (int i = offset; i < end; ++i) {
int ch = chars[i];
if (ch < 0x80) {
// One byte.
out.write(ch);
} else if (ch < 0x800) {
// Two bytes.
out.write((ch >> 6) | 0xc0);
out.write((ch & 0x3f) | 0x80);
} else if (ch >= Character.MIN_SURROGATE && ch <= Character.MAX_SURROGATE) {
// A supplementary character.
char high = (char) ch;
char low = (i + 1 != end) ? chars[i + 1] : '\u0000';
if (!Character.isSurrogatePair(high, low)) {
out.write('?');
continue;
}
// Now we know we have a *valid* surrogate pair, we can consume the low surrogate.
++i;
ch = Character.toCodePoint(high, low);
// Four bytes.
out.write((ch >> 18) | 0xf0);
out.write(((ch >> 12) & 0x3f) | 0x80);
out.write(((ch >> 6) & 0x3f) | 0x80);
out.write((ch & 0x3f) | 0x80);
} else {
// Three bytes.
out.write((ch >> 12) | 0xe0);
out.write(((ch >> 6) & 0x3f) | 0x80);
out.write((ch & 0x3f) | 0x80);
}
}
}
private static String makeString(int length) {
StringBuilder result = new StringBuilder(length);
for (int i = 0; i < length; ++i) {
result.append('A' + (i % 26));
}
return result.toString();
}
private static byte[] makeBytes(String s) {
try {
return s.getBytes("US-ASCII");
} catch (Exception ex) {
throw new RuntimeException(ex);
}
}
}
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