core/java/android/webkit/WebIconDatabase.java - platform/frameworks/base - Git at Google

 /*
  * Copyright (C) 2006 The Android Open Source Project
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
  *
  *      http://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */

 package android.webkit;

 import android.content.ContentResolver;
 import android.database.Cursor;
 import android.graphics.Bitmap;
 import android.os.Handler;
 import android.os.Message;
 import android.provider.Browser;
 import android.util.Log;

 import java.util.HashMap;
 import java.util.Vector;

 /**
  * Functions for manipulating the icon database used by WebView.
  * These functions require that a WebView be constructed before being invoked
  * and WebView.getIconDatabase() will return a WebIconDatabase object. This
  * WebIconDatabase object is a single instance and all methods operate on that
  * single object.
  */
 public final class WebIconDatabase {
     private static final String LOGTAG = "WebIconDatabase";
     // Global instance of a WebIconDatabase
     private static WebIconDatabase sIconDatabase;
     // EventHandler for handling messages before and after the WebCore thread is
     // ready.
     private final EventHandler mEventHandler = new EventHandler();

     // Class to handle messages before WebCore is ready
     private static class EventHandler extends Handler {
         // Message ids
         static final int OPEN         = 0;
         static final int CLOSE        = 1;
         static final int REMOVE_ALL   = 2;
         static final int REQUEST_ICON = 3;
         static final int RETAIN_ICON  = 4;
         static final int RELEASE_ICON = 5;
         static final int BULK_REQUEST_ICON = 6;
         // Message for dispatching icon request results
         private static final int ICON_RESULT = 10;
         // Actual handler that runs in WebCore thread
         private Handler mHandler;
         // Vector of messages before the WebCore thread is ready
         private Vector<Message> mMessages = new Vector<Message>();
         // Class to handle a result dispatch
         private class IconResult {
             private final String mUrl;
             private final Bitmap mIcon;
             private final IconListener mListener;
             IconResult(String url, Bitmap icon, IconListener l) {
                 mUrl = url;
                 mIcon = icon;
                 mListener = l;
             }
             void dispatch() {
                 mListener.onReceivedIcon(mUrl, mIcon);
             }
         }

         @Override
         public void handleMessage(Message msg) {
             // Note: This is the message handler for the UI thread.
             switch (msg.what) {
                 case ICON_RESULT:
                     ((IconResult) msg.obj).dispatch();
                     break;
             }
         }

         // Called by WebCore thread to create the actual handler
         private synchronized void createHandler() {
             if (mHandler == null) {
                 mHandler = new Handler() {
                     @Override
                     public void handleMessage(Message msg) {
                         // Note: This is the message handler for the WebCore
                         // thread.
                         switch (msg.what) {
                             case OPEN:
                                 nativeOpen((String) msg.obj);
                                 break;

                             case CLOSE:
                                 nativeClose();
                                 break;

                             case REMOVE_ALL:
                                 nativeRemoveAllIcons();
                                 break;

                             case REQUEST_ICON:
                                 IconListener l = (IconListener) msg.obj;
                                 String url = msg.getData().getString("url");
                                 requestIconAndSendResult(url, l);
                                 break;

                             case BULK_REQUEST_ICON:
                                 bulkRequestIcons(msg);
                                 break;

                             case RETAIN_ICON:
                                 nativeRetainIconForPageUrl((String) msg.obj);
                                 break;

                             case RELEASE_ICON:
                                 nativeReleaseIconForPageUrl((String) msg.obj);
                                 break;
                         }
                     }
                 };
                 // Transfer all pending messages
                 for (int size = mMessages.size(); size > 0; size--) {
                     mHandler.sendMessage(mMessages.remove(0));
                 }
                 mMessages = null;
             }
         }

         private synchronized boolean hasHandler() {
             return mHandler != null;
         }

         private synchronized void postMessage(Message msg) {
             if (mMessages != null) {
                 mMessages.add(msg);
             } else {
                 mHandler.sendMessage(msg);
             }
         }

         private void bulkRequestIcons(Message msg) {
             HashMap map = (HashMap) msg.obj;
             IconListener listener = (IconListener) map.get("listener");
             ContentResolver cr = (ContentResolver) map.get("contentResolver");
             String where = (String) map.get("where");

             Cursor c = null;
             try {
                 c = cr.query(
                         Browser.BOOKMARKS_URI,
                         new String[] { Browser.BookmarkColumns.URL },
                         where, null, null);
                 if (c.moveToFirst()) {
                     do {
                         String url = c.getString(0);
                         requestIconAndSendResult(url, listener);
                     } while (c.moveToNext());
                 }
             } catch (IllegalStateException e) {
                 Log.e(LOGTAG, "BulkRequestIcons", e);
             } finally {
                 if (c != null) c.close();
             }
         }

         private void requestIconAndSendResult(String url, IconListener listener) {
             Bitmap icon = nativeIconForPageUrl(url);
             if (icon != null) {
                 sendMessage(obtainMessage(ICON_RESULT,
                             new IconResult(url, icon, listener)));
             }
         }
     }

     /**
      * Interface for receiving icons from the database.
      */
     public interface IconListener {
         /**
          * Called when the icon has been retrieved from the database and the
          * result is non-null.
          * @param url The url passed in the request.
          * @param icon The favicon for the given url.
          */
         public void onReceivedIcon(String url, Bitmap icon);
     }

     /**
      * Open a the icon database and store the icons in the given path.
      * @param path The directory path where the icon database will be stored.
      * @return True if the database was successfully opened or created in
      *         the given path.
      */
     public void open(String path) {
         if (path != null) {
             mEventHandler.postMessage(
                     Message.obtain(null, EventHandler.OPEN, path));
         }
     }

     /**
      * Close the shared instance of the icon database.
      */
     public void close() {
         mEventHandler.postMessage(
                 Message.obtain(null, EventHandler.CLOSE));
     }

     /**
      * Removes all the icons in the database.
      */
     public void removeAllIcons() {
         mEventHandler.postMessage(
                 Message.obtain(null, EventHandler.REMOVE_ALL));
     }

     /**
      * Request the Bitmap representing the icon for the given page
      * url. If the icon exists, the listener will be called with the result.
      * @param url The page's url.
      * @param listener An implementation on IconListener to receive the result.
      */
     public void requestIconForPageUrl(String url, IconListener listener) {
         if (listener == null || url == null) {
             return;
         }
         Message msg = Message.obtain(null, EventHandler.REQUEST_ICON, listener);
         msg.getData().putString("url", url);
         mEventHandler.postMessage(msg);
     }

     /** {@hide}
      */
     public void bulkRequestIconForPageUrl(ContentResolver cr, String where,
             IconListener listener) {
         if (listener == null) {
             return;
         }

         // Special case situation: we don't want to add this message to the
         // queue if there is no handler because we may never have a real
         // handler to service the messages and the cursor will never get
         // closed.
         if (mEventHandler.hasHandler()) {
             // Don't use Bundle as it is parcelable.
             HashMap<String, Object> map = new HashMap<String, Object>();
             map.put("contentResolver", cr);
             map.put("where", where);
             map.put("listener", listener);
             Message msg =
                     Message.obtain(null, EventHandler.BULK_REQUEST_ICON, map);
             mEventHandler.postMessage(msg);
         }
     }

     /**
      * Retain the icon for the given page url.
      * @param url The page's url.
      */
     public void retainIconForPageUrl(String url) {
         if (url != null) {
             mEventHandler.postMessage(
                     Message.obtain(null, EventHandler.RETAIN_ICON, url));
         }
     }

     /**
      * Release the icon for the given page url.
      * @param url The page's url.
      */
     public void releaseIconForPageUrl(String url) {
         if (url != null) {
             mEventHandler.postMessage(
                     Message.obtain(null, EventHandler.RELEASE_ICON, url));
         }
     }

     /**
      * Get the global instance of WebIconDatabase.
      * @return A single instance of WebIconDatabase. It will be the same
      *         instance for the current process each time this method is
      *         called.
      */
     public static WebIconDatabase getInstance() {
         // XXX: Must be created in the UI thread.
         if (sIconDatabase == null) {
             sIconDatabase = new WebIconDatabase();
         }
         return sIconDatabase;
     }

     /**
      * Create the internal handler and transfer all pending messages.
      * XXX: Called by WebCore thread only!
      */
     /*package*/ void createHandler() {
         mEventHandler.createHandler();
     }

     /**
      * Private constructor to avoid anyone else creating an instance.
      */
     private WebIconDatabase() {}

     // Native functions
     private static native void nativeOpen(String path);
     private static native void nativeClose();
     private static native void nativeRemoveAllIcons();
     private static native Bitmap nativeIconForPageUrl(String url);
     private static native void nativeRetainIconForPageUrl(String url);
     private static native void nativeReleaseIconForPageUrl(String url);
 }
	/*
	* Copyright (C) 2006 The Android Open Source Project
	*
	* Licensed under the Apache License, Version 2.0 (the "License");
	* you may not use this file except in compliance with the License.
	* You may obtain a copy of the License at
	*
	* http://www.apache.org/licenses/LICENSE-2.0
	*
	* Unless required by applicable law or agreed to in writing, software
	* distributed under the License is distributed on an "AS IS" BASIS,
	* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
	* See the License for the specific language governing permissions and
	* limitations under the License.
	*/

	package android.webkit;

	import android.content.ContentResolver;
	import android.database.Cursor;
	import android.graphics.Bitmap;
	import android.os.Handler;
	import android.os.Message;
	import android.provider.Browser;
	import android.util.Log;

	import java.util.HashMap;
	import java.util.Vector;

	/**
	* Functions for manipulating the icon database used by WebView.
	* These functions require that a WebView be constructed before being invoked
	* and WebView.getIconDatabase() will return a WebIconDatabase object. This
	* WebIconDatabase object is a single instance and all methods operate on that
	* single object.
	*/
	public final class WebIconDatabase {
	private static final String LOGTAG = "WebIconDatabase";
	// Global instance of a WebIconDatabase
	private static WebIconDatabase sIconDatabase;
	// EventHandler for handling messages before and after the WebCore thread is
	// ready.
	private final EventHandler mEventHandler = new EventHandler();

	// Class to handle messages before WebCore is ready
	private static class EventHandler extends Handler {
	// Message ids
	static final int OPEN = 0;
	static final int CLOSE = 1;
	static final int REMOVE_ALL = 2;
	static final int REQUEST_ICON = 3;
	static final int RETAIN_ICON = 4;
	static final int RELEASE_ICON = 5;
	static final int BULK_REQUEST_ICON = 6;
	// Message for dispatching icon request results
	private static final int ICON_RESULT = 10;
	// Actual handler that runs in WebCore thread
	private Handler mHandler;
	// Vector of messages before the WebCore thread is ready
	private Vector<Message> mMessages = new Vector<Message>();
	// Class to handle a result dispatch
	private class IconResult {
	private final String mUrl;
	private final Bitmap mIcon;
	private final IconListener mListener;
	IconResult(String url, Bitmap icon, IconListener l) {
	mUrl = url;
	mIcon = icon;
	mListener = l;
	}
	void dispatch() {
	mListener.onReceivedIcon(mUrl, mIcon);
	}
	}

	@Override
	public void handleMessage(Message msg) {
	// Note: This is the message handler for the UI thread.
	switch (msg.what) {
	case ICON_RESULT:
	((IconResult) msg.obj).dispatch();
	break;
	}
	}

	// Called by WebCore thread to create the actual handler
	private synchronized void createHandler() {
	if (mHandler == null) {
	mHandler = new Handler() {
	@Override
	public void handleMessage(Message msg) {
	// Note: This is the message handler for the WebCore
	// thread.
	switch (msg.what) {
	case OPEN:
	nativeOpen((String) msg.obj);
	break;

	case CLOSE:
	nativeClose();
	break;

	case REMOVE_ALL:
	nativeRemoveAllIcons();
	break;

	case REQUEST_ICON:
	IconListener l = (IconListener) msg.obj;
	String url = msg.getData().getString("url");
	requestIconAndSendResult(url, l);
	break;

	case BULK_REQUEST_ICON:
	bulkRequestIcons(msg);
	break;

	case RETAIN_ICON:
	nativeRetainIconForPageUrl((String) msg.obj);
	break;

	case RELEASE_ICON:
	nativeReleaseIconForPageUrl((String) msg.obj);
	break;
	}
	}
	};
	// Transfer all pending messages
	for (int size = mMessages.size(); size > 0; size--) {
	mHandler.sendMessage(mMessages.remove(0));
	}
	mMessages = null;
	}
	}

	private synchronized boolean hasHandler() {
	return mHandler != null;
	}

	private synchronized void postMessage(Message msg) {
	if (mMessages != null) {
	mMessages.add(msg);
	} else {
	mHandler.sendMessage(msg);
	}
	}

	private void bulkRequestIcons(Message msg) {
	HashMap map = (HashMap) msg.obj;
	IconListener listener = (IconListener) map.get("listener");
	ContentResolver cr = (ContentResolver) map.get("contentResolver");
	String where = (String) map.get("where");

	Cursor c = null;
	try {
	c = cr.query(
	Browser.BOOKMARKS_URI,
	new String[] { Browser.BookmarkColumns.URL },
	where, null, null);
	if (c.moveToFirst()) {
	do {
	String url = c.getString(0);
	requestIconAndSendResult(url, listener);
	} while (c.moveToNext());
	}
	} catch (IllegalStateException e) {
	Log.e(LOGTAG, "BulkRequestIcons", e);
	} finally {
	if (c != null) c.close();
	}
	}

	private void requestIconAndSendResult(String url, IconListener listener) {
	Bitmap icon = nativeIconForPageUrl(url);
	if (icon != null) {
	sendMessage(obtainMessage(ICON_RESULT,
	new IconResult(url, icon, listener)));
	}
	}
	}

	/**
	* Interface for receiving icons from the database.
	*/
	public interface IconListener {
	/**
	* Called when the icon has been retrieved from the database and the
	* result is non-null.
	* @param url The url passed in the request.
	* @param icon The favicon for the given url.
	*/
	public void onReceivedIcon(String url, Bitmap icon);
	}

	/**
	* Open a the icon database and store the icons in the given path.
	* @param path The directory path where the icon database will be stored.
	* @return True if the database was successfully opened or created in
	* the given path.
	*/
	public void open(String path) {
	if (path != null) {
	mEventHandler.postMessage(
	Message.obtain(null, EventHandler.OPEN, path));
	}
	}

	/**
	* Close the shared instance of the icon database.
	*/
	public void close() {
	mEventHandler.postMessage(
	Message.obtain(null, EventHandler.CLOSE));
	}

	/**
	* Removes all the icons in the database.
	*/
	public void removeAllIcons() {
	mEventHandler.postMessage(
	Message.obtain(null, EventHandler.REMOVE_ALL));
	}

	/**
	* Request the Bitmap representing the icon for the given page
	* url. If the icon exists, the listener will be called with the result.
	* @param url The page's url.
	* @param listener An implementation on IconListener to receive the result.
	*/
	public void requestIconForPageUrl(String url, IconListener listener) {
	if (listener == null \|\| url == null) {
	return;
	}
	Message msg = Message.obtain(null, EventHandler.REQUEST_ICON, listener);
	msg.getData().putString("url", url);
	mEventHandler.postMessage(msg);
	}

	/** {@hide}
	*/
	public void bulkRequestIconForPageUrl(ContentResolver cr, String where,
	IconListener listener) {
	if (listener == null) {
	return;
	}

	// Special case situation: we don't want to add this message to the
	// queue if there is no handler because we may never have a real
	// handler to service the messages and the cursor will never get
	// closed.
	if (mEventHandler.hasHandler()) {
	// Don't use Bundle as it is parcelable.
	HashMap<String, Object> map = new HashMap<String, Object>();
	map.put("contentResolver", cr);
	map.put("where", where);
	map.put("listener", listener);
	Message msg =
	Message.obtain(null, EventHandler.BULK_REQUEST_ICON, map);
	mEventHandler.postMessage(msg);
	}
	}

	/**
	* Retain the icon for the given page url.
	* @param url The page's url.
	*/
	public void retainIconForPageUrl(String url) {
	if (url != null) {
	mEventHandler.postMessage(
	Message.obtain(null, EventHandler.RETAIN_ICON, url));
	}
	}

	/**
	* Release the icon for the given page url.
	* @param url The page's url.
	*/
	public void releaseIconForPageUrl(String url) {
	if (url != null) {
	mEventHandler.postMessage(
	Message.obtain(null, EventHandler.RELEASE_ICON, url));
	}
	}

	/**
	* Get the global instance of WebIconDatabase.
	* @return A single instance of WebIconDatabase. It will be the same
	* instance for the current process each time this method is
	* called.
	*/
	public static WebIconDatabase getInstance() {
	// XXX: Must be created in the UI thread.
	if (sIconDatabase == null) {
	sIconDatabase = new WebIconDatabase();
	}
	return sIconDatabase;
	}

	/**
	* Create the internal handler and transfer all pending messages.
	* XXX: Called by WebCore thread only!
	*/
	/package/ void createHandler() {
	mEventHandler.createHandler();
	}

	/**
	* Private constructor to avoid anyone else creating an instance.
	*/
	private WebIconDatabase() {}

	// Native functions
	private static native void nativeOpen(String path);
	private static native void nativeClose();
	private static native void nativeRemoveAllIcons();
	private static native Bitmap nativeIconForPageUrl(String url);
	private static native void nativeRetainIconForPageUrl(String url);
	private static native void nativeReleaseIconForPageUrl(String url);
	}