1 files changed, 116 insertions, 0 deletions
diff --git a/intl/icu/source/common/mlbe.h b/intl/icu/source/common/mlbe.h
new file mode 100644
index 0000000000..38de47e5f5
--- /dev/null
+++ b/intl/icu/source/common/mlbe.h
@@ -0,0 +1,116 @@
+// © 2022 and later: Unicode, Inc. and others.
+// License & terms of use: http://www.unicode.org/copyright.html
+
+#ifndef MLBREAKENGINE_H
+#define MLBREAKENGINE_H
+
+#include "hash.h"
+#include "unicode/resbund.h"
+#include "unicode/uniset.h"
+#include "unicode/utext.h"
+#include "uvectr32.h"
+
+U_NAMESPACE_BEGIN
+
+#if !UCONFIG_NO_BREAK_ITERATION
+
+/**
+ * A machine learning break engine for the phrase breaking in Japanese.
+ */
+class MlBreakEngine : public UMemory {
+   public:
+    /**
+     * Constructor.
+     *
+     * @param digitOrOpenPunctuationOrAlphabetSet An UnicodeSet with the digit, open punctuation and
+     * alphabet.
+     * @param closePunctuationSet An UnicodeSet with close punctuation.
+     * @param status Information on any errors encountered.
+     */
+    MlBreakEngine(const UnicodeSet &digitOrOpenPunctuationOrAlphabetSet,
+                  const UnicodeSet &closePunctuationSet, UErrorCode &status);
+
+    /**
+     * Virtual destructor.
+     */
+    virtual ~MlBreakEngine();
+
+   public:
+    /**
+     * Divide up a range of characters handled by this break engine.
+     *
+     * @param inText A UText representing the text
+     * @param rangeStart The start of the range of the characters
+     * @param rangeEnd The end of the range of the characters
+     * @param foundBreaks Output of C array of int32_t break positions, or 0
+     * @param inString The normalized string of text ranging from rangeStart to rangeEnd
+     * @param inputMap The vector storing the native index of inText
+     * @param status Information on any errors encountered.
+     * @return The number of breaks found
+     */
+    int32_t divideUpRange(UText *inText, int32_t rangeStart, int32_t rangeEnd,
+                          UVector32 &foundBreaks, const UnicodeString &inString,
+                          const LocalPointer<UVector32> &inputMap, UErrorCode &status) const;
+
+   private:
+    /**
+     * Load the machine learning's model file.
+     *
+     * @param error Information on any errors encountered.
+     */
+    void loadMLModel(UErrorCode &error);
+
+    /**
+     * In the machine learning's model file, specify the name of the key and value to load the
+     * corresponding feature and its score.
+     *
+     * @param rb A ResouceBundle corresponding to the model file.
+     * @param keyName The kay name in the model file.
+     * @param valueName The value name in the model file.
+     * @param model A hashtable to store the pairs of the feature and its score.
+     * @param error Information on any errors encountered.
+     */
+    void initKeyValue(UResourceBundle *rb, const char *keyName, const char *valueName,
+                      Hashtable &model, UErrorCode &error);
+
+    /**
+     * Initialize the index list from the input string.
+     *
+     * @param inString A input string to be segmented.
+     * @param indexList A code unit index list of inString.
+     * @param status Information on any errors encountered.
+     * @return The number of code units of the first four characters in inString.
+     */
+    int32_t initIndexList(const UnicodeString &inString, int32_t *indexList,
+                          UErrorCode &status) const;
+
+    /**
+     * Evaluate whether the index is a potential breakpoint.
+     *
+     * @param inString A input string to be segmented.
+     * @param indexList A code unit index list of the inString.
+     * @param startIdx The start index of the indexList.
+     * @param numCodeUnits  The current code unit boundary of the indexList.
+     * @param numBreaks The accumulated number of breakpoints.
+     * @param boundary A vector including the index of the breakpoint.
+     * @param status Information on any errors encountered.
+     * @return The number of breakpoints
+     */
+    int32_t evaluateBreakpoint(const UnicodeString &inString, int32_t *indexList, int32_t startIdx,
+                               int32_t numCodeUnits, int32_t numBreaks, UVector32 &boundary,
+                               UErrorCode &status) const;
+
+    void printUnicodeString(const UnicodeString &s) const;
+
+    UnicodeSet fDigitOrOpenPunctuationOrAlphabetSet;
+    UnicodeSet fClosePunctuationSet;
+    Hashtable fModel[13];  // {UW1, UW2, ... UW6, BW1, ... BW3, TW1, TW2, ... TW4} 6+3+4= 13
+    int32_t fNegativeSum;
+};
+
+#endif
+
+U_NAMESPACE_END
+
+/* MLBREAKENGINE_H */
+#endif