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//----------- DBHelper -------------
package utility.db;
import java.io.FileNotFoundException;
import android.content.Context;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteDatabase.CursorFactory;
public class DBHelper
{
private SQLiteDatabase db = null;
private Context ctx = null;
public DBHelper( Context ctx )
{
this.ctx = ctx;
}
/**
* ÅжÏÊý¾Ý¿âÊÇ·ñ´æÔÚ
*
* @param dbName
* Êý¾Ý¿âÃû³Æ
* @return true´æÔÚ false²»´æÔÚ
*/
public boolean exist( String dbName )
{
Log.log("called fun : exist()");
boolean flag = false;
try
{
db = ctx.openDatabase(dbName, null);
Log.log("database/"+dbName+" exist");
flag = true;
}
catch (FileNotFoundException e)
{
flag = false;
Log.log("database/"+dbName+" not exist");
}
finally
{
if (db != null)
db.close();
db = null;
}
return flag;
}
/**
* ´ò¿ªÊý¾Ý¿â
*
* @param dbName
* Êý¾Ý¿âÃû³Æ
* @return true ´ò¿ª³É¹¦ false´ò¿ªÊ§°Ü
*/
public boolean openDatabase( String dbName , boolean created )
{
return openDatabase(dbName, null, created);
}
/**
* ´ò¿ªÊý¾Ý¿â
*
* @param dbName
* Êý¾Ý¿âÃû³Æ
* @param factory
* @return true ´ò¿ª³É¹¦ false´ò¿ªÊ§°Ü
*/
public boolean openDatabase( String dbName , CursorFactory factory ,
boolean created )
{
Log.log("called fun : openDatabase()");
Log.log("called fun : if not exist then created "+dbName+" ? : "+created);
boolean flag = false;
if(exist(dbName))
{
try
{
db = ctx.openDatabase(dbName, factory);
Log.log("database/"+dbName+" is opened");
flag = true;
}
catch (FileNotFoundException e)
{
Log.log("database/"+dbName+" is not opened");
flag = false;
}
}
else
{
if(created)
{
flag = createDatabase(dbName, 1, 0, factory);
}
else
{
flag = false;
}
}
return flag;
}