Trebuchet: Use ICU4J public APIs

The private implementation of AlphabeticIndexCompat in libcore.icu
has been removed, so Trebuchet always uses BaseAlphabeticIndex,
which doesn't work properly with all the alphabets. Since Android
7.0, the Android platform exposes a subset of the ICU4J APIs, so
switch to that and drop the fallback code.

Change-Id: Id8e5538f70d074d5ffeea0c23ef3f2a72ec0f3bf

1 files changed, 14 insertions, 133 deletions

diff --git a/src/com/android/launcher3/compat/AlphabeticIndexCompat.java b/src/com/android/launcher3/compat/AlphabeticIndexCompat.java
index ee1f4d57b..c95409145 100644
--- a/src/com/android/launcher3/compat/AlphabeticIndexCompat.java
+++ b/src/com/android/launcher3/compat/AlphabeticIndexCompat.java
@@ -1,119 +1,29 @@
 package com.android.launcher3.compat;
 
 import android.content.Context;
+import android.icu.text.AlphabeticIndex;
+
 import com.android.launcher3.Utilities;
 
-import java.lang.reflect.Constructor;
-import java.lang.reflect.Method;
-import java.text.Normalizer;
 import java.util.Locale;
 
-/**
- * Fallback class to support Alphabetic indexing if not supported by the framework.
- * TODO(winsonc): disable for non-english locales
- */
-class BaseAlphabeticIndex {
-
-    private static final String BUCKETS = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ-";
-    private static final int UNKNOWN_BUCKET_INDEX = BUCKETS.length() - 1;
-
-    public BaseAlphabeticIndex() {}
-
-    /**
-     * Sets the max number of the label buckets in this index.
-     */
-    public void setMaxLabelCount(int count) {
-        // Not currently supported
-    }
-
-    /**
-     * Returns the index of the bucket in which the given string should appear.
-     */
-    protected int getBucketIndex(String s) {
-        if (s.isEmpty()) {
-            return UNKNOWN_BUCKET_INDEX;
-        }
-        String asciiName = Normalizer.normalize(s, Normalizer.Form.NFD)
-            .replaceAll("[^\\p{ASCII}]", "");
-        if (asciiName.isEmpty()) {
-            return UNKNOWN_BUCKET_INDEX;
-        }
-        int index = BUCKETS.indexOf(asciiName.substring(0, 1).toUpperCase());
-        if (index != -1) {
-            return index;
-        }
-        return UNKNOWN_BUCKET_INDEX;
-    }
-
-    /**
-     * Returns the label for the bucket at the given index (as returned by getBucketIndex).
-     */
-    protected String getBucketLabel(int index) {
-        return BUCKETS.substring(index, index + 1);
-    }
-}
-
-/**
- * Reflected libcore.icu.AlphabeticIndex implementation, falls back to the base alphabetic index.
- */
-public class AlphabeticIndexCompat extends BaseAlphabeticIndex {
+public class AlphabeticIndexCompat {
 
     private static final String MID_DOT = "\u2219";
 
-    private Object mAlphabeticIndex;
-    private Method mAddLabelsMethod;
-    private Method mSetMaxLabelCountMethod;
-    private Method mGetBucketIndexMethod;
-    private Method mGetBucketLabelMethod;
-    private boolean mHasValidAlphabeticIndex;
+    private AlphabeticIndex.ImmutableIndex mAlphabeticIndex;
     private String mDefaultMiscLabel;
 
     public AlphabeticIndexCompat(Context context) {
-        super();
-        try {
-            Locale curLocale = context.getResources().getConfiguration().locale;
-            Class clazz = Class.forName("libcore.icu.AlphabeticIndex");
-            Constructor ctor = clazz.getConstructor(Locale.class);
-            mAddLabelsMethod = clazz.getDeclaredMethod("addLabels", Locale.class);
-            mSetMaxLabelCountMethod = clazz.getDeclaredMethod("setMaxLabelCount", int.class);
-            mGetBucketIndexMethod = clazz.getDeclaredMethod("getBucketIndex", String.class);
-            mGetBucketLabelMethod = clazz.getDeclaredMethod("getBucketLabel", int.class);
-            mAlphabeticIndex = ctor.newInstance(curLocale);
-            try {
-                // Ensure we always have some base English locale buckets
-                if (!curLocale.getLanguage().equals(Locale.ENGLISH.getLanguage())) {
-                    mAddLabelsMethod.invoke(mAlphabeticIndex, Locale.ENGLISH);
-                }
-            } catch (Exception e) {
-                e.printStackTrace();
-            }
-            if (curLocale.getLanguage().equals(Locale.JAPANESE.getLanguage())) {
-                // Japanese character 他 ("misc")
-                mDefaultMiscLabel = "\u4ed6";
-                // TODO(winsonc, omakoto): We need to handle Japanese sections better, especially the kanji
-            } else {
-                // Dot
-                mDefaultMiscLabel = MID_DOT;
-            }
-            mHasValidAlphabeticIndex = true;
-        } catch (Exception e) {
-            mHasValidAlphabeticIndex = false;
-        }
-    }
-
-    /**
-     * Sets the max number of the label buckets in this index.
-     * (ICU 51 default is 99)
-     */
-    public void setMaxLabelCount(int count) {
-        if (mHasValidAlphabeticIndex) {
-            try {
-                mSetMaxLabelCountMethod.invoke(mAlphabeticIndex, count);
-            } catch (Exception e) {
-                e.printStackTrace();
-            }
+        Locale curLocale = context.getResources().getConfiguration().getLocales().get(0);
+        mAlphabeticIndex = new AlphabeticIndex(curLocale).buildImmutableIndex();
+        if (curLocale.getLanguage().equals(Locale.JAPANESE.getLanguage())) {
+            // Japanese character 他 ("misc")
+            mDefaultMiscLabel = "\u4ed6";
+            // TODO(winsonc, omakoto): We need to handle Japanese sections better, especially the kanji
         } else {
-            super.setMaxLabelCount(count);
+            // Dot
+            mDefaultMiscLabel = MID_DOT;
         }
     }
 
@@ -122,7 +32,8 @@ public class AlphabeticIndexCompat extends BaseAlphabeticIndex {
      */
     public String computeSectionName(CharSequence cs) {
         String s = Utilities.trim(cs);
-        String sectionName = getBucketLabel(getBucketIndex(s));
+        int bucketIndex = mAlphabeticIndex.getBucketIndex(s);
+        String sectionName = mAlphabeticIndex.getBucket(bucketIndex).getLabel();
         if (Utilities.trim(sectionName).isEmpty()) {
             if (s.length() > 0) {
                 int c = s.codePointAt(0);
@@ -149,34 +60,4 @@ public class AlphabeticIndexCompat extends BaseAlphabeticIndex {
         }
         return sectionName;
     }
-
-    /**
-     * Returns the index of the bucket in which {@param s} should appear.
-     * Function is synchronized because underlying routine walks an iterator
-     * whose state is maintained inside the index object.
-     */
-    protected int getBucketIndex(String s) {
-        if (mHasValidAlphabeticIndex) {
-            try {
-                return (Integer) mGetBucketIndexMethod.invoke(mAlphabeticIndex, s);
-            } catch (Exception e) {
-                e.printStackTrace();
-            }
-        }
-        return super.getBucketIndex(s);
-    }
-
-    /**
-     * Returns the label for the bucket at the given index (as returned by getBucketIndex).
-     */
-    protected String getBucketLabel(int index) {
-        if (mHasValidAlphabeticIndex) {
-            try {
-                return (String) mGetBucketLabelMethod.invoke(mAlphabeticIndex, index);
-            } catch (Exception e) {
-                e.printStackTrace();
-            }
-        }
-        return super.getBucketLabel(index);
-    }
 }