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A library jar that provides APIs for Applications written for the Google Android Platform.
/*
* Copyright (C) 2010 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 java.lang;
import android.icu.text.Transliterator;
import java.util.Locale;
import libcore.icu.ICU;
/**
* Performs case operations as described by http://unicode.org/reports/tr21/tr21-5.html.
*/
class CaseMapper {
private static final char[] upperValues = "SS\u0000\u02bcN\u0000J\u030c\u0000\u0399\u0308\u0301\u03a5\u0308\u0301\u0535\u0552\u0000H\u0331\u0000T\u0308\u0000W\u030a\u0000Y\u030a\u0000A\u02be\u0000\u03a5\u0313\u0000\u03a5\u0313\u0300\u03a5\u0313\u0301\u03a5\u0313\u0342\u1f08\u0399\u0000\u1f09\u0399\u0000\u1f0a\u0399\u0000\u1f0b\u0399\u0000\u1f0c\u0399\u0000\u1f0d\u0399\u0000\u1f0e\u0399\u0000\u1f0f\u0399\u0000\u1f08\u0399\u0000\u1f09\u0399\u0000\u1f0a\u0399\u0000\u1f0b\u0399\u0000\u1f0c\u0399\u0000\u1f0d\u0399\u0000\u1f0e\u0399\u0000\u1f0f\u0399\u0000\u1f28\u0399\u0000\u1f29\u0399\u0000\u1f2a\u0399\u0000\u1f2b\u0399\u0000\u1f2c\u0399\u0000\u1f2d\u0399\u0000\u1f2e\u0399\u0000\u1f2f\u0399\u0000\u1f28\u0399\u0000\u1f29\u0399\u0000\u1f2a\u0399\u0000\u1f2b\u0399\u0000\u1f2c\u0399\u0000\u1f2d\u0399\u0000\u1f2e\u0399\u0000\u1f2f\u0399\u0000\u1f68\u0399\u0000\u1f69\u0399\u0000\u1f6a\u0399\u0000\u1f6b\u0399\u0000\u1f6c\u0399\u0000\u1f6d\u0399\u0000\u1f6e\u0399\u0000\u1f6f\u0399\u0000\u1f68\u0399\u0000\u1f69\u0399\u0000\u1f6a\u0399\u0000\u1f6b\u0399\u0000\u1f6c\u0399\u0000\u1f6d\u0399\u0000\u1f6e\u0399\u0000\u1f6f\u0399\u0000\u1fba\u0399\u0000\u0391\u0399\u0000\u0386\u0399\u0000\u0391\u0342\u0000\u0391\u0342\u0399\u0391\u0399\u0000\u1fca\u0399\u0000\u0397\u0399\u0000\u0389\u0399\u0000\u0397\u0342\u0000\u0397\u0342\u0399\u0397\u0399\u0000\u0399\u0308\u0300\u0399\u0308\u0301\u0399\u0342\u0000\u0399\u0308\u0342\u03a5\u0308\u0300\u03a5\u0308\u0301\u03a1\u0313\u0000\u03a5\u0342\u0000\u03a5\u0308\u0342\u1ffa\u0399\u0000\u03a9\u0399\u0000\u038f\u0399\u0000\u03a9\u0342\u0000\u03a9\u0342\u0399\u03a9\u0399\u0000FF\u0000FI\u0000FL\u0000FFIFFLST\u0000ST\u0000\u0544\u0546\u0000\u0544\u0535\u0000\u0544\u053b\u0000\u054e\u0546\u0000\u0544\u053d\u0000".toCharArray();
private static final char[] upperValues2 = "\u000b\u0000\f\u0000\r\u0000\u000e\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u000f\u0010\u0011\u0012\u0013\u0014\u0015\u0016\u0017\u0018\u0019\u001a\u001b\u001c\u001d\u001e\u001f !\"#$%&'()*+,-./0123456789:;<=>\u0000\u0000?@A\u0000BC\u0000\u0000\u0000\u0000D\u0000\u0000\u0000\u0000\u0000EFG\u0000HI\u0000\u0000\u0000\u0000J\u0000\u0000\u0000\u0000\u0000KL\u0000\u0000MN\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000OPQ\u0000RS\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000TUV\u0000WX\u0000\u0000\u0000\u0000Y".toCharArray();
private static final char LATIN_CAPITAL_I_WITH_DOT = '\u0130';
private static final char GREEK_CAPITAL_SIGMA = '\u03a3';
private static final char GREEK_SMALL_FINAL_SIGMA = '\u03c2';
/**
* Our current GC makes short-lived objects more expensive than we'd like. When that's fixed,
* this class should be changed so that you instantiate it with the String and its value,
* and count fields.
*/
private CaseMapper() {
}
/**
* Implements String.toLowerCase. The original String instance is returned if nothing changes.
*/
public static String toLowerCase(Locale locale, String s) {
// Punt hard cases to ICU4C.
// Note that Greek isn't a particularly hard case for toLowerCase, only toUpperCase.
String languageCode = locale.getLanguage();
if (languageCode.equals("tr") || languageCode.equals("az") || languageCode.equals("lt")) {
return ICU.toLowerCase(s, locale);
}
char[] newValue = null;
for (int i = 0, end = s.length(); i < end; ++i) {
char ch = s.charAt(i);
char newCh;
if (ch == LATIN_CAPITAL_I_WITH_DOT || Character.isHighSurrogate(ch)) {
// Punt these hard cases.
return ICU.toLowerCase(s, locale);
} else if (ch == GREEK_CAPITAL_SIGMA && isFinalSigma(s, i)) {
newCh = GREEK_SMALL_FINAL_SIGMA;
} else {
newCh = Character.toLowerCase(ch);
}
if (ch != newCh) {
if (newValue == null) {
newValue = new char[end];
s.getCharsNoCheck(0, end, newValue, 0);
}
newValue[i] = newCh;
}
}
return newValue != null ? new String(newValue) : s;
}
/**
* True if 'index' is preceded by a sequence consisting of a cased letter and a case-ignorable
* sequence, and 'index' is not followed by a sequence consisting of an ignorable sequence and
* then a cased letter.
*/
private static boolean isFinalSigma(String s, int index) {
// TODO: we don't skip case-ignorable sequences like we should.
// TODO: we should add a more direct way to test for a cased letter.
if (index <= 0) {
return false;
}
char previous = s.charAt(index - 1);
if (!(Character.isLowerCase(previous) || Character.isUpperCase(previous) || Character.isTitleCase(previous))) {
return false;
}
if (index + 1 >= s.length()) {
return true;
}
char next = s.charAt(index + 1);
if (Character.isLowerCase(next) || Character.isUpperCase(next) || Character.isTitleCase(next)) {
return false;
}
return true;
}
/**
* Return the index of the specified character into the upperValues table.
* The upperValues table contains three entries at each position. These
* three characters are the upper case conversion. If only two characters
* are used, the third character in the table is \u0000.
* @return the index into the upperValues table, or -1
*/
private static int upperIndex(int ch) {
int index = -1;
if (ch >= 0xdf) {
if (ch <= 0x587) {
switch (ch) {
case 0xdf: return 0;
case 0x149: return 1;
case 0x1f0: return 2;
case 0x390: return 3;
case 0x3b0: return 4;
case 0x587: return 5;
}
} else if (ch >= 0x1e96) {
if (ch <= 0x1e9a) {
index = 6 + ch - 0x1e96;
} else if (ch >= 0x1f50 && ch <= 0x1ffc) {
index = upperValues2[ch - 0x1f50];
if (index == 0) {
index = -1;
}
} else if (ch >= 0xfb00) {
if (ch <= 0xfb06) {
index = 90 + ch - 0xfb00;
} else if (ch >= 0xfb13 && ch <= 0xfb17) {
index = 97 + ch - 0xfb13;
}
}
}
}
return index;
}
private static final ThreadLocal EL_UPPER = new ThreadLocal() {
@Override protected Transliterator initialValue() {
return Transliterator.getInstance("el-Upper");
}
};
public static String toUpperCase(Locale locale, String s, int count) {
String languageCode = locale.getLanguage();
if (languageCode.equals("tr") || languageCode.equals("az") || languageCode.equals("lt")) {
return ICU.toUpperCase(s, locale);
}
if (languageCode.equals("el")) {
return EL_UPPER.get().transliterate(s);
}
char[] output = null;
int i = 0;
for (int o = 0; o < count; o++) {
char ch = s.charAt(o);
if (Character.isHighSurrogate(ch)) {
return ICU.toUpperCase(s, locale);
}
int index = upperIndex(ch);
if (index == -1) {
if (output != null && i >= output.length) {
char[] newoutput = new char[output.length + (count / 6) + 2];
System.arraycopy(output, 0, newoutput, 0, output.length);
output = newoutput;
}
char upch = Character.toUpperCase(ch);
if (output != null) {
output[i++] = upch;
} else if (ch != upch) {
output = new char[count];
i = o;
s.getCharsNoCheck(0, i, output, 0);
output[i++] = upch;
}
} else {
int target = index * 3;
char val3 = upperValues[target + 2];
if (output == null) {
output = new char[count + (count / 6) + 2];
i = o;
s.getCharsNoCheck(0, i, output, 0);
} else if (i + (val3 == 0 ? 1 : 2) >= output.length) {
char[] newoutput = new char[output.length + (count / 6) + 3];
System.arraycopy(output, 0, newoutput, 0, output.length);
output = newoutput;
}
char val = upperValues[target];
output[i++] = val;
val = upperValues[target + 1];
output[i++] = val;
if (val3 != 0) {
output[i++] = val3;
}
}
}
if (output == null) {
return s;
}
return output.length == i || output.length - i < 8 ? new String(0, i, output) : new String(output, 0, i);
}
}