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A library jar that provides APIs for Applications written for the Google Android Platform.
/*
* Copyright (C) 2016 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 androidx.room;
import android.content.Context;
import androidx.annotation.NonNull;
/**
* Utility class for Room.
*/
@SuppressWarnings("unused")
public class Room {
static final String LOG_TAG = "ROOM";
/**
* The master table where room keeps its metadata information.
*/
public static final String MASTER_TABLE_NAME = RoomMasterTable.TABLE_NAME;
private static final String CURSOR_CONV_SUFFIX = "_CursorConverter";
/**
* Creates a RoomDatabase.Builder for a persistent database. Once a database is built, you
* should keep a reference to it and re-use it.
*
* @param context The context for the database. This is usually the Application context.
* @param klass The abstract class which is annotated with {@link Database} and extends
* {@link RoomDatabase}.
* @param name The name of the database file.
* @param The type of the database class.
* @return A {@code RoomDatabaseBuilder} which you can use to create the database.
*/
@SuppressWarnings("WeakerAccess")
@NonNull
public static RoomDatabase.Builder databaseBuilder(
@NonNull Context context, @NonNull Class klass, @NonNull String name) {
//noinspection ConstantConditions
if (name == null || name.trim().length() == 0) {
throw new IllegalArgumentException("Cannot build a database with null or empty name."
+ " If you are trying to create an in memory database, use Room"
+ ".inMemoryDatabaseBuilder");
}
return new RoomDatabase.Builder<>(context, klass, name);
}
/**
* Creates a RoomDatabase.Builder for an in memory database. Information stored in an in memory
* database disappears when the process is killed.
* Once a database is built, you should keep a reference to it and re-use it.
*
* @param context The context for the database. This is usually the Application context.
* @param klass The abstract class which is annotated with {@link Database} and extends
* {@link RoomDatabase}.
* @param The type of the database class.
* @return A {@code RoomDatabaseBuilder} which you can use to create the database.
*/
@NonNull
public static RoomDatabase.Builder inMemoryDatabaseBuilder(
@NonNull Context context, @NonNull Class klass) {
return new RoomDatabase.Builder<>(context, klass, null);
}
@SuppressWarnings({"TypeParameterUnusedInFormals", "ClassNewInstance"})
@NonNull
static T getGeneratedImplementation(Class klass, String suffix) {
final String fullPackage = klass.getPackage().getName();
String name = klass.getCanonicalName();
final String postPackageName = fullPackage.isEmpty()
? name
: (name.substring(fullPackage.length() + 1));
final String implName = postPackageName.replace('.', '_') + suffix;
//noinspection TryWithIdenticalCatches
try {
@SuppressWarnings("unchecked")
final Class aClass = (Class) Class.forName(
fullPackage.isEmpty() ? implName : fullPackage + "." + implName);
return aClass.newInstance();
} catch (ClassNotFoundException e) {
throw new RuntimeException("cannot find implementation for "
+ klass.getCanonicalName() + ". " + implName + " does not exist");
} catch (IllegalAccessException e) {
throw new RuntimeException("Cannot access the constructor"
+ klass.getCanonicalName());
} catch (InstantiationException e) {
throw new RuntimeException("Failed to create an instance of "
+ klass.getCanonicalName());
}
}
/** @deprecated This type should not be instantiated as it contains only static methods. */
@Deprecated
@SuppressWarnings("PrivateConstructorForUtilityClass")
public Room() {
}
}