Package org.somda.sdc.biceps.common.access

Class ReadTransactionImpl

java.lang.Object

org.somda.sdc.biceps.common.access.ReadTransactionImpl

All Implemented Interfaces:

AutoCloseable, MdibAccess, ReadTransaction

public class ReadTransactionImpl
extends Object
implements ReadTransaction

Default implementation of ReadTransaction.

Constructor Summary

Constructors

Constructor	Description
ReadTransactionImpl(MdibStorage mdibStorage, Lock lock)

Method Summary

Modifier and Type	Method	Description
void	close()	Creates an empty default to override AutoCloseable.close().
<T extends AbstractContextState> List<T>	findContextStatesByType(Class<T> stateClass)	Gets all context states of a specific type.
<T extends AbstractDescriptor> Collection<MdibEntity>	findEntitiesByType(Class<T> type)	Searches all entities that match a specific type.
<T extends AbstractDescriptor> List<MdibEntity>	getChildrenByType(String handle, Class<T> type)	Resolves the children of a specific type given a parent handle.
List<AbstractContextState>	getContextStates()	Gets all context states.
List<AbstractContextState>	getContextStates(String descriptorHandle)	Finds all context states of a certain descriptor.
<T extends AbstractContextState> List<T>	getContextStates(String descriptorHandle, Class<T> stateClass)	Finds all context states of a certain descriptor given a state class.
Optional<AbstractDescriptor>	getDescriptor(String handle)	Retrieves a specific abstract descriptor of the hosted Mdib.
<T extends AbstractDescriptor> Optional<T>	getDescriptor(String handle, Class<T> descrClass)	Retrieves a specific descriptor of the hosted Mdib.
Optional<MdibEntity>	getEntity(String handle)	Gets an MdibEntity object with a specific handle.
BigInteger	getMdDescriptionVersion()	The latest known MD description version.
MdibVersion	getMdibVersion()	The latest known MDIB version.
BigInteger	getMdStateVersion()	The latest known MD description version.
List<MdibEntity>	getRootEntities()	Gets all MdibEntity objects that are root elements.
Optional<AbstractState>	getState(String handle)	Retrieves a specific abstract state of the hosted Mdib.
<T extends AbstractState> Optional<T>	getState(String handle, Class<T> stateClass)	Retrieves a specific state of the hosted Mdib.

Methods inherited from class java.lang.Object

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

Constructor Detail

ReadTransactionImpl

public ReadTransactionImpl(MdibStorage mdibStorage,
                           Lock lock)

Method Detail

close

public void close()

Description copied from interface: ReadTransaction

Creates an empty default to override AutoCloseable.close().

AutoCloseable.close() throws an exception whereas ReadTransaction is supposed to be no-throw. In order to avoid a boiler plate catch branch that is never visited when using try(...) with ReadTransaction, this function overrides the AutoCloseable.close() function without throwing a checked exception.

Specified by:

close in interface AutoCloseable

Specified by:

close in interface ReadTransaction

See Also:

AutoCloseable.close()

getMdibVersion

public MdibVersion getMdibVersion()

Description copied from interface: MdibAccess

The latest known MDIB version.

This object returns the last known MDIB version which in case of remote access may not necessarily reflect the MDIB version of the whole MDIB. For local access the MDIB version reflects the latest state.

Specified by:

getMdibVersion in interface MdibAccess

Returns:

the latest known MDIB version.

getMdDescriptionVersion

public BigInteger getMdDescriptionVersion()

Description copied from interface: MdibAccess

The latest known MD description version.

This object returns the last known MDIB version which in case of remote access may be outdated. For local access the MD description version reflects the latest state.

Specified by:

getMdDescriptionVersion in interface MdibAccess

Returns:

the latest known MD description version.

getMdStateVersion

public BigInteger getMdStateVersion()

Description copied from interface: MdibAccess

The latest known MD description version.

This object returns the last known MDIB version which in case of remote access may be outdated. For local access the MD description version reflects the latest state.

Specified by:

getMdStateVersion in interface MdibAccess

Returns:

The latest known MD state version.

getDescriptor

public <T extends AbstractDescriptor> Optional<T> getDescriptor(String handle,
                                                                Class<T> descrClass)

Description copied from interface: MdibAccess

Retrieves a specific descriptor of the hosted Mdib.

Specified by:

getDescriptor in interface MdibAccess

Type Parameters:

T - any descriptor type.

Parameters:

handle - Handle name of the descriptor.

descrClass - Class to cast to. If cast fails, Optional.empty() will be returned.

Returns:

Optional of the requested descriptor or Optional.empty() if not found or something went wrong.

getDescriptor

public Optional<AbstractDescriptor> getDescriptor(String handle)

Description copied from interface: MdibAccess

Retrieves a specific abstract descriptor of the hosted Mdib.

Specified by:

getDescriptor in interface MdibAccess

Parameters:

handle - Handle name of the descriptor.

Returns:

Optional of the requested descriptor or Optional.empty() if not found or something went wrong.

getEntity

public Optional<MdibEntity> getEntity(String handle)

Description copied from interface: MdibAccess

Gets an MdibEntity object with a specific handle.

Specified by:

getEntity in interface MdibAccess

Parameters:

handle - the handle to seek.

Returns:

the entity of Optional.empty() if not found.

getRootEntities

public List<MdibEntity> getRootEntities()

Description copied from interface: MdibAccess

Gets all MdibEntity objects that are root elements.

Specified by:

getRootEntities in interface MdibAccess

Returns:

the root elements, i.e., entities whose descriptors are of type MdsDescriptor.

getState

public Optional<AbstractState> getState(String handle)

Description copied from interface: MdibAccess

Retrieves a specific abstract state of the hosted Mdib.

Specified by:

getState in interface MdibAccess

Parameters:

handle - the state or descriptor handle of the state to request (descriptor handle is used in case of single states).

Returns:

Optional of the requested state or Optional.empty() if not found or something went wrong.

getState

public <T extends AbstractState> Optional<T> getState(String handle,
                                                      Class<T> stateClass)

Description copied from interface: MdibAccess

Retrieves a specific state of the hosted Mdib.

Specified by:

getState in interface MdibAccess

Type Parameters:

T - any state type.

Parameters:

handle - the state or descriptor handle of the state to request (descriptor handle is used in case of single states).

stateClass - the class to cast to. If cast fails, Optional.empty() will be returned.

Returns:

Optional of the requested state or Optional.empty() if not found or something went wrong.

getContextStates

public <T extends AbstractContextState> List<T> getContextStates(String descriptorHandle,
                                                                 Class<T> stateClass)

Description copied from interface: MdibAccess

Finds all context states of a certain descriptor given a state class.

Attention: collections may be created on function call, hence be careful with performance issues.

Specified by:

getContextStates in interface MdibAccess

Type Parameters:

T - any context state type.

Parameters:

descriptorHandle - the descriptor handle to seek.

stateClass - the class to filter for.

Returns:

a list of the context states of descriptorHandle.

getContextStates

public List<AbstractContextState> getContextStates(String descriptorHandle)

Description copied from interface: MdibAccess

Finds all context states of a certain descriptor.

Attention: collections may be created on function call, hence be careful with performance issues.

Specified by:

getContextStates in interface MdibAccess

Parameters:

descriptorHandle - the descriptor handle to seek.

Returns:

a list of the context states of descriptorHandle.

getContextStates

public List<AbstractContextState> getContextStates()

Description copied from interface: MdibAccess

Gets all context states.

Attention: collections may be created on function call, hence be careful with performance issues.

Specified by:

getContextStates in interface MdibAccess

Returns:

a list of all context states.

findContextStatesByType

public <T extends AbstractContextState> List<T> findContextStatesByType(Class<T> stateClass)

Description copied from interface: MdibAccess

Gets all context states of a specific type.

Attention: collections may be created on function call, hence be careful with performance issues.

Specified by:

findContextStatesByType in interface MdibAccess

Type Parameters:

T - the type to filter for.

Parameters:

stateClass - the class information to filter for.

Returns:

a list of all context states of the specific type.

findEntitiesByType

public <T extends AbstractDescriptor> Collection<MdibEntity> findEntitiesByType(Class<T> type)

Description copied from interface: MdibAccess

Searches all entities that match a specific type.

Specified by:

findEntitiesByType in interface MdibAccess

Type Parameters:

T - the descriptor type defined by the class.

Parameters:

type - the class to filter for.

Returns:

a collection of entities where type matches.

getChildrenByType

public <T extends AbstractDescriptor> List<MdibEntity> getChildrenByType(String handle,
                                                                         Class<T> type)

Description copied from interface: MdibAccess

Resolves the children of a specific type given a parent handle.

Specified by:

getChildrenByType in interface MdibAccess

Type Parameters:

T - the descriptor type defined by the class.

Parameters:

handle - the parent handle of the entity.

type - The class to filter for.

Returns:

a list of children that matches type (while preserving ordering).