Android源码目录packages\providers下的应用是下载,通话等内置基本应用提供数据存储和操作的provider应用,本文章将针对ContactsProvider源码的架构和实现展开分SEO靠我析。(注:本文使用使用android4.0版本进行分析)
1、架构设计
ContactsProvider中数据操作基类是AbstractContactsProvider.java(参见frameworksSEO靠我\ex\common\java\com\android\common\content\SQLiteContentProvider.java),它继承ContentProvider.java实现SQLiSEO靠我teTransactionListener.java,类结构如下图所示:
图 1 provider结构图
该类是抽象基类,在里面实现了父类的insert、delete和update三个抽象方法,在这三个方SEO靠我法中在其中使用了事务对数据库进行操作。该类设计时,使用了模板模式模板方法为insertInTransaction,updateInTransaction和deleteInTransaction。该类在SEO靠我对数据库进行事务操作的同时,对子类开放了onRollback,onCommit等事物回调方法,子类可以根据自己的业务特点进行扩展。增删改查的调用过程如下图2 3 4所示:
图2 插入操作
图 3 更新操SEO靠我作
图 4 删除操作
在整个设计中有两个类继承了AbstractContactsProvider.java,一个是ContactsProvider2.java,我们在调用系统的联系人数据时基本都是调用该类SEO靠我,里面封装了所有联系人的数据操作。第二个是ProfileProvider.java,该类是ContactsProvider2.java的委托类。这三个类的类间关系如下图5所示:
图 5 类间关系图
类CoSEO靠我ntactsTransaction.java是对事务的管理类,主要对进行的事务进行管理,类似一个事务池。是AbstractContactsProvider.java中事务处理的核心类。
DataRowHSEO靠我andler.java是数据处理抽象类,实现了对数据的增删改操作,子类有如下几个:
[java]view plain copy DataRowHandlerForCommonDataKind.java SEO靠我 DataRowHandlerForCustomMimetype.java DataRowHandlerForEmail.java DataRowHandlerForGroupMembersSEO靠我hip.java DataRowHandlerForIm.java DataRowHandlerForNickname.java DataRowHandlerForNote.java SEO靠我DataRowHandlerForOrganization.java DataRowHandlerForPhoneNumber.java DataRowHandlerForPhoto.javaSEO靠我 DataRowHandlerForStructuredName.java DataRowHandlerForStructuredPostal.java这些子类在ContactsProvideSEO靠我r2#initDataRowHandlers中初始化
[java]view plain copy private void initDataRowHandlers(Map<String, DataRowSEO靠我Handler> handlerMap, ContactsDatabaseHelper dbHelper, ContactAggregator contactAggregator,SEO靠我 PhotoStore photoStore) { Context context = getContext(); handlerMap.put(EmailSEO靠我.CONTENT_ITEM_TYPE, new DataRowHandlerForEmail(context, dbHelper, contactAggregator));SEO靠我 handlerMap.put(Im.CONTENT_ITEM_TYPE, new DataRowHandlerForIm(context, dbHelper,SEO靠我 contactAggregator)); handlerMap.put(Organization.CONTENT_ITEM_TYPE, new DataRowSEO靠我HandlerForOrganization(context, dbHelper, contactAggregator)); handlerMap.put(Phone.CONTENT_ITSEO靠我EM_TYPE, new DataRowHandlerForPhoneNumber(context, dbHelper, contactAggregator)); SEO靠我 handlerMap.put(Nickname.CONTENT_ITEM_TYPE, new DataRowHandlerForNickname(context, dbSEO靠我Helper, contactAggregator)); handlerMap.put(StructuredName.CONTENT_ITEM_TYPE, neSEO靠我w DataRowHandlerForStructuredName(context, dbHelper, contactAggregator, mNameSSEO靠我plitter, mNameLookupBuilder)); handlerMap.put(StructuredPostal.CONTENT_ITEM_TYPE, SEO靠我 new DataRowHandlerForStructuredPostal(context, dbHelper, contactAggregator, SEO靠我mPostalSplitter)); handlerMap.put(GroupMembership.CONTENT_ITEM_TYPE, new DataRowSEO靠我HandlerForGroupMembership(context, dbHelper, contactAggregator, mGroupIdCache)SEO靠我); handlerMap.put(Photo.CONTENT_ITEM_TYPE, new DataRowHandlerForPhoto(context, dSEO靠我bHelper, contactAggregator, photoStore)); handlerMap.put(Note.CONTENT_ITEM_TYPE, SEO靠我 new DataRowHandlerForNote(context, dbHelper, contactAggregator)); }这些子类在getDataRowHandler方法中中通过miSEO靠我metype进行调用:
[java]view plain copy public DataRowHandler getDataRowHandler(final String mimeType) { SEO靠我 if (inProfileMode()) { return getDataRowHandlerForProfile(mimeType); } DatSEO靠我aRowHandler handler = mDataRowHandlers.get(mimeType); if (handler == null) { handlerSEO靠我 = new DataRowHandlerForCustomMimetype( getContext(), mContactsHelper, mContactAggSEO靠我regator, mimeType); mDataRowHandlers.put(mimeType, handler); } return handler;SEO靠我 }getDataRowHandler方法在insertData,deleteData和updateData方法中被调用。
[java]view plain copy /** * InseSEO靠我rts an item in the data table * * @param values the values for the new row * @return SEO靠我the row ID of the newly created row */ private long insertData(ContentValues values, booleSEO靠我an callerIsSyncAdapter) { long id = 0; mValues.clear(); mValues.putAll(vaSEO靠我lues); long rawContactId = mValues.getAsLong(Data.RAW_CONTACT_ID); // Replace packSEO靠我age with internal mapping final String packageName = mValues.getAsString(Data.RES_PACKAGE);SEO靠我 if (packageName != null) { mValues.put(DataColumns.PACKAGE_ID, mDbHelper.get(SEO靠我).getPackageId(packageName)); } mValues.remove(Data.RES_PACKAGE); // ReplSEO靠我ace mimetype with internal mapping final String mimeType = mValues.getAsString(Data.MIMETYPSEO靠我E); if (TextUtils.isEmpty(mimeType)) { throw new IllegalArgumentException(DataSEO靠我.MIMETYPE + " is required"); } mValues.put(DataColumns.MIMETYPE_ID, mDbHelper.get(SEO靠我).getMimeTypeId(mimeType)); mValues.remove(Data.MIMETYPE); DataRowHandler rowHandlSEO靠我er = <span style="color: rgb(102, 102, 204);">getDataRowHandler(mimeType)</span>; id = rowHSEO靠我andler.insert(mActiveDb.get(), mTransactionContext.get(), rawContactId, mValues); if (!callSEO靠我erIsSyncAdapter) { mTransactionContext.get().markRawContactDirty(rawContactId); SEO靠我 } mTransactionContext.get().rawContactUpdated(rawContactId); return id; }所有SEO靠我数据的mimetype都被存储在表Tables.MIMETYPES中,该只有两个字段_id和mimetype。
[java]view plain copy db.execSQL("CREATE TABLSEO靠我E " + Tables.MIMETYPES + " (" + MimetypesColumns._ID + " INTEGER PRIMARY KEY AUTOINCSEO靠我REMENT," + MimetypesColumns.MIMETYPE + " TEXT NOT NULL" + ");");Tables.MIMETYPES表数据的SEO靠我存储是在ContactsDatabaseHelper#lookupAndCacheId中进行的,具体调用过程如下图 6 所示:
图 6 mimetype数据调用流程图
2、表结构
ContactsProviSEO靠我der 中共创建了25张表,
[java]view plain copy public static final String CONTACTS = "contacts"; public statiSEO靠我c final String RAW_CONTACTS = "raw_contacts"; public static final String STREAM_ITEMS = "stream_itSEO靠我ems"; public static final String STREAM_ITEM_PHOTOS = "stream_item_photos"; public static final SEO靠我String PHOTO_FILES = "photo_files"; public static final String PACKAGES = "packages"; public staSEO靠我tic final String MIMETYPES = "mimetypes"; public static final String PHONE_LOOKUP = "phone_lookup"SEO靠我; public static final String NAME_LOOKUP = "name_lookup"; public static final String AGGREGATIONSEO靠我_EXCEPTIONS = "agg_exceptions"; public static final String SETTINGS = "settings"; public static SEO靠我final String DATA = "data"; public static final String GROUPS = "groups"; public static final StSEO靠我ring PRESENCE = "presence"; public static final String AGGREGATED_PRESENCE = "agg_presence"; pubSEO靠我lic static final String NICKNAME_LOOKUP = "nickname_lookup"; public static final String CALLS = "cSEO靠我alls"; public static final String STATUS_UPDATES = "status_updates"; public static final String SEO靠我PROPERTIES = "properties"; public static final String ACCOUNTS = "accounts"; public static finalSEO靠我 String VISIBLE_CONTACTS = "visible_contacts"; public static final String DIRECTORIES = "directoriSEO靠我es"; public static final String DEFAULT_DIRECTORY = "default_directory"; public static final StrSEO靠我ing SEARCH_INDEX = "search_index"; public static final String VOICEMAIL_STATUS = "voicemail_statusSEO靠我";
这些表数据对开发者开放的api在 \frameworks\base\core\java\android\provider\文件夹下, [java]view plain copy CallLog.jaSEO靠我va Contacts.java ContactsContract.java SocialContract.java SyncConstValue.java VoicemailCoSEO靠我ntract.java由于数据查询涉及多个表间关系,大量数据的查询都是通过视图来完成的,创建了如下8个视图,而这几个视图是大家在调用api进行查询时显示的数据:
[java]view plain copSEO靠我y public interface Views { public static final String DATA = "view_data"; public static SEO靠我final String RAW_CONTACTS = "view_raw_contacts"; public static final String CONTACTS = "view_cSEO靠我ontacts"; public static final String ENTITIES = "view_entities"; public static final StrSEO靠我ing RAW_ENTITIES = "view_raw_entities"; public static final String GROUPS = "view_groups"; SEO靠我 public static final String DATA_USAGE_STAT = "view_data_usage_stat"; public static final StSEO靠我ring STREAM_ITEMS = "view_stream_items"; }4、总结
ContactsProvder是provider源码中数据处理和架构比较全面的一个应用,可以将它的架构核SEO靠我心抽离出来供大家参考和借鉴,以下类构成了整个架构的核心类,可以重点研究:
[java]view plain copy AbstractContactsProvider.java ContactAggSEO靠我regator.java ContactsDatabaseHelper.java ContactsProvider2.java ContactsTransaction.java TraSEO靠我nsactionContext.java网站备案号:浙ICP备17034767号-2