Java tutorial
/* -*- Mode: Java; c-basic-offset: 4; tab-width: 20; indent-tabs-mode: nil; -*- * This Source Code Form is subject to the terms of the Mozilla Public * License, v. 2.0. If a copy of the MPL was not distributed with this * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ package org.mozilla.gecko.home; import java.util.EnumSet; import org.mozilla.gecko.GeckoProfile; import org.mozilla.gecko.Telemetry; import org.mozilla.gecko.db.BrowserDB.FilterFlags; import android.content.Context; import android.database.Cursor; import android.os.Bundle; import android.os.SystemClock; import android.support.v4.app.LoaderManager; import android.support.v4.app.LoaderManager.LoaderCallbacks; import android.support.v4.content.Loader; /** * Encapsulates the implementation of the search cursor loader. */ class SearchLoader { public static final String LOGTAG = "GeckoSearchLoader"; private static final String KEY_SEARCH_TERM = "search_term"; private static final String KEY_FILTER_FLAGS = "flags"; private SearchLoader() { } @SuppressWarnings("unchecked") public static Loader<Cursor> createInstance(Context context, Bundle args) { if (args != null) { final String searchTerm = args.getString(KEY_SEARCH_TERM); final EnumSet<FilterFlags> flags = (EnumSet<FilterFlags>) args.getSerializable(KEY_FILTER_FLAGS); return new SearchCursorLoader(context, searchTerm, flags); } else { return new SearchCursorLoader(context, "", EnumSet.noneOf(FilterFlags.class)); } } private static Bundle createArgs(String searchTerm, EnumSet<FilterFlags> flags) { Bundle args = new Bundle(); args.putString(SearchLoader.KEY_SEARCH_TERM, searchTerm); args.putSerializable(SearchLoader.KEY_FILTER_FLAGS, flags); return args; } public static void init(LoaderManager manager, int loaderId, LoaderCallbacks<Cursor> callbacks, String searchTerm) { init(manager, loaderId, callbacks, searchTerm, EnumSet.noneOf(FilterFlags.class)); } public static void init(LoaderManager manager, int loaderId, LoaderCallbacks<Cursor> callbacks, String searchTerm, EnumSet<FilterFlags> flags) { final Bundle args = createArgs(searchTerm, flags); manager.initLoader(loaderId, args, callbacks); } public static void restart(LoaderManager manager, int loaderId, LoaderCallbacks<Cursor> callbacks, String searchTerm) { restart(manager, loaderId, callbacks, searchTerm, EnumSet.noneOf(FilterFlags.class)); } public static void restart(LoaderManager manager, int loaderId, LoaderCallbacks<Cursor> callbacks, String searchTerm, EnumSet<FilterFlags> flags) { final Bundle args = createArgs(searchTerm, flags); manager.restartLoader(loaderId, args, callbacks); } public static class SearchCursorLoader extends SimpleCursorLoader { private static final String TELEMETRY_HISTOGRAM_LOAD_CURSOR = "FENNEC_SEARCH_LOADER_TIME_MS"; // Max number of search results. private static final int SEARCH_LIMIT = 100; // The target search term associated with the loader. private final String mSearchTerm; // The filter flags associated with the loader. private final EnumSet<FilterFlags> mFlags; private final GeckoProfile mProfile; public SearchCursorLoader(Context context, String searchTerm, EnumSet<FilterFlags> flags) { super(context); mSearchTerm = searchTerm; mFlags = flags; mProfile = GeckoProfile.get(context); } @Override public Cursor loadCursor() { final long start = SystemClock.uptimeMillis(); final Cursor cursor = mProfile.getDB().filter(getContext().getContentResolver(), mSearchTerm, SEARCH_LIMIT, mFlags); final long end = SystemClock.uptimeMillis(); final long took = end - start; Telemetry.addToHistogram(TELEMETRY_HISTOGRAM_LOAD_CURSOR, (int) Math.min(took, Integer.MAX_VALUE)); return cursor; } public String getSearchTerm() { return mSearchTerm; } } }