<?xml version="1.0"?>
<!DOCTYPE hibernate-mapping PUBLIC"-Hibernate/Hibernate Mapping DTD 3.0//EN//""http://hibernate.sourceforge.net/hibernate-mapping-3.0.dtd"><hibernate-mapping package="vaint.wyt.db"><class name="User" table="user"><id name="userId" column="user_id"><generator class="assigned"/></id><property name="name" type="string" length="25" /><property name="gender" type="string" length="10" /><property name="password" type="string" length="20"/><property name="photo" type="text" length="2147483647"/></class></hibernate-mapping>

public class DBHelper extends SQLiteOpenHelper{private static final int DATABASE_VERSION = 1;/**好友列表 表名*/public static final String FRIENDS = "friends";/**聊天列表 表名*/public static final String CHAT_LIST = "chat_list";/**好友请求 表名*/public static final String NEW_FRIENDS = "new_friends";/**聊天记录表名前缀*/public static final String CHATTING_PREFIX = "chatting_";/**@param userId 以当前用户ID作为数据库名称*/public DBHelper(Context context,String userId) {//CursorFactory设置为null,使用默认值super(context, userId, null, DATABASE_VERSION);}//数据库第一次被创建时onCreate会被调用@Overridepublic void onCreate(SQLiteDatabase db) {//好友列表db.execSQL("CREATE TABLE IF NOT EXISTS " + FRIENDS + " (friend_id VARCHAR(20) PRIMARY KEY, name VARCHAR(25), gender VARCHAR(10), photo TEXT)");//聊天列表db.execSQL("CREATE TABLE IF NOT EXISTS  " + CHAT_LIST + " (friend_id VARCHAR(20) PRIMARY KEY, unread INTEGER, content VARCHAR(20), time VARCHAR(10))");//好友请求列表db.execSQL("CREATE TABLE IF NOT EXISTS  " + NEW_FRIENDS + " (user_id VARCHAR(20) PRIMARY KEY, name VARCHAR(25), gender VARCHAR(10), verify_msg VARCHAR(20), time VARCHAR(10), is_agree INTEGER, photo TEXT)");}/**创建对应好友的聊天记录表，由于聊天记录表名需要根据好友ID来确定，所以只能在需要时新建*/public void createChattingTable(SQLiteDatabase db, String dbName){db.execSQL("CREATE TABLE IF NOT EXISTS " + dbName + " (id INTEGER PRIMARY KEY AUTOINCREMENT, time VARCHAR(10), msg TEXT, send INTEGER, show_time INTEGER)");}//如果DATABASE_VERSION值被修改,系统发现现有数据库版本不同,即会调用onUpgrade@Overridepublic void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {}}

2.增删改查（DBManager类）

public class DBManager {/** 获得聊天列表信息 */public List<ChatListModel> GetChatList() {List<ChatListModel> chatList = new ArrayList<ChatListModel>();// 查询所有聊天列表数据Cursor cursor = mSQLite.rawQuery("SELECT * FROM " + DBHelper.CHAT_LIST,null);while (cursor.moveToNext()) {ChatListModel model = new ChatListModel();// friend_id , unread , content , timeString friendId = cursor.getString(cursor.getColumnIndex("friend_id"));model.setFriendId(friendId);model.setContent(cursor.getString(cursor.getColumnIndex("content")));model.setTime(cursor.getString(cursor.getColumnIndex("time")));model.setUnread(cursor.getInt(cursor.getColumnIndex("unread")));//ChatListModel的title和photo需要从friends表中获取Cursor c = mSQLite.rawQuery("SELECT * FROM " + DBHelper.FRIENDS + " WHERE friend_id=?",   new String[]{friendId});if(c.moveToNext()){model.setTitle(c.getString(c.getColumnIndex("name")));model.setPhoto(c.getString(c.getColumnIndex("photo")));}chatList.add(model);}cursor.close();return chatList;}/** 更新聊天列表信息 覆盖更新 */public void UpdateChatList(List<ChatListModel> chatList) {ChatListModel model;// 开启事务mSQLite.beginTransaction();// 清空原来的聊天列表数据mSQLite.delete(DBHelper.CHAT_LIST, null, null);try {for (int i = 0; i < chatList.size(); i++) {model = chatList.get(i);// friend_id , unread , content , time mSQLite.execSQL("INSERT INTO " + DBHelper.CHAT_LIST + " VALUES(?, ?, ?, ?)",new Object[] { model.getFriendId(), model.getUnread(),model.getContent(), model.getTime()});}// 设置事务成功，不设置则回滚不提交mSQLite.setTransactionSuccessful();} finally {// 结束事务mSQLite.endTransaction();}}
}

public class CacheUtils {private static List<ChatListModel> chatList = null;/**缓存聊天列表*/public static void UpdateChatList(List<ChatListModel> list) {chatList = list;}/** 根据好友列表信息更新聊天会话信息。* 如头像和昵称<BR/>需要判断返回值是否为null，再进行本地化存储 */public static List<ChatListModel> UpdateChatList(FriendList friendList) {if(chatList == null)return null;for(int i=0;i<chatList.size();i++){ChatListModel model = chatList.get(i);String friendId = model.getFriendId();User user = friendList.getFriendsMap().get(friendId);if(user!=null){//更新数据model.setPhoto(user.getPhoto());model.setTitle(user.getName());//删除原数据chatList.remove(i);//插入新数据chatList.add(i, model);}}return chatList;}/**更新对应好友的聊天列表信息*/public static List<ChatListModel> UpdateChatList(String friendId, ChatListModel model){if(chatList == null)chatList = new ArrayList<ChatListModel>();int index = GetChatPosition(friendId);if(index != -1)//聊天会话已经存在{ChatListModel m = chatList.remove(index);//删除原记录//未读消息数目:原来+本次int unread = m.getUnread() + model.getUnread();model.setUnread(unread);}chatList.add(0, model);//添加到首位return chatList;}/*** 删除聊天列表中的对应会话<BR/>* @return 返回true，说明原来该好友的聊天会话存在，需要更新本地数据，以及删除对应聊天记录<BR/>* 否则无需更新其他数据*/public static boolean RemoveChat(String friendId){int index = GetChatPosition(friendId);if(index != -1)//聊天会话存在{chatList.remove(index);//删除原记录return true;}return false;}/**获得聊天列表*/public static List<ChatListModel> GetChatList(){return chatList;}/**根据好友ID，获得聊天会话在聊天列表的位置。-1表示会话不存在，需要新建*/private static int GetChatPosition(String friendId){if(chatList == null)return -1;for(int i=0; i<chatList.size(); i++){ChatListModel model = chatList.get(i);if(model.getFriendId().equals(friendId)){return i;}}return -1;}
}

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