Here is the one more problem which i m facing this time the runnin time error am getting is Failed To open the database.. please look at my logcat file and suggest me the solution .
这是错误 m 得到“无法打开数据库'/data/data/com.example.crudoperation/myDB'。12-03 13:24:33.651: E/SQLiteDatabase(798): android.database.sqlite.SQLiteCantOpenDatabaseException:未知错误（代码 14）：无法打开”。请查看 DataBaseManager 类中的代码，并为我找到一些解决方法。我已经完美地运行了此代码。但是我尝试将此代码嵌入到其他一些项目中，但在这里我得到了这个错误。
数据库管理器.java
package com.example.crudoperation;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import android.content.ContentValues;
import android.content.Context;
import android.database.Cursor;
import android.database.SQLException;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteException;
import android.database.sqlite.SQLiteOpenHelper;
public class DBAdapter extends SQLiteOpenHelper{
//The Android's default system path of your application database.
private static String DB_PATH = "/data/data/com.example.crudoperation/";
private static String DB_NAME = "myDB";
private SQLiteDatabase myDataBase;
private final Context myContext;
private static String DB_IN = "firstdb";
public static final String KEY_ROWID = "_id";
public static final String KEY_NAME = "name";
public static final String KEY_EMAIL = "email";
private static final String DATABASE_TABLE = "Contact";
/**
* Constructor
* Takes and keeps a reference of the passed context in order to access to the application assets and resources.
* @param context
*/
public DBAdapter(Context context) {
super(context, DB_NAME, null, 1);
this.myContext = context;
}
/**
* Creates a empty database on the system and rewrites it with your own database.
* */
public void createDataBase() throws IOException{
boolean dbExist = checkDataBase();
if(dbExist){
//do nothing - database already exist
}else{
//By calling this method and empty database will be created into the default system path
//of your application so we are gonna be able to overwrite that database with our database.
this.getReadableDatabase();
try {
copyDataBase();
} catch (IOException e) {
throw new Error("Error copying database");
}
}
}
/**
* Check if the database already exist to avoid re-copying the file each time you open the application.
* @return true if it exists, false if it doesn't
*/
private boolean checkDataBase(){
SQLiteDatabase checkDB = null;
try{
String myPath = DB_PATH + DB_NAME;
checkDB = SQLiteDatabase.openDatabase(myPath, null, SQLiteDatabase.OPEN_READONLY);
}catch(SQLiteException e){
//database does't exist yet.
}
if(checkDB != null){
checkDB.close();
}
return checkDB != null ? true : false;
}
/**
* Copies your database from your local assets-folder to the just created empty database in the
* system folder, from where it can be accessed and handled.
* This is done by transfering bytestream.
* */
private void copyDataBase() throws IOException{
//Open your local db as the input stream
InputStream myInput = myContext.getAssets().open(DB_IN);
// Path to the just created empty db
String outFileName = DB_PATH + DB_NAME;
//Open the empty db as the output stream
OutputStream myOutput = new FileOutputStream(outFileName);
//transfer bytes from the inputfile to the outputfile
byte[] buffer = new byte[1024];
int length;
while ((length = myInput.read(buffer))>0){
myOutput.write(buffer, 0, length);
}
//Close the streams
myOutput.flush();
myOutput.close();
myInput.close();
}
public void openDataBase() throws SQLException{
//Open the database
String myPath = DB_PATH + DB_NAME;
myDataBase = SQLiteDatabase.openDatabase(myPath, null, SQLiteDatabase.OPEN_READWRITE);
}
@Override
public synchronized void close() {
if(myDataBase != null)
myDataBase.close();
super.close();
}
//---insert a contact into the database---
public long insertContact(String name, String email)
{
ContentValues initialValues = new ContentValues();
initialValues.put(KEY_NAME, name);
initialValues.put(KEY_EMAIL, email);
return myDataBase.insert(DATABASE_TABLE, null, initialValues);
}
//---updates a contact---
public boolean updateContact(long rowId, String name, String email)
{
ContentValues args = new ContentValues();
args.put(KEY_NAME, name);
args.put(KEY_EMAIL, email);
return myDataBase.update(DATABASE_TABLE, args, KEY_ROWID + "=" + rowId, null) > 0;
}
//---deletes a particular contact---
public boolean deleteContact(long rowId)
{
return myDataBase.delete(DATABASE_TABLE, KEY_ROWID + "=" + rowId, null) > 0;
}
//----Retrieving all Contacts From Database ------
public Cursor getAllContacts()
{
return myDataBase.query(DATABASE_TABLE, new String[] {KEY_ROWID, KEY_NAME,
KEY_EMAIL}, null, null, null, null, null);
}
@Override
public void onCreate(SQLiteDatabase db) {
}
@Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
}
// Add your public helper methods to access and get content from the database.
// You could return cursors by doing "return myDataBase.query(....)" so it'd be easy
// to you to create adapters for your views.
}
LogCat:
12-03 13:24:33.623: E/SQLiteLog(798): (14) cannot open file at line 30174 of [00bb9c9ce4]
12-03 13:24:33.623: E/SQLiteLog(798): (14) os_unix.c:30174: (2) open(/data/data/com.example.crudoperation/myDB) -
12-03 13:24:33.651: E/SQLiteDatabase(798): Failed to open database '/data/data/com.example.crudoperation/myDB'.
12-03 13:24:33.651: E/SQLiteDatabase(798): android.database.sqlite.SQLiteCantOpenDatabaseException: unknown error (code 14): Could not open database
12-03 13:24:33.651: E/SQLiteDatabase(798): at android.database.sqlite.SQLiteConnection.nativeOpen(Native Method)
12-03 13:24:33.651: E/SQLiteDatabase(798): at android.database.sqlite.SQLiteConnection.open(SQLiteConnection.java:209)
12-03 13:24:33.651: E/SQLiteDatabase(798): at android.database.sqlite.SQLiteConnection.open(SQLiteConnection.java:193)
12-03 13:24:33.651: E/SQLiteDatabase(798): at android.database.sqlite.SQLiteConnectionPool.openConnectionLocked(SQLiteConnectionPool.java:463)
12-03 13:24:33.651: E/SQLiteDatabase(798): at android.database.sqlite.SQLiteConnectionPool.open(SQLiteConnectionPool.java:185)
12-03 13:24:33.651: E/SQLiteDatabase(798): at android.database.sqlite.SQLiteConnectionPool.open(SQLiteConnectionPool.java:177)
12-03 13:24:33.651: E/SQLiteDatabase(798): at android.database.sqlite.SQLiteDatabase.openInner(SQLiteDatabase.java:804)
12-03 13:24:33.651: E/SQLiteDatabase(798): at android.database.sqlite.SQLiteDatabase.open(SQLiteDatabase.java:789)
12-03 13:24:33.651: E/SQLiteDatabase(798): at android.database.sqlite.SQLiteDatabase.openDatabase(SQLiteDatabase.java:694)
12-03 13:24:33.651: E/SQLiteDatabase(798): at android.database.sqlite.SQLiteDatabase.openDatabase(SQLiteDatabase.java:669)
12-03 13:24:33.651: E/SQLiteDatabase(798): at com.example.crudoperation.DBAdapter.openDataBase(DBAdapter.java:109)
12-03 13:24:33.651: E/SQLiteDatabase(798): at com.example.crudoperation.InsertActivity.insertRecord(InsertActivity.java:70)
12-03 13:24:33.651: E/SQLiteDatabase(798): at com.example.crudoperation.InsertActivity$1.onClick(InsertActivity.java:52)
12-03 13:24:33.651: E/SQLiteDatabase(798): at android.view.View.performClick(View.java:4084)
12-03 13:24:33.651: E/SQLiteDatabase(798): at android.view.View$PerformClick.run(View.java:16966)
12-03 13:24:33.651: E/SQLiteDatabase(798): at android.os.Handler.handleCallback(Handler.java:615)
12-03 13:24:33.651: E/SQLiteDatabase(798): at android.os.Handler.dispatchMessage(Handler.java:92)
12-03 13:24:33.651: E/SQLiteDatabase(798): at android.os.Looper.loop(Looper.java:137)
12-03 13:24:33.651: E/SQLiteDatabase(798): at android.app.ActivityThread.main(ActivityThread.java:4745)
12-03 13:24:33.651: E/SQLiteDatabase(798): at java.lang.reflect.Method.invokeNative(Native Method)
12-03 13:24:33.651: E/SQLiteDatabase(798): at java.lang.reflect.Method.invoke(Method.java:511)
12-03 13:24:33.651: E/SQLiteDatabase(798): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:786)
12-03 13:24:33.651: E/SQLiteDatabase(798): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:553)
12-03 13:24:33.651: E/SQLiteDatabase(798): at dalvik.system.NativeStart.main(Native Method)
12-03 13:24:33.651: D/AndroidRuntime(798): Shutting down VM
12-03 13:24:33.661: W/dalvikvm(798): threadid=1: thread exiting with uncaught exception (group=0x40a13300)
12-03 13:24:33.692: E/AndroidRuntime(798): FATAL EXCEPTION: main
12-03 13:24:33.692: E/AndroidRuntime(798): android.database.sqlite.SQLiteCantOpenDatabaseException: unknown error (code 14): Could not open database
12-03 13:24:33.692: E/AndroidRuntime(798): at android.database.sqlite.SQLiteConnection.nativeOpen(Native Method)
12-03 13:24:33.692: E/AndroidRuntime(798): at android.database.sqlite.SQLiteConnection.open(SQLiteConnection.java:209)
12-03 13:24:33.692: E/AndroidRuntime(798): at android.database.sqlite.SQLiteConnection.open(SQLiteConnection.java:193)
12-03 13:24:33.692: E/AndroidRuntime(798): at android.database.sqlite.SQLiteConnectionPool.openConnectionLocked(SQLiteConnectionPool.java:463)
12-03 13:24:33.692: E/AndroidRuntime(798): at android.database.sqlite.SQLiteConnectionPool.open(SQLiteConnectionPool.java:185)
12-03 13:24:33.692: E/AndroidRuntime(798): at android.database.sqlite.SQLiteConnectionPool.open(SQLiteConnectionPool.java:177)
12-03 13:24:33.692: E/AndroidRuntime(798): at android.database.sqlite.SQLiteDatabase.openInner(SQLiteDatabase.java:804)
12-03 13:24:33.692: E/AndroidRuntime(798): at android.database.sqlite.SQLiteDatabase.open(SQLiteDatabase.java:789)
12-03 13:24:33.692: E/AndroidRuntime(798): at android.database.sqlite.SQLiteDatabase.openDatabase(SQLiteDatabase.java:694)
12-03 13:24:33.692: E/AndroidRuntime(798): at android.database.sqlite.SQLiteDatabase.openDatabase(SQLiteDatabase.java:669)
12-03 13:24:33.692: E/AndroidRuntime(798): at com.example.crudoperation.DBAdapter.openDataBase(DBAdapter.java:109)
12-03 13:24:33.692: E/AndroidRuntime(798): at com.example.crudoperation.InsertActivity.insertRecord(InsertActivity.java:70)
12-03 13:24:33.692: E/AndroidRuntime(798): at com.example.crudoperation.InsertActivity$1.onClick(InsertActivity.java:52)
12-03 13:24:33.692: E/AndroidRuntime(798): at android.view.View.performClick(View.java:4084)
12-03 13:24:33.692: E/AndroidRuntime(798): at android.view.View$PerformClick.run(View.java:16966)
12-03 13:24:33.692: E/AndroidRuntime(798): at android.os.Handler.handleCallback(Handler.java:615)
12-03 13:24:33.692: E/AndroidRuntime(798): at android.os.Handler.dispatchMessage(Handler.java:92)
12-03 13:24:33.692: E/AndroidRuntime(798): at android.os.Looper.loop(Looper.java:137)
12-03 13:24:33.692: E/AndroidRuntime(798): at android.app.ActivityThread.main(ActivityThread.java:4745)
12-03 13:24:33.692: E/AndroidRuntime(798): at java.lang.reflect.Method.invokeNative(Native Method)
12-03 13:24:33.692: E/AndroidRuntime(798): at java.lang.reflect.Method.invoke(Method.java:511)
12-03 13:24:33.692: E/AndroidRuntime(798): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:786)
12-03 13:24:33.692: E/AndroidRuntime(798): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:553)
12-03 13:24:33.692: E/AndroidRuntime(798): at dalvik.system.NativeStart.main(Native Method)