Merge "Introduce script matching for enabling default IME subtypes." into nyc-dev (8f2041cb) · Commits · e / os / android_frameworks_base

core/java/com/android/internal/inputmethod/LocaleUtils.java

+158 −74

Original line number	Diff line number	Diff line
		@@ -18,15 +18,17 @@ package com.android.internal.inputmethod;

		import com.android.internal.annotations.VisibleForTesting;

		import android.annotation.IntRange;
		import android.annotation.NonNull;
		import android.annotation.Nullable;
		import android.text.TextUtils;
		import android.icu.util.ULocale;
		import android.util.LocaleList;

		import java.util.ArrayList;
		import java.util.Arrays;
		import java.util.HashMap;
		import java.util.List;
		import java.util.Locale;
		import java.util.Objects;

		public final class LocaleUtils {

		@@ -36,12 +38,138 @@ public final class LocaleUtils {
		Locale get(@Nullable T source);
		}

		@Nullable
		private static String getLanguage(@Nullable Locale locale) {
		if (locale == null) {
		return null;
		/**
		* Calculates a matching score for the single desired locale.
		*
		* @see LocaleUtils#calculateMatchingScore(ULocale, LocaleList, byte[])
		*
		* @param supported The locale supported by IME subtype.
		* @param desired The locale preferred by user.
		* @return A score based on the locale matching for the default subtype enabling.
		*/
		@IntRange(from=1, to=3)
		private static byte calculateMatchingSubScore(@NonNull final ULocale supported,
		@NonNull final ULocale desired) {
		// Assuming supported/desired is fully expanded.
		if (supported.equals(desired)) {
		return 3; // Exact match.
		}

		// Skip language matching since it was already done in calculateMatchingScore.

		final String supportedScript = supported.getScript();
		if (supportedScript.isEmpty() \|\| !supportedScript.equals(desired.getScript())) {
		// TODO: Need subscript matching. For example, Hanb should match with Bopo.
		return 1;
		}

		final String supportedCountry = supported.getCountry();
		if (supportedCountry.isEmpty() \|\| !supportedCountry.equals(desired.getCountry())) {
		return 2;
		}

		// Ignore others e.g. variants, extensions.
		return 3;
		}

		/**
		* Calculates a matching score for the desired locale list.
		*
		* <p>The supported locale gets a matching score of 3 if all language, script and country of the
		* supported locale matches with the desired locale. The supported locale gets a matching
		* score of 2 if the language and script of the supported locale matches with the desired
		* locale. The supported locale gets a matching score of 1 if only language of the supported
		* locale matches with the desired locale. The supported locale gets a matching score of 0 if
		* the language of the supported locale doesn't match with the desired locale.</p>
		*
		* @param supported The locale supported by IME subtyle.
		* @param desired The locale list preferred by user. Typically system locale list.
		* @param out The output buffer to be stored the individual score for the desired language list.
		* The length of {@code out} must be same as the length of {@code desired} language list.
		* @return {@code false} if supported locale doesn't match with any desired locale list.
		* Otherwise {@code true}.
		*/
		private static boolean calculateMatchingScore(@NonNull final ULocale supported,
		@NonNull final LocaleList desired, @NonNull byte[] out) {
		if (desired.isEmpty()) {
		return false;
		}

		boolean allZeros = true;
		final int N = desired.size();
		for (int i = 0; i < N; ++i) {
		final Locale locale = desired.get(i);

		if (!locale.getLanguage().equals(supported.getLanguage())) {
		// TODO: cache the result of addLikelySubtags if it is slow.
		out[i] = 0;
		} else {
		out[i] = calculateMatchingSubScore(
		supported, ULocale.addLikelySubtags(ULocale.forLocale(locale)));
		if (allZeros && out[i] != 0) {
		allZeros = false;
		}
		}
		}
		return !allZeros;
		}

		private static final class ScoreEntry implements Comparable<ScoreEntry> {
		public int mIndex = -1;
		@NonNull public final byte[] mScore; // matching score of the i-th system languages.

		ScoreEntry(@NonNull byte[] score, int index) {
		mScore = new byte[score.length];
		set(score, index);
		}

		private void set(@NonNull byte[] score, int index) {
		for (int i = 0; i < mScore.length; ++i) {
		mScore[i] = score[i];
		}
		mIndex = index;
		}

		/**
		* Update score and index if the given score is better than this.
		*/
		public void updateIfBetter(@NonNull byte[] score, int index) {
		if (compare(mScore, score) == -1) { // mScore < score
		set(score, index);
		}
		}

		/**
		* Provides comaprison for bytes[].
		*
		* <p> Comparison does as follows. If the first value of {@code left} is larger than the
		* first value of {@code right}, {@code left} is large than {@code right}. If the first
		* value of {@code left} is less than the first value of {@code right}, {@code left} is less
		* than {@code right}. If the first value of {@code left} and the first value of
		* {@code right} is equal, do the same comparison to the next value. Finally if all values
		* in {@code left} and {@code right} are equal, {@code left} and {@code right} is equal.</p>
		*
		* @param left The length must be equal to {@code right}.
		* @param right The length must be equal to {@code left}.
		* @return 1 if {@code left} is larger than {@code right}. -1 if {@code left} is less than
		* {@code right}. 0 if {@code left} and {@code right} is equal.
		*/
		@IntRange(from=-1, to=1)
		private static int compare(@NonNull byte[] left, @NonNull byte[] right) {
		for (int i = 0; i < left.length; ++i) {
		if (left[i] > right[i]) {
		return 1;
		} else if (left[i] < right[i]) {
		return -1;
		}
		}
		return 0;
		}

		@Override
		public int compareTo(final ScoreEntry other) {
		return -1 * compare(mScore, other.mScore); // Order by descending order.
		}
		return locale.getLanguage();
		}

		/**
		@@ -52,14 +180,8 @@ public final class LocaleUtils {
		* {@code "en-GB", "ja", "en-AU", "fr-CA", "en-IN"} is specified to {@code preferredLanguages},
		* this method tries to copy at most one English locale, at most one Japanese, and at most one
		* French locale from {@code source} to {@code dest}. Here the best matching English locale
		* will be searched from {@code source} as follows.
		* <ol>
		* <li>The first instance in {@code sources} that exactly matches {@code "en-GB"}</li>
		* <li>The first instance in {@code sources} that exactly matches {@code "en-AU"}</li>
		* <li>The first instance in {@code sources} that exactly matches {@code "en-IN"}</li>
		* <li>The first instance in {@code sources} that partially matches {@code "en"}</li>
		* </ol>
		* <p>Then this method iterates the same algorithm for Japanese then French.</p>
		* will be searched from {@code source} based on matching score. For the score design, see
		* {@link LocaleUtils#calculateMatchingScore(ULocale, LocaleList, byte[])}</p>
		*
		* @param sources Source items to be filtered.
		* @param extractor Type converter from the source items to {@link Locale} object.
		@@ -74,69 +196,31 @@ public final class LocaleUtils {
		@NonNull LocaleExtractor<T> extractor,
		@NonNull LocaleList preferredLanguages,
		@NonNull ArrayList<T> dest) {
		final Locale[] availableLocales = new Locale[sources.size()];
		for (int i = 0; i < availableLocales.length; ++i) {
		availableLocales[i] = extractor.get(sources.get(i));
		}
		final Locale[] sortedPreferredLanguages = new Locale[preferredLanguages.size()];
		if (sortedPreferredLanguages.length > 0) {
		int nextIndex = 0;
		final int N = preferredLanguages.size();
		languageLoop:
		for (int i = 0; i < N; ++i) {
		final String language = getLanguage(preferredLanguages.get(i));
		for (int j = 0; j < nextIndex; ++j) {
		if (TextUtils.equals(getLanguage(sortedPreferredLanguages[j]), language)) {
		continue languageLoop;
		}
		}
		for (int j = i; j < N; ++j) {
		final Locale locale = preferredLanguages.get(j);
		if (TextUtils.equals(language, getLanguage(locale))) {
		sortedPreferredLanguages[nextIndex] = locale;
		++nextIndex;
		}
		}
		}
		}
		final HashMap<String, ScoreEntry> scoreboard = new HashMap<>();
		final byte[] score = new byte[preferredLanguages.size()];


		for (int languageIndex = 0; languageIndex < sortedPreferredLanguages.length;) {
		// Finding the range.
		final String language = getLanguage(sortedPreferredLanguages[languageIndex]);
		int nextLanguageIndex = languageIndex;
		for (; nextLanguageIndex < sortedPreferredLanguages.length; ++nextLanguageIndex) {
		final Locale locale = sortedPreferredLanguages[nextLanguageIndex];
		if (!TextUtils.equals(getLanguage(locale), language)) {
		break;
		}
		}

		// Check exact match
		boolean found = false;
		for (int i = languageIndex; !found && i < nextLanguageIndex; ++i) {
		final Locale locale = sortedPreferredLanguages[i];
		for (int j = 0; j < availableLocales.length; ++j) {
		if (!Objects.equals(locale, availableLocales[j])) {
		final int sourceSize = sources.size();
		for (int i = 0; i < sourceSize; ++i) {
		final Locale locale = extractor.get(sources.get(i));
		if (locale == null \|\|
		!calculateMatchingScore(ULocale.addLikelySubtags(ULocale.forLocale(locale)),
		preferredLanguages, score)) {
		continue;
		}
		dest.add(sources.get(j));
		found = true;
		break;
		}
		}

		if (!found) {
		// No exact match. Use language match.
		for (int j = 0; j < availableLocales.length; ++j) {
		if (!TextUtils.equals(language, getLanguage(availableLocales[j]))) {
		continue;
		}
		dest.add(sources.get(j));
		break;
		final String lang = locale.getLanguage();
		final ScoreEntry bestScore = scoreboard.get(lang);
		if (bestScore == null) {
		scoreboard.put(lang, new ScoreEntry(score, i));
		} else {
		bestScore.updateIfBetter(score, i);
		}
		}
		languageIndex = nextLanguageIndex;

		final ScoreEntry[] result = scoreboard.values().toArray(new ScoreEntry[scoreboard.size()]);
		Arrays.sort(result);
		for (final ScoreEntry entry : result) {
		dest.add(sources.get(entry.mIndex));
		}
		}
		}

core/tests/coretests/src/com/android/internal/inputmethod/LocaleUtilsTest.java

+205 −13

Original line number	Diff line number	Diff line
		@@ -49,6 +49,22 @@ public class LocaleUtilsTest extends InstrumentationTestCase {
		assertEquals(0, dest.size());
		}

		@SmallTest
		public void testFilterDoesNotMatchAnything() throws Exception {
		final ArrayList<Locale> availableLocales = new ArrayList<>();
		availableLocales.add(Locale.forLanguageTag("en-US"));
		availableLocales.add(Locale.forLanguageTag("fr-CA"));
		availableLocales.add(Locale.forLanguageTag("in"));
		availableLocales.add(Locale.forLanguageTag("ja"));
		availableLocales.add(Locale.forLanguageTag("fil"));

		final LocaleList preferredLocales = LocaleList.forLanguageTags("zh-Hans-TW");

		final ArrayList<Locale> dest = new ArrayList<>();
		LocaleUtils.filterByLanguage(availableLocales, sIdentityMapper, preferredLocales, dest);
		assertEquals(0, dest.size());
		}

		@SmallTest
		public void testFilterByLanguageEmptySource() throws Exception {
		final ArrayList<Locale> availableLocales = new ArrayList<>();
		@@ -124,6 +140,7 @@ public class LocaleUtilsTest extends InstrumentationTestCase {

		@SmallTest
		public void testFilterByLanguage() throws Exception {
		{
		final ArrayList<Locale> availableLocales = new ArrayList<>();
		availableLocales.add(Locale.forLanguageTag("en-US"));
		availableLocales.add(Locale.forLanguageTag("fr-CA"));
		@@ -140,6 +157,20 @@ public class LocaleUtilsTest extends InstrumentationTestCase {
		assertEquals(availableLocales.get(0), dest.get(1)); // "en-US"
		assertEquals(availableLocales.get(3), dest.get(2)); // "ja"
		}
		{
		final ArrayList<Locale> availableLocales = new ArrayList<>();
		availableLocales.add(Locale.forLanguageTag("en-US"));
		availableLocales.add(Locale.forLanguageTag("en-GB"));
		availableLocales.add(Locale.forLanguageTag("en-IN"));

		final LocaleList preferredLocales = LocaleList.forLanguageTags("en-US");

		final ArrayList<Locale> dest = new ArrayList<>();
		LocaleUtils.filterByLanguage(availableLocales, sIdentityMapper, preferredLocales, dest);
		assertEquals(1, dest.size());
		assertEquals(availableLocales.get(0), dest.get(0)); // "en-US"
		}
		}

		@SmallTest
		public void testFilterByLanguageTheSameLanguage() throws Exception {
		@@ -191,4 +222,165 @@ public class LocaleUtilsTest extends InstrumentationTestCase {
		assertEquals(availableLocales.get(1), dest.get(0)); // "en-CA"
		}
		}

		@SmallTest
		public void testFilterByLanguageFallbackRules() throws Exception {
		{
		final LocaleList preferredLocales = LocaleList.forLanguageTags("sr-Latn-RS");
		final ArrayList<Locale> availableLocales = new ArrayList<>();
		availableLocales.add(Locale.forLanguageTag("sr-Cyrl-BA"));
		availableLocales.add(Locale.forLanguageTag("sr-Cyrl-CS"));
		availableLocales.add(Locale.forLanguageTag("sr-Cyrl-ME"));
		availableLocales.add(Locale.forLanguageTag("sr-Cyrl-RS"));
		availableLocales.add(Locale.forLanguageTag("sr-Latn-BA"));
		availableLocales.add(Locale.forLanguageTag("sr-Latn-CS"));
		availableLocales.add(Locale.forLanguageTag("sr-Latn-ME"));
		availableLocales.add(Locale.forLanguageTag("sr-Latn-RS"));
		final ArrayList<Locale> dest = new ArrayList<>();
		LocaleUtils.filterByLanguage(availableLocales, sIdentityMapper, preferredLocales, dest);
		assertEquals(1, dest.size());
		assertEquals(availableLocales.get(7), dest.get(0)); // "sr-Latn-RS"
		}
		{
		final LocaleList preferredLocales = LocaleList.forLanguageTags("sr-Latn-RS-x-android");
		final ArrayList<Locale> availableLocales = new ArrayList<>();
		availableLocales.add(Locale.forLanguageTag("sr-Cyrl-BA"));
		availableLocales.add(Locale.forLanguageTag("sr-Cyrl-CS"));
		availableLocales.add(Locale.forLanguageTag("sr-Cyrl-ME"));
		availableLocales.add(Locale.forLanguageTag("sr-Cyrl-RS"));
		availableLocales.add(Locale.forLanguageTag("sr-Latn-BA"));
		availableLocales.add(Locale.forLanguageTag("sr-Latn-CS"));
		availableLocales.add(Locale.forLanguageTag("sr-Latn-ME"));
		availableLocales.add(Locale.forLanguageTag("sr-Latn-RS"));
		final ArrayList<Locale> dest = new ArrayList<>();
		LocaleUtils.filterByLanguage(availableLocales, sIdentityMapper, preferredLocales, dest);
		assertEquals(1, dest.size());
		assertEquals(availableLocales.get(7), dest.get(0)); // "sr-Latn-RS"
		}
		{
		final LocaleList preferredLocales = LocaleList.forLanguageTags("sr-Latn-RS");
		final ArrayList<Locale> availableLocales = new ArrayList<>();
		availableLocales.add(Locale.forLanguageTag("sr-Cyrl-BA-x-android"));
		availableLocales.add(Locale.forLanguageTag("sr-Cyrl-CS-x-android"));
		availableLocales.add(Locale.forLanguageTag("sr-Cyrl-ME-x-android"));
		availableLocales.add(Locale.forLanguageTag("sr-Cyrl-RS-x-android"));
		availableLocales.add(Locale.forLanguageTag("sr-Latn-BA-x-android"));
		availableLocales.add(Locale.forLanguageTag("sr-Latn-CS-x-android"));
		availableLocales.add(Locale.forLanguageTag("sr-Latn-ME-x-android"));
		availableLocales.add(Locale.forLanguageTag("sr-Latn-RS-x-android"));
		final ArrayList<Locale> dest = new ArrayList<>();
		LocaleUtils.filterByLanguage(availableLocales, sIdentityMapper, preferredLocales, dest);
		assertEquals(1, dest.size());
		assertEquals(availableLocales.get(7), dest.get(0)); // "sr-Latn-RS-x-android"
		}

		{
		final LocaleList preferredLocales = LocaleList.forLanguageTags("sr-Latn-RS");
		final ArrayList<Locale> availableLocales = new ArrayList<>();
		availableLocales.add(Locale.forLanguageTag("sr"));
		availableLocales.add(Locale.forLanguageTag("sr-Cyrl"));
		availableLocales.add(Locale.forLanguageTag("sr-Latn"));
		final ArrayList<Locale> dest = new ArrayList<>();
		LocaleUtils.filterByLanguage(availableLocales, sIdentityMapper, preferredLocales, dest);
		assertEquals(1, dest.size());
		assertEquals(availableLocales.get(2), dest.get(0)); // "sr-Latn"
		}

		{
		final LocaleList preferredLocales = LocaleList.forLanguageTags("sr-RS");
		final ArrayList<Locale> availableLocales = new ArrayList<>();
		availableLocales.add(Locale.forLanguageTag("sr"));
		availableLocales.add(Locale.forLanguageTag("sr-RS"));
		availableLocales.add(Locale.forLanguageTag("sr-Latn"));
		final ArrayList<Locale> dest = new ArrayList<>();
		LocaleUtils.filterByLanguage(availableLocales, sIdentityMapper, preferredLocales, dest);
		assertEquals(1, dest.size());
		assertEquals(availableLocales.get(0), dest.get(0)); // "sr"
		}

		{
		final LocaleList preferredLocales = LocaleList.forLanguageTags("sr-Latn");
		final ArrayList<Locale> availableLocales = new ArrayList<>();
		availableLocales.add(Locale.forLanguageTag("sr"));
		availableLocales.add(Locale.forLanguageTag("sr-RS"));
		availableLocales.add(Locale.forLanguageTag("sr-Latn"));
		final ArrayList<Locale> dest = new ArrayList<>();
		LocaleUtils.filterByLanguage(availableLocales, sIdentityMapper, preferredLocales, dest);
		assertEquals(1, dest.size());
		assertEquals(availableLocales.get(2), dest.get(0)); // "sr-Latn"
		}

		{
		final LocaleList preferredLocales = LocaleList.forLanguageTags("sr");
		final ArrayList<Locale> availableLocales = new ArrayList<>();
		availableLocales.add(Locale.forLanguageTag("sr"));
		availableLocales.add(Locale.forLanguageTag("sr-RS"));
		availableLocales.add(Locale.forLanguageTag("sr-Latn"));
		final ArrayList<Locale> dest = new ArrayList<>();
		LocaleUtils.filterByLanguage(availableLocales, sIdentityMapper, preferredLocales, dest);
		assertEquals(1, dest.size());
		assertEquals(availableLocales.get(0), dest.get(0)); // "sr"
		}
		{
		final LocaleList preferredLocales = LocaleList.forLanguageTags("sr");
		final ArrayList<Locale> availableLocales = new ArrayList<>();
		availableLocales.add(Locale.forLanguageTag("sr-Latn"));
		availableLocales.add(Locale.forLanguageTag("sr-RS"));
		availableLocales.add(Locale.forLanguageTag("sr"));
		final ArrayList<Locale> dest = new ArrayList<>();
		LocaleUtils.filterByLanguage(availableLocales, sIdentityMapper, preferredLocales, dest);
		assertEquals(1, dest.size());
		assertEquals(availableLocales.get(1), dest.get(0)); // "sr-RS"
		}

		{
		final LocaleList preferredLocales = LocaleList.forLanguageTags("sr");
		final ArrayList<Locale> availableLocales = new ArrayList<>();
		availableLocales.add(Locale.forLanguageTag("sr-Cyrl-RS"));
		availableLocales.add(Locale.forLanguageTag("sr-Latn-RS"));
		final ArrayList<Locale> dest = new ArrayList<>();
		LocaleUtils.filterByLanguage(availableLocales, sIdentityMapper, preferredLocales, dest);
		assertEquals(1, dest.size());
		assertEquals(availableLocales.get(0), dest.get(0)); // "sr-Cyrl-RS"
		}
		{
		final LocaleList preferredLocales = LocaleList.forLanguageTags("sr-Latn");
		final ArrayList<Locale> availableLocales = new ArrayList<>();
		availableLocales.add(Locale.forLanguageTag("sr-Latn-RS"));
		availableLocales.add(Locale.forLanguageTag("sr-Cyrl-RS"));
		final ArrayList<Locale> dest = new ArrayList<>();
		LocaleUtils.filterByLanguage(availableLocales, sIdentityMapper, preferredLocales, dest);
		assertEquals(1, dest.size());
		assertEquals(availableLocales.get(0), dest.get(0)); // "sr-Latn-RS"
		}
		}

		public void testFilterKnownLimitation() throws Exception {
		// Following test cases are not for intentional behavior but checks for preventing the
		// behavior from becoming worse.
		{
		final LocaleList preferredLocales = LocaleList.forLanguageTags("ja-Hrkt");
		final ArrayList<Locale> availableLocales = new ArrayList<>();
		availableLocales.add(Locale.forLanguageTag("ja-Jpan"));
		availableLocales.add(Locale.forLanguageTag("ja-Hrkt"));
		final ArrayList<Locale> dest = new ArrayList<>();
		LocaleUtils.filterByLanguage(availableLocales, sIdentityMapper, preferredLocales, dest);
		assertEquals(1, dest.size());
		// Should be ja-Jpan since it supports ja-Hrkt and listed before ja-Hrkt.
		assertEquals(availableLocales.get(1), dest.get(0));
		}
		{
		final LocaleList preferredLocales = LocaleList.forLanguageTags("zh-Hani");
		final ArrayList<Locale> availableLocales = new ArrayList<>();
		availableLocales.add(Locale.forLanguageTag("zh-Hans"));
		availableLocales.add(Locale.forLanguageTag("zh-Hant"));
		availableLocales.add(Locale.forLanguageTag("zh-Hanb"));
		availableLocales.add(Locale.forLanguageTag("zh-Hani"));
		final ArrayList<Locale> dest = new ArrayList<>();
		LocaleUtils.filterByLanguage(availableLocales, sIdentityMapper, preferredLocales, dest);
		assertEquals(1, dest.size());
		// Should be zh-Hans since it supports zh-Hani. Also zh-Hant, zh-Hanb supports zh-Hani.
		assertEquals(availableLocales.get(3), dest.get(0));
		}
		}
		}