[Android] Introduce a Java wrapper for TemplateUrlService.

chrome/android/java/src/org/chromium/chrome/browser/search_engines/TemplateUrlService.java

Index: chrome/android/java/src/org/chromium/chrome/browser/search_engines/TemplateUrlService.java
diff --git a/chrome/android/java/src/org/chromium/chrome/browser/search_engines/TemplateUrlService.java b/chrome/android/java/src/org/chromium/chrome/browser/search_engines/TemplateUrlService.java
new file mode 100644
index 0000000000000000000000000000000000000000..9cea47d5aa03d2077dccd7bea8ea24e9344aa557
--- /dev/null
+++ b/chrome/android/java/src/org/chromium/chrome/browser/search_engines/TemplateUrlService.java
@@ -0,0 +1,124 @@
+// Copyright (c) 2013 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.search_engines;
+
+import org.chromium.base.CalledByNative;
+import org.chromium.base.ThreadUtils;
+
+import java.util.ArrayList;
+import java.util.HashMap;
+import java.util.List;
+
+/**
+ * Android wrapper of the TemplateUrlService which provides access from the Java
+ * layer.
+ *
+ * Only usable from the UI thread as it's primary purpose is for supporting the Android
+ * preferences UI.
+ *
+ * See chrome/browser/search_engines/template_url_service.h for more details.
+ */
+public class TemplateUrlService {
+
+    // Keys for localized search engines.
+    // MUST match static strings defined in template_url_service_android.cc
+    public static final String SEARCH_ENGINE_ID = "searchEngineId";
+    public static final String SEARCH_ENGINE_URL = "searchEngineUrl";
+    public static final String SEARCH_ENGINE_KEYWORD = "searchEngineKeyword";
+    public static final String SEARCH_ENGINE_SHORT_NAME = "searchEngineShortName";
+
+    /**
+     * This listener will be notified when template url service is done laoding.
+     */
+    public interface LoadListener {
+        public abstract void onTemplateUrlServiceLoaded();
+    }
+
+    private static TemplateUrlService sService;
+
+    public static TemplateUrlService getInstance() {
+        ThreadUtils.assertOnUiThread();
+        if (sService == null) {
+            sService = new TemplateUrlService();
+        }
+        return sService;
+    }
+
+    private final int mNativeTemplateUrlServiceAndroid;
+    private final List<LoadListener> mLoadListeners = new ArrayList<LoadListener>();
+
+    private TemplateUrlService() {
+        // Note that this technically leaks the native object, however, TemlateUrlService
+        // is a singleton that lives forever and there's no clean shutdown of Chrome on Android
+        mNativeTemplateUrlServiceAndroid = nativeInit();
+    }
+
+    public boolean isLoaded() {
+        ThreadUtils.assertOnUiThread();
+        return nativeIsLoaded(mNativeTemplateUrlServiceAndroid);
+    }
+
+    public void load() {
+        ThreadUtils.assertOnUiThread();
+        nativeLoad(mNativeTemplateUrlServiceAndroid);
+    }
+
+    /**
+     * Get the hash map of the localized search engines.
+     */
+    public HashMap<String,String>[] getLocalizedSearchEngines() {
+        ThreadUtils.assertOnUiThread();
+        return nativeGetLocalizedSearchEngines(mNativeTemplateUrlServiceAndroid);
+    }
+
+    /**
+     * Called from native when template URL service is done loading.
+     */
+    @CalledByNative
+    private void templateUrlServiceLoaded() {
+        ThreadUtils.assertOnUiThread();
+        for (LoadListener listener : mLoadListeners) {
+            listener.onTemplateUrlServiceLoaded();
+        }
+    }
+
+    public int getSearchEngine() {
+        ThreadUtils.assertOnUiThread();
+        return nativeGetSearchEngine(mNativeTemplateUrlServiceAndroid);
+    }
+
+    public void setSearchEngine(int selectedIndex) {
+        ThreadUtils.assertOnUiThread();
+        nativeSetSearchEngine(mNativeTemplateUrlServiceAndroid, selectedIndex);
+    }
+
+    /**
+     * Registers a listener for the TEMPLATE_URL_SERVICE_LOADED notification.
+     */
+    public void registerLoadListener(LoadListener listener) {
+        ThreadUtils.assertOnUiThread();
+        assert !mLoadListeners.contains(listener);
+        mLoadListeners.add(listener);
+    }
+
+    /**
+     * Unregisters a listener for the TEMPLATE_URL_SERVICE_LOADED notification.
+     */
+    public void unregisterLoadListener(LoadListener listener) {
+        ThreadUtils.assertOnUiThread();
+        assert (mLoadListeners.size() > 0);
+        assert (mLoadListeners.contains(listener));
+        mLoadListeners.remove(listener);
+    }
+
+    private native int nativeInit();
+    private native void nativeLoad(int nativeTemplateUrlServiceAndroid);
+    private native boolean nativeIsLoaded(int nativeTemplateUrlServiceAndroid);
+    private native HashMap<String,String>[] nativeGetLocalizedSearchEngines(
+            int nativeTemplateUrlServiceAndroid);
+    private native void nativeSetSearchEngine(int nativeTemplateUrlServiceAndroid,
+            int selectedIndex);
+    private native int nativeGetSearchEngine(int nativeTemplateUrlServiceAndroid);
+}