Package com.exonum.binding.core.storage.database

Class TemporaryDb

java.lang.Object

com.exonum.binding.core.proxy.AbstractNativeProxy

com.exonum.binding.core.proxy.AbstractCloseableNativeProxy

com.exonum.binding.core.storage.database.TemporaryDb

All Implemented Interfaces:

CloseableNativeProxy, Database, AutoCloseable

public final class TemporaryDb
extends AbstractCloseableNativeProxy
implements Database

A MerkleDB which stores its data in the temporary directory for testing purposes. It can create both read-only snapshots and read-write forks. The changes made to database forks can be applied to the database state.

The corresponding database is deleted when TemporaryDb is closed.

See Also:

NodeFake

Field Summary

Fields inherited from class com.exonum.binding.core.proxy.AbstractNativeProxy

nativeHandle

Method Summary

Modifier and Type	Method	Description
Fork	createFork(Cleaner cleaner)	Creates a new database fork.
Snapshot	createSnapshot(Cleaner cleaner)	Creates a new snapshot of the database state.
protected void	disposeInternal()	Releases any resources owned by this proxy (e.g., the corresponding native object).
void	merge(Fork fork)	Applies the changes from the given fork to the database state.
static TemporaryDb	newInstance()	Creates a new empty TemporaryDb.

Methods inherited from class com.exonum.binding.core.proxy.AbstractCloseableNativeProxy

close, getNativeHandle

Methods inherited from class com.exonum.binding.core.proxy.AbstractNativeProxy

isValidHandle

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Methods inherited from interface com.exonum.binding.core.proxy.CloseableNativeProxy

close

Method Detail

newInstance

public static TemporaryDb newInstance()

Creates a new empty TemporaryDb.

createSnapshot

public Snapshot createSnapshot(Cleaner cleaner)

Description copied from interface: Database

Creates a new snapshot of the database state.

Specified by:

createSnapshot in interface Database

Parameters:

cleaner - a cleaner to register the snapshot

Returns:

a new snapshot of the database state

createFork

public Fork createFork(Cleaner cleaner)

Description copied from interface: Database

Creates a new database fork.

A fork allows to perform a transaction: a number of independent writes to a database, which then may be atomically applied to the database.

Specified by:

createFork in interface Database

Parameters:

cleaner - a cleaner to register the fork

Returns:

a new database fork

merge

public void merge(Fork fork)

Applies the changes from the given fork to the database state. TemporaryDb can only merge forks that it created itself.

Once this method completes, any indexes created with the fork and the fork itself are closed and cannot be used anymore. Any subsequent operations on these objects will result in IllegalStateException.

Parameters:

fork - a fork to get changes from

Throws:

RuntimeException - if the fork cannot be applied to the database state. The provided fork will be closed

disposeInternal

protected void disposeInternal()

Description copied from class: AbstractCloseableNativeProxy

Releases any resources owned by this proxy (e.g., the corresponding native object).

This method is only called once from AbstractCloseableNativeProxy.close() for a valid proxy and shall not be called directly.

Specified by:

disposeInternal in class AbstractCloseableNativeProxy