dis/04/src/PersistenceManager.java

64 lines
1.2 KiB
Java

import org.jetbrains.annotations.Contract;
/**
* Persistence manager using the Singleton pattern.
*/
public class PersistenceManager
{
private final static PersistenceManager instance;
static {
try {
instance = new PersistenceManager();
}
catch (Throwable e) {
throw new RuntimeException(e.getMessage());
}
}
/**
* Returns an instance of the persistence manager.
* @return instance
*/
@Contract(pure = true)
public static PersistenceManager getInstance()
{
return instance;
}
/**
* private constructor
*/
private PersistenceManager()
{}
/**
* Begins the transaction and returns the transaction ID.
* @return transaction ID
*/
public int beginTransaction()
{
return 0;
}
/**
* Commits the transaction specified by given ID.
* @param taid transaction ID
*/
public void commit(int taid)
{
}
/**
* Writes given data into given page in given transaction.
* @param taid transaction ID
* @param pageid page ID
* @param data data
*/
public void write(int taid, int pageid, String data)
{
}
}