Implemented typo recognition in Chrome for Android.

chrome/android/java/src/org/chromium/chrome/browser/spellchecker/SpellCheckerSessionBridge.java

Index: chrome/android/java/src/org/chromium/chrome/browser/spellchecker/SpellCheckerSessionBridge.java
diff --git a/chrome/android/java/src/org/chromium/chrome/browser/spellchecker/SpellCheckerSessionBridge.java b/chrome/android/java/src/org/chromium/chrome/browser/spellchecker/SpellCheckerSessionBridge.java
new file mode 100644
index 0000000000000000000000000000000000000000..624b5e024f79286764083bddda1853a367a1c0f1
--- /dev/null
+++ b/chrome/android/java/src/org/chromium/chrome/browser/spellchecker/SpellCheckerSessionBridge.java
@@ -0,0 +1,115 @@
+// Copyright 2015 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+package org.chromium.chrome.browser.spellchecker;
+
+import android.content.Context;
+import android.view.textservice.SentenceSuggestionsInfo;
+import android.view.textservice.SpellCheckerSession;
+import android.view.textservice.SpellCheckerSession.SpellCheckerSessionListener;
+import android.view.textservice.SuggestionsInfo;
+import android.view.textservice.TextInfo;
+import android.view.textservice.TextServicesManager;
+
+import org.chromium.base.ApplicationStatus;
+import org.chromium.base.annotations.CalledByNative;
+
+import java.util.ArrayList;
+
+/**
+ * JNI interface for native SpellCheckerSessionBridge to use Android's spellchecker.
+ */
+public class SpellCheckerSessionBridge implements SpellCheckerSessionListener {
+    private final long mNativeSpellCheckerSessionBridge;
+    private final SpellCheckerSession mSpellCheckerSession;
+
+    /**
+     * Constructs a SpellCheckerSessionBridge object as well as its SpellCheckerSession object.
+     * @param nativeSpellCheckerSessionBridge Pointer to the native SpellCheckerSessionBridge.
+     */
+    private SpellCheckerSessionBridge(long nativeSpellCheckerSessionBridge) {
+        mNativeSpellCheckerSessionBridge = nativeSpellCheckerSessionBridge;
+
+        Context context = ApplicationStatus.getApplicationContext();
+        final TextServicesManager textServicesManager =
+                (TextServicesManager) context.getSystemService(
+                        Context.TEXT_SERVICES_MANAGER_SERVICE);
+
+        // This combination of parameters will cause the spellchecker to be based off of
+        // the language specified at "Settings > Language & input > Spell checker > Language".
+        // If that setting is set to "Use system language" and the system language is not on the
+        // list of supported spellcheck languages, this call will return null.  This call will also
+        // return null if the user has turned spellchecking off at "Settings > Language & input >
+        // Spell checker".
+        mSpellCheckerSession = textServicesManager.newSpellCheckerSession(null, null, this, true);
+    }
+
+    /**
+     * Returns a new SpellCheckerSessionBridge object if the internal SpellCheckerSession object
+     * was able to be created.
+     * @param nativeSpellCheckerSessionBridge Pointer to the native SpellCheckerSessionBridge.
+     */
+    @CalledByNative
+    private static SpellCheckerSessionBridge create(long nativeSpellCheckerSessionBridge) {
+        SpellCheckerSessionBridge bridge =
+                new SpellCheckerSessionBridge(nativeSpellCheckerSessionBridge);
+        if (bridge.mSpellCheckerSession == null) {
+            return null;
+        }
+        return bridge;
+    }
+
+    /**
+     * Queries the input text against the SpellCheckerSession.
+     * @param text Text to be queried.
+     */
+    @CalledByNative
+    private void requestTextCheck(String text) {
+        mSpellCheckerSession.getSentenceSuggestions(new TextInfo[] {new TextInfo(text)}, 0);
+    }
+
+    /**
+     * Checks for typos and sends results back to native through a JNI call.
+     * @param results Results returned by the Android spellchecker.
+     */
+    @Override
+    public void onGetSentenceSuggestions(SentenceSuggestionsInfo[] results) {
+        ArrayList<Integer> offsets = new ArrayList<Integer>();
+        ArrayList<Integer> lengths = new ArrayList<Integer>();
+
+        for (SentenceSuggestionsInfo result : results) {
+            for (int i = 0; i < result.getSuggestionsCount(); i++) {
+                // If a word looks like a typo, record its offset and length.
+                if ((result.getSuggestionsInfoAt(i).getSuggestionsAttributes()
+                        & SuggestionsInfo.RESULT_ATTR_LOOKS_LIKE_TYPO)
+                        == SuggestionsInfo.RESULT_ATTR_LOOKS_LIKE_TYPO) {
+                    offsets.add(result.getOffsetAt(i));
+                    lengths.add(result.getLengthAt(i));
+                }
+            }
+        }
+
+        nativeProcessSpellCheckResults(mNativeSpellCheckerSessionBridge,
+                convertListToArray(offsets), convertListToArray(lengths));
+    }
+
+    /**
+     * Helper method to convert an ArrayList of Integer objects into an array of primitive ints
+     * for easier JNI handling of these objects on the native side.
+     * @param list List to be converted to an array.
+     */
+    private int[] convertListToArray(ArrayList<Integer> list) {
+        int[] array = new int[list.size()];
+        for (int index = 0; index < array.length; index++) {
+            array[index] = list.get(index).intValue();
+        }
+        return array;
+    }
+
+    @Override
+    public void onGetSuggestions(SuggestionsInfo[] results) {}
+
+    private native void nativeProcessSpellCheckResults(
+            long nativeSpellCheckerSessionBridge, int[] offsets, int[] lengths);
+}