package de.swm.gwt.storage;
import com.google.code.gwt.database.client.GenericRow;
import com.google.code.gwt.database.client.service.*;
/**
* SQL storage wrapper for {@see BigLocalStoage}.
* @author Daniel Wiese
*/
@Connection(name = "SWMLocalStorage", version = "1.0",
description = "LocalStroge for big Data", maxsize = SQLStorageLayer.SIZE_IN_MB * 1024 * 1024)
public interface SQLStorageLayer extends DataService {
/**
* Defines the size of current local storage (Database size)
*/
int SIZE_IN_MB = 25;
/**
* Makes sure that the 'swmstorage' table exists in the Database.
*/
@Update("CREATE TABLE IF NOT EXISTS swmstorage ("
+ "id STRING NOT NULL PRIMARY KEY, "
+ "value STRING)")
void initTable(VoidCallback callback);
/**
* Inserts a value or uptates the value.
*/
@Update("INSERT INTO swmstorage (id, value) VALUES ({key}, {value})")
void insertValue(String key, String value, VoidCallback callback);
/**
* Updates a value.
*/
@Update("UPDATE swmstorage SET value = {value} WHERE id = {key}")
void updateValue(String key, String value, VoidCallback callback);
/**
* Delete a Value.
*/
@Update("DELETE FROM swmstorage WHERE id = {key}")
void deleteKeyAndValue(String key, VoidCallback callback);
/**
* Delete a Value.
*/
@Update("DELETE FROM swmstorage")
void deleteAll(VoidCallback callback);
/**
* Returns a value.
*/
@Select("SELECT * FROM swmstorage")
void getAllValues(ListCallback<GenericRow> callback);
/**
* Obtains the number elements in the database.
*/
@Select("SELECT count(*) FROM swmstorage")
void getCount(ScalarCallback<Integer> callback);
/**
* Obtains the version number of the SQLite database.
*/
@Select("SELECT sqlite_version()")
void getSqliteVersion(ScalarCallback<String> callback);
}