com.bigdata.bop

Class NamedSolutionSetRefUtility

java.lang.Object

com.bigdata.bop.NamedSolutionSetRefUtility

public class NamedSolutionSetRefUtility
extends Object

Utility class for INamedSolutionSetRefs.

Author:

Bryan Thompson

Constructor Summary

Constructors

Constructor and Description
NamedSolutionSetRefUtility()

Method Summary

Methods

Modifier and Type	Method and Description
static String	getFQN(String namespace, String localName, IVariable[] joinVars) Return the fully qualified name for a named solution set NOT attached to a query.
static StringBuilder	getPrefix(String namespace) The prefix that may be used to identify all named solution sets belonging to the specified KB namespace.
static StringBuilder	getPrefix(String namespace, String localName) The prefix that may be used to identify all named solution sets belonging to the specified KB namespace and having the specified localName.
static ICloseableIterator<IBindingSet[]>	getSolutionSet(ISolutionSetManager sparqlCache, IBTreeManager localIndexManager, String namespace, long timestamp, String localName, IVariable[] joinVars, int chunkCapacity) Resolve the pre-existing named solution set returning an iterator that will visit the solutions (access path scan).
static ISolutionSetStats	getSolutionSetStats(ISolutionSetManager sparqlCache, IBTreeManager localIndexManager, String namespace, long timestamp, String localName, IVariable[] joinVars) Resolve the pre-existing named solution set returning its ISolutionSetStats.
static INamedSolutionSetRef	newInstance(String namespace, long timestamp, String localName, IVariable[] joinVars) Factory for INamedSolutionSetRefs that will be resolved against a KB view identified by a namespace and timestamp.
static INamedSolutionSetRef	newInstance(UUID queryId, String namedSet, IVariable[] joinVars) Factory for INamedSolutionSetRefs that will be resolved against the IRunningQuery identified by the specified queryId.
static INamedSolutionSetRef	valueOf(String s) Parses the INamedSolutionSetRef.toString() representation, returning an instance of that interface.

Methods inherited from class java.lang.Object

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

Constructor Detail

NamedSolutionSetRefUtility

public NamedSolutionSetRefUtility()

Method Detail

newInstance

public static INamedSolutionSetRef newInstance(UUID queryId,
                               String namedSet,
                               IVariable[] joinVars)

Factory for INamedSolutionSetRefs that will be resolved against the IRunningQuery identified by the specified queryId.

Parameters:

queryId - The UUID of the IRunningQuery where you need to look to find the data (optional). When null, you must look at the current query. When non-null you must look at the specified query. See BLZG-1493.

namedSet - The application level name for the named solution set (required).

joinVars - The join variables (required, but may be an empty array).

See Also:

NPE in nested star property paths

newInstance

public static INamedSolutionSetRef newInstance(String namespace,
                               long timestamp,
                               String localName,
                               IVariable[] joinVars)

Factory for INamedSolutionSetRefs that will be resolved against a KB view identified by a namespace and timestamp.

Parameters:

namespace - The bigdata namespace of the AbstractTripleStore where you need to look to find the data (required).

timestamp - The timestamp of the view.

localName - The application level name for the named solution set (required).

joinVars - The join variables (required, but may be an empty array).

valueOf

public static INamedSolutionSetRef valueOf(String s)

Parses the INamedSolutionSetRef.toString() representation, returning an instance of that interface.

See Also:

NamedSolutionSetRef.toString()

getFQN

public static String getFQN(String namespace,
            String localName,
            IVariable[] joinVars)

Return the fully qualified name for a named solution set NOT attached to a query.

Note: this includes the namespace (to keep the named solution sets distinct for different KB instances) and the ordered list of key components (so we can identify different index orders for the same solution set).

Note: This does not allow duplicate indices of different types (BTree versus HTree) for the same key orders as their FQNs would collide.

Note: All index orders for the same "namedSet" will share a common prefix.

Note: All named solution set for the same KB will share a common prefix, and that prefix will be distinct from any other index.

Parameters:

namespace - The KB namespace.

localName - The local (aka application) name for the named solution set.

joinVars - The ordered set of key components (differentiates among different indices for the same named solution set).

Returns:

The fully qualified name.

getPrefix

public static StringBuilder getPrefix(String namespace)

The prefix that may be used to identify all named solution sets belonging to the specified KB namespace.

Parameters:

namespace - The KB namespace.

Returns:

The prefix shared by all solution sets for that KB namespace.

getPrefix

public static StringBuilder getPrefix(String namespace,
                      String localName)

The prefix that may be used to identify all named solution sets belonging to the specified KB namespace and having the specified localName. This may be used to find the different indices over the same named solution set when there is more than one index order for that named solution set.

Parameters:

namespace - The KB namespace.

localName - The application name for the named solution set.

Returns:

The prefix shared by all solution sets for that KB namespace and localName.

getSolutionSetStats

public static ISolutionSetStats getSolutionSetStats(ISolutionSetManager sparqlCache,
                                    IBTreeManager localIndexManager,
                                    String namespace,
                                    long timestamp,
                                    String localName,
                                    IVariable[] joinVars)

Resolve the pre-existing named solution set returning its ISolutionSetStats.

Parameters:

sparqlCache -

localIndexManager -

namespace -

timestamp -

localName -

joinVars -

Returns:

The ISolutionSetStats

Throws:

RuntimeException - if the named solution set can not be found. FIXME Drop joinVars here and just do a Name2Addr scan on the value returned by getPrefix(String, String) to see if we can locate an index (regardless of the join variables). It does not matter *which* index we find, as long as it is the same data.

getSolutionSet

public static ICloseableIterator<IBindingSet[]> getSolutionSet(ISolutionSetManager sparqlCache,
                                               IBTreeManager localIndexManager,
                                               String namespace,
                                               long timestamp,
                                               String localName,
                                               IVariable[] joinVars,
                                               int chunkCapacity)

Resolve the pre-existing named solution set returning an iterator that will visit the solutions (access path scan).

This method MUST NOT be used if the named solution set is hung off of an IRunningQuery. In that case, you need to resolve the IRunningQuery using INamedSolutionSetRef.getQueryId() and then resolve the solution set on the IQueryAttributes associated with that IRunningQuery.

Returns:

An iterator that will visit the solutions in the named solution set.

Throws:

RuntimeException - if the named solution set can not be found. FIXME Drop joinVars here and just do a Name2Addr scan on the value returned by getPrefix(String, String) to see if we can locate an index (regardless of the join variables). It does not matter *which* index we find, as long as it is the same data. TODO Provide federation-wide access to a durable named index? The concept would need to be developed further. Would this be a local index exposed to other nodes in the federation? A hash partitioned index? An remote view of a global IIndex?