diff options
author | Victor Chang <vichang@google.com> | 2021-04-30 13:12:18 +0100 |
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committer | vichang <vichang@google.com> | 2021-04-30 12:20:37 +0000 |
commit | e7e36af1b0d1478c92b3dde5f7440967c1ad829a (patch) | |
tree | 2d9e031a5959c4be0af88b0596118802b59d1862 /android_icu4j | |
parent | 92c98b5ce08b660f9fbff5b95d0567f15747f0e9 (diff) | |
download | icu-e7e36af1b0d1478c92b3dde5f7440967c1ad829a.tar.gz |
Cherry-pick: ICU-21567 Avoid using regex in ULocale.getName()
Improve memory usage and no behavior change is expected
Bug: 182125668
Test: treehugger
Change-Id: I45094af09d20a01409e64650fe0825f9573387b5
Diffstat (limited to 'android_icu4j')
-rw-r--r-- | android_icu4j/src/main/java/android/icu/util/ULocale.java | 35 |
1 files changed, 31 insertions, 4 deletions
diff --git a/android_icu4j/src/main/java/android/icu/util/ULocale.java b/android_icu4j/src/main/java/android/icu/util/ULocale.java index 1339cb686..466b01a8b 100644 --- a/android_icu4j/src/main/java/android/icu/util/ULocale.java +++ b/android_icu4j/src/main/java/android/icu/util/ULocale.java @@ -29,7 +29,6 @@ import java.util.Objects; import java.util.Set; import java.util.TreeMap; import java.util.TreeSet; -import java.util.regex.Pattern; import android.icu.impl.CacheBase; import android.icu.impl.ICUData; @@ -106,8 +105,6 @@ public final class ULocale implements Serializable, Comparable<ULocale> { // using serialver from jdk1.4.2_05 private static final long serialVersionUID = 3715177670352309217L; - private static final Pattern UND_PATTERN = Pattern.compile("^und(?=$|[_-])", Pattern.CASE_INSENSITIVE); - private static CacheBase<String, String, Void> nameCache = new SoftCache<String, String, Void>() { @Override protected String createInstance(String tmpLocaleID, Void unused) { @@ -1064,12 +1061,42 @@ public final class ULocale implements Serializable, Comparable<ULocale> { } else if ("root".equalsIgnoreCase(localeID)) { tmpLocaleID = EMPTY_STRING; } else { - tmpLocaleID = UND_PATTERN.matcher(localeID).replaceFirst(EMPTY_STRING); + tmpLocaleID = stripLeadingUnd(localeID); } return nameCache.getInstance(tmpLocaleID, null /* unused */); } /** + * Strips out the leading "und" language code case-insensitively. + * + * @implNote Avoids creating new local non-primitive objects to reduce GC pressure. + */ + private static String stripLeadingUnd(String localeID) { + int length = localeID.length(); + if (length < 3) { + return localeID; + } + + // If not starts with "und", return. + if (!localeID.regionMatches(/*ignoreCase=*/true, 0, "und", 0, /*len=*/3)) { + return localeID; + } + + // The string is equals to "und" case-insensitively. + if (length == 3) { + return EMPTY_STRING; + } + + // localeID must have a length >= 4 + char separator = localeID.charAt(3); + if (separator == '-' || separator == '_') { // "und-*" or "und_*" + return localeID.substring(3); + } + + return localeID; + } + + /** * Returns a string representation of this object. * @return a string representation of the object. */ |