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/*
* Copyright 2013 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package com.example.android.basicsyncadapter.provider;
import android.content.ContentProvider;
import android.content.ContentValues;
import android.content.Context;
import android.content.UriMatcher;
import android.database.Cursor;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteOpenHelper;
import android.net.Uri;
import com.example.android.common.db.SelectionBuilder;
public class FeedProvider extends ContentProvider {
FeedDatabase mDatabaseHelper;
/**
* Content authority for this provider.
*/
private static final String AUTHORITY = FeedContract.CONTENT_AUTHORITY;
// The constants below represent individual URI routes, as IDs. Every URI pattern recognized by
// this ContentProvider is defined using sUriMatcher.addURI(), and associated with one of these
// IDs.
//
// When a incoming URI is run through sUriMatcher, it will be tested against the defined
// URI patterns, and the corresponding route ID will be returned.
/**
* URI ID for route: /entries
*/
public static final int ROUTE_ENTRIES = 1;
/**
* URI ID for route: /entries/{ID}
*/
public static final int ROUTE_ENTRIES_ID = 2;
/**
* UriMatcher, used to decode incoming URIs.
*/
private static final UriMatcher sUriMatcher = new UriMatcher(UriMatcher.NO_MATCH);
static {
sUriMatcher.addURI(AUTHORITY, "entries", ROUTE_ENTRIES);
sUriMatcher.addURI(AUTHORITY, "entries/*", ROUTE_ENTRIES_ID);
}
@Override
public boolean onCreate() {
mDatabaseHelper = new FeedDatabase(getContext());
return true;
}
/**
* Determine the mime type for entries returned by a given URI.
*/
@Override
public String getType(Uri uri) {
final int match = sUriMatcher.match(uri);
switch (match) {
case ROUTE_ENTRIES:
return FeedContract.Entry.CONTENT_TYPE;
case ROUTE_ENTRIES_ID:
return FeedContract.Entry.CONTENT_ITEM_TYPE;
default:
throw new UnsupportedOperationException("Unknown uri: " + uri);
}
}
/**
* Perform a database query by URI.
*
* <p>Currently supports returning all entries (/entries) and individual entries by ID
* (/entries/{ID}).
*/
@Override
public Cursor query(Uri uri, String[] projection, String selection, String[] selectionArgs,
String sortOrder) {
SQLiteDatabase db = mDatabaseHelper.getReadableDatabase();
SelectionBuilder builder = new SelectionBuilder();
int uriMatch = sUriMatcher.match(uri);
switch (uriMatch) {
case ROUTE_ENTRIES_ID:
// Return a single entry, by ID.
String id = uri.getLastPathSegment();
builder.where(FeedContract.Entry._ID + "=?", id);
case ROUTE_ENTRIES:
// Return all known entries.
builder.table(FeedContract.Entry.TABLE_NAME)
.where(selection, selectionArgs);
Cursor c = builder.query(db, projection, sortOrder);
// Note: Notification URI must be manually set here for loaders to correctly
// register ContentObservers.
Context ctx = getContext();
assert ctx != null;
c.setNotificationUri(ctx.getContentResolver(), uri);
return c;
default:
throw new UnsupportedOperationException("Unknown uri: " + uri);
}
}
/**
* Insert a new entry into the database.
*/
@Override
public Uri insert(Uri uri, ContentValues values) {
final SQLiteDatabase db = mDatabaseHelper.getWritableDatabase();
assert db != null;
final int match = sUriMatcher.match(uri);
Uri result;
switch (match) {
case ROUTE_ENTRIES:
long id = db.insertOrThrow(FeedContract.Entry.TABLE_NAME, null, values);
result = Uri.parse(FeedContract.Entry.CONTENT_URI + "/" + id);
break;
case ROUTE_ENTRIES_ID:
throw new UnsupportedOperationException("Insert not supported on URI: " + uri);
default:
throw new UnsupportedOperationException("Unknown uri: " + uri);
}
// Send broadcast to registered ContentObservers, to refresh UI.
Context ctx = getContext();
assert ctx != null;
ctx.getContentResolver().notifyChange(uri, null, false);
return result;
}
/**
* Delete an entry by database by URI.
*/
@Override
public int delete(Uri uri, String selection, String[] selectionArgs) {
SelectionBuilder builder = new SelectionBuilder();
final SQLiteDatabase db = mDatabaseHelper.getWritableDatabase();
final int match = sUriMatcher.match(uri);
int count;
switch (match) {
case ROUTE_ENTRIES:
count = builder.table(FeedContract.Entry.TABLE_NAME)
.where(selection, selectionArgs)
.delete(db);
break;
case ROUTE_ENTRIES_ID:
String id = uri.getLastPathSegment();
count = builder.table(FeedContract.Entry.TABLE_NAME)
.where(FeedContract.Entry._ID + "=?", id)
.where(selection, selectionArgs)
.delete(db);
break;
default:
throw new UnsupportedOperationException("Unknown uri: " + uri);
}
// Send broadcast to registered ContentObservers, to refresh UI.
Context ctx = getContext();
assert ctx != null;
ctx.getContentResolver().notifyChange(uri, null, false);
return count;
}
/**
* Update an etry in the database by URI.
*/
@Override
public int update(Uri uri, ContentValues values, String selection, String[] selectionArgs) {
SelectionBuilder builder = new SelectionBuilder();
final SQLiteDatabase db = mDatabaseHelper.getWritableDatabase();
final int match = sUriMatcher.match(uri);
int count;
switch (match) {
case ROUTE_ENTRIES:
count = builder.table(FeedContract.Entry.TABLE_NAME)
.where(selection, selectionArgs)
.update(db, values);
break;
case ROUTE_ENTRIES_ID:
String id = uri.getLastPathSegment();
count = builder.table(FeedContract.Entry.TABLE_NAME)
.where(FeedContract.Entry._ID + "=?", id)
.where(selection, selectionArgs)
.update(db, values);
break;
default:
throw new UnsupportedOperationException("Unknown uri: " + uri);
}
Context ctx = getContext();
assert ctx != null;
ctx.getContentResolver().notifyChange(uri, null, false);
return count;
}
/**
* SQLite backend for @{link FeedProvider}.
*
* Provides access to an disk-backed, SQLite datastore which is utilized by FeedProvider. This
* database should never be accessed by other parts of the application directly.
*/
static class FeedDatabase extends SQLiteOpenHelper {
/** Schema version. */
public static final int DATABASE_VERSION = 1;
/** Filename for SQLite file. */
public static final String DATABASE_NAME = "feed.db";
private static final String TYPE_TEXT = " TEXT";
private static final String TYPE_INTEGER = " INTEGER";
private static final String COMMA_SEP = ",";
/** SQL statement to create "entry" table. */
private static final String SQL_CREATE_ENTRIES =
"CREATE TABLE " + FeedContract.Entry.TABLE_NAME + " (" +
FeedContract.Entry._ID + " INTEGER PRIMARY KEY," +
FeedContract.Entry.COLUMN_NAME_ENTRY_ID + TYPE_TEXT + COMMA_SEP +
FeedContract.Entry.COLUMN_NAME_TITLE + TYPE_TEXT + COMMA_SEP +
FeedContract.Entry.COLUMN_NAME_LINK + TYPE_TEXT + COMMA_SEP +
FeedContract.Entry.COLUMN_NAME_PUBLISHED + TYPE_INTEGER + ")";
/** SQL statement to drop "entry" table. */
private static final String SQL_DELETE_ENTRIES =
"DROP TABLE IF EXISTS " + FeedContract.Entry.TABLE_NAME;
public FeedDatabase(Context context) {
super(context, DATABASE_NAME, null, DATABASE_VERSION);
}
@Override
public void onCreate(SQLiteDatabase db) {
db.execSQL(SQL_CREATE_ENTRIES);
}
@Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
// This database is only a cache for online data, so its upgrade policy is
// to simply to discard the data and start over
db.execSQL(SQL_DELETE_ENTRIES);
onCreate(db);
}
}
}