diff --git a/java/src/com/android/inputmethod/latin/ContactsBinaryDictionary.java b/java/src/com/android/inputmethod/latin/ContactsBinaryDictionary.java
index 3fb76b142b5c70c2dad6d637ad68feac13d4020e..538bfc06f1f3fe3e2c1d3e9c55f87bf31699975e 100644
--- a/java/src/com/android/inputmethod/latin/ContactsBinaryDictionary.java
+++ b/java/src/com/android/inputmethod/latin/ContactsBinaryDictionary.java
@@ -224,7 +224,7 @@ public class ContactsBinaryDictionary extends ExpandableBinaryDictionary {
*/
private void addNameLocked(final String name) {
int len = StringUtils.codePointCount(name);
- PrevWordsInfo prevWordsInfo = new PrevWordsInfo(null);
+ PrevWordsInfo prevWordsInfo = PrevWordsInfo.EMPTY_PREV_WORDS_INFO;
// TODO: Better tokenization for non-Latin writing systems
for (int i = 0; i < len; i++) {
if (Character.isLetter(name.codePointAt(i))) {
diff --git a/java/src/com/android/inputmethod/latin/PrevWordsInfo.java b/java/src/com/android/inputmethod/latin/PrevWordsInfo.java
index 3494d16f75f16f25930b5ff39cfc8a2a11cfb285..e44239f1d059f7749bfd9a3680ce08467a738b1e 100644
--- a/java/src/com/android/inputmethod/latin/PrevWordsInfo.java
+++ b/java/src/com/android/inputmethod/latin/PrevWordsInfo.java
@@ -16,20 +16,27 @@
package com.android.inputmethod.latin;
-import android.util.Log;
-
+/**
+ * Class to represent information of previous words. This class is used to add n-gram entries
+ * into binary dictionaries, to get predictions, and to get suggestions.
+ */
// TODO: Support multiple previous words for n-gram.
public class PrevWordsInfo {
+ public static final PrevWordsInfo EMPTY_PREV_WORDS_INFO = new PrevWordsInfo(null);
public static final PrevWordsInfo BEGINNING_OF_SENTENCE = new PrevWordsInfo();
- // The previous word. May be null after resetting and before starting a new composing word, or
- // when there is no context like at the start of text for example. It can also be set to null
- // externally when the user enters a separator that does not let bigrams across, like a period
- // or a comma.
+ // The word immediately before the considered word. null means we don't have any context
+ // including the "beginning of sentence context" - we just don't know what to predict.
+ // An example of that is after a comma.
+ // For simplicity of implementation, this may also be null transiently after the WordComposer
+ // was reset and before starting a new composing word, but we should never be calling
+ // getSuggetions* in this situation.
+ // This is an empty string when mIsBeginningOfSentence is true.
public final String mPrevWord;
// TODO: Have sentence separator.
- // Whether the current context is beginning of sentence or not.
+ // Whether the current context is beginning of sentence or not. This is true when composing at
+ // the beginning of an input field or composing a word after a sentence separator.
public final boolean mIsBeginningOfSentence;
// Beginning of sentence.
diff --git a/java/src/com/android/inputmethod/latin/RichInputConnection.java b/java/src/com/android/inputmethod/latin/RichInputConnection.java
index 2c54e10aa19861c87e93f1202e5d9b5d39883f7b..e7c16360656ce4253f15a712de63c46145b72009 100644
--- a/java/src/com/android/inputmethod/latin/RichInputConnection.java
+++ b/java/src/com/android/inputmethod/latin/RichInputConnection.java
@@ -542,7 +542,7 @@ public final class RichInputConnection {
final SpacingAndPunctuations spacingAndPunctuations, final int n) {
mIC = mParent.getCurrentInputConnection();
if (null == mIC) {
- return new PrevWordsInfo(null);
+ return PrevWordsInfo.EMPTY_PREV_WORDS_INFO;
}
final CharSequence prev = getTextBeforeCursor(LOOKBACK_CHARACTER_NUM, 0);
if (DEBUG_PREVIOUS_TEXT && null != prev) {
@@ -588,30 +588,30 @@ public final class RichInputConnection {
// (n = 2) "abc. def|" -> beginning-of-sentence
public static PrevWordsInfo getPrevWordsInfoFromNthPreviousWord(final CharSequence prev,
final SpacingAndPunctuations spacingAndPunctuations, final int n) {
- if (prev == null) return new PrevWordsInfo(null);
+ if (prev == null) return PrevWordsInfo.EMPTY_PREV_WORDS_INFO;
final String[] w = spaceRegex.split(prev);
// If we can't find n words, or we found an empty word, the context is
// beginning-of-sentence.
if (w.length < n) {
- return new PrevWordsInfo();
+ return PrevWordsInfo.BEGINNING_OF_SENTENCE;
}
final String nthPrevWord = w[w.length - n];
final int length = nthPrevWord.length();
if (length <= 0) {
- return new PrevWordsInfo();
+ return PrevWordsInfo.BEGINNING_OF_SENTENCE;
}
// If ends in a sentence separator, the context is beginning-of-sentence.
final char lastChar = nthPrevWord.charAt(length - 1);
if (spacingAndPunctuations.isSentenceSeparator(lastChar)) {
- new PrevWordsInfo();
+ return PrevWordsInfo.BEGINNING_OF_SENTENCE;
}
// If ends in a word separator or connector, the context is unclear.
// TODO: Return meaningful context for this case.
if (spacingAndPunctuations.isWordSeparator(lastChar)
|| spacingAndPunctuations.isWordConnector(lastChar)) {
- return new PrevWordsInfo(null);
+ return PrevWordsInfo.EMPTY_PREV_WORDS_INFO;
}
return new PrevWordsInfo(nthPrevWord);
}
diff --git a/java/src/com/android/inputmethod/latin/WordComposer.java b/java/src/com/android/inputmethod/latin/WordComposer.java
index 6ecb37346e0fb8b2211fd5468f09717e196ca846..c53a8fda4883d0b845cedeb49a409696b64e57e4 100644
--- a/java/src/com/android/inputmethod/latin/WordComposer.java
+++ b/java/src/com/android/inputmethod/latin/WordComposer.java
@@ -85,7 +85,7 @@ public final class WordComposer {
mIsBatchMode = false;
mCursorPositionWithinWord = 0;
mRejectedBatchModeSuggestion = null;
- mPrevWordsInfo = new PrevWordsInfo(null);
+ mPrevWordsInfo = PrevWordsInfo.EMPTY_PREV_WORDS_INFO;
refreshTypedWordCache();
}
@@ -117,7 +117,7 @@ public final class WordComposer {
mIsBatchMode = false;
mCursorPositionWithinWord = 0;
mRejectedBatchModeSuggestion = null;
- mPrevWordsInfo = new PrevWordsInfo(null);
+ mPrevWordsInfo = PrevWordsInfo.EMPTY_PREV_WORDS_INFO;
refreshTypedWordCache();
}
@@ -445,7 +445,7 @@ public final class WordComposer {
// when the user inputs a separator that's not whitespace (including the case of the
// double-space-to-period feature).
public void discardPreviousWordForSuggestion() {
- mPrevWordsInfo = new PrevWordsInfo(null);
+ mPrevWordsInfo = PrevWordsInfo.EMPTY_PREV_WORDS_INFO;
}
public void resumeSuggestionOnLastComposedWord(final LastComposedWord lastComposedWord,
diff --git a/java/src/com/android/inputmethod/latin/inputlogic/InputLogic.java b/java/src/com/android/inputmethod/latin/inputlogic/InputLogic.java
index 78d4bc8076c19e06cfeb9042520532cce8c20981..d6d29a8209b275d95003664cd433f5bcd821e6e9 100644
--- a/java/src/com/android/inputmethod/latin/inputlogic/InputLogic.java
+++ b/java/src/com/android/inputmethod/latin/inputlogic/InputLogic.java
@@ -1612,8 +1612,9 @@ public final class InputLogic {
return mConnection.getPrevWordsInfoFromNthPreviousWord(
spacingAndPunctuations, nthPreviousWord);
} else {
- return LastComposedWord.NOT_A_COMPOSED_WORD == mLastComposedWord ? new PrevWordsInfo()
- : new PrevWordsInfo(mLastComposedWord.mCommittedWord.toString());
+ return LastComposedWord.NOT_A_COMPOSED_WORD == mLastComposedWord ?
+ PrevWordsInfo.BEGINNING_OF_SENTENCE :
+ new PrevWordsInfo(mLastComposedWord.mCommittedWord.toString());
}
}
diff --git a/java/src/com/android/inputmethod/latin/utils/LanguageModelParam.java b/java/src/com/android/inputmethod/latin/utils/LanguageModelParam.java
index 430efdd19c3b2c890ef9244830bf2e90ddfb04ff..9c759edb6d13a5c784a6dae6fb502727c9e517a0 100644
--- a/java/src/com/android/inputmethod/latin/utils/LanguageModelParam.java
+++ b/java/src/com/android/inputmethod/latin/utils/LanguageModelParam.java
@@ -87,7 +87,7 @@ public final class LanguageModelParam {
final ArrayList<LanguageModelParam> languageModelParams =
CollectionUtils.newArrayList();
final int N = tokens.size();
- PrevWordsInfo prevWordsInfo = new PrevWordsInfo(null);
+ PrevWordsInfo prevWordsInfo = PrevWordsInfo.EMPTY_PREV_WORDS_INFO;
for (int i = 0; i < N; ++i) {
final String tempWord = tokens.get(i);
if (StringUtils.isEmptyStringOrWhiteSpaces(tempWord)) {
@@ -104,7 +104,7 @@ public final class LanguageModelParam {
+ tempWord + "\"");
}
// Sentence terminator found. Split.
- prevWordsInfo = new PrevWordsInfo(null);
+ prevWordsInfo = PrevWordsInfo.EMPTY_PREV_WORDS_INFO;
continue;
}
if (DEBUG_TOKEN) {
diff --git a/tests/src/com/android/inputmethod/latin/DistracterFilterTest.java b/tests/src/com/android/inputmethod/latin/DistracterFilterTest.java
index ddbc8ac341c69195075cf4a91a826b7c928cd28c..33f37946721da48d51d8d3b93d7651f0bc5cddab 100644
--- a/tests/src/com/android/inputmethod/latin/DistracterFilterTest.java
+++ b/tests/src/com/android/inputmethod/latin/DistracterFilterTest.java
@@ -37,7 +37,7 @@ public class DistracterFilterTest extends InputTestsBase {
}
public void testIsDistractorToWordsInDictionaries() {
- final PrevWordsInfo EMPTY_PREV_WORDS_INFO = new PrevWordsInfo(null);
+ final PrevWordsInfo EMPTY_PREV_WORDS_INFO = PrevWordsInfo.EMPTY_PREV_WORDS_INFO;
final Locale localeEnUs = new Locale("en", "US");
String typedWord = "alot";
diff --git a/tests/src/com/android/inputmethod/latin/WordComposerTests.java b/tests/src/com/android/inputmethod/latin/WordComposerTests.java
index 17e71854110c422f988e414dcc0c7c84590515b7..274555a03bc71021f4e34a3c0aa69771e89c7547 100644
--- a/tests/src/com/android/inputmethod/latin/WordComposerTests.java
+++ b/tests/src/com/android/inputmethod/latin/WordComposerTests.java
@@ -74,7 +74,7 @@ public class WordComposerTests extends AndroidTestCase {
CoordinateUtils.newCoordinateArray(CODEPOINTS_WITH_SUPPLEMENTARY_CHAR.length,
Constants.NOT_A_COORDINATE, Constants.NOT_A_COORDINATE);
wc.setComposingWord(CODEPOINTS_WITH_SUPPLEMENTARY_CHAR, COORDINATES_WITH_SUPPLEMENTARY_CHAR,
- new PrevWordsInfo(null));
+ PrevWordsInfo.EMPTY_PREV_WORDS_INFO);
assertEquals(wc.size(), CODEPOINTS_WITH_SUPPLEMENTARY_CHAR.length);
assertFalse(wc.isCursorFrontOrMiddleOfComposingWord());
wc.setCursorPositionWithinWord(3);
@@ -109,7 +109,7 @@ public class WordComposerTests extends AndroidTestCase {
assertEquals(PREV_WORDS_INFO_STR_WITHIN_BMP, wc.getPrevWordsInfoForSuggestion());
- final PrevWordsInfo PREV_WORDS_INFO_NULL = new PrevWordsInfo(null);
+ final PrevWordsInfo PREV_WORDS_INFO_NULL = PrevWordsInfo.EMPTY_PREV_WORDS_INFO;
wc.setComposingWord(CODEPOINTS_WITH_SUPPLEMENTARY_CHAR, COORDINATES_WITH_SUPPLEMENTARY_CHAR,
PREV_WORDS_INFO_NULL);
wc.setCursorPositionWithinWord(3);
diff --git a/tests/src/com/android/inputmethod/latin/personalization/UserHistoryDictionaryTests.java b/tests/src/com/android/inputmethod/latin/personalization/UserHistoryDictionaryTests.java
index bc8686410ec7f4be6c894fcd416e91020a2b97f3..7d3214a3d1737322bba8792b7818bc4073dc4060 100644
--- a/tests/src/com/android/inputmethod/latin/personalization/UserHistoryDictionaryTests.java
+++ b/tests/src/com/android/inputmethod/latin/personalization/UserHistoryDictionaryTests.java
@@ -110,7 +110,7 @@ public class UserHistoryDictionaryTests extends AndroidTestCase {
}
private static void addToDict(final UserHistoryDictionary dict, final List<String> words) {
- PrevWordsInfo prevWordsInfo = new PrevWordsInfo(null);
+ PrevWordsInfo prevWordsInfo = PrevWordsInfo.EMPTY_PREV_WORDS_INFO;
for (String word : words) {
UserHistoryDictionary.addToDictionary(dict, prevWordsInfo, word, true,
(int)TimeUnit.MILLISECONDS.toSeconds(System.currentTimeMillis()));