org.janusgraph.diskstorage.indexing

Interface IndexProvider

All Superinterfaces:

IndexInformation

public interface IndexProvider
extends IndexInformation

External index for querying. An index can contain an arbitrary number of index stores which are updated and queried separately.

Author:

Matthias Broecheler ([email protected])

Field Summary

Fields

Modifier and Type	Field and Description
static char	REPLACEMENT_CHAR

Method Summary

Modifier and Type	Method and Description
BaseTransactionConfigurable	beginTransaction(BaseTransactionConfig config) Returns a transaction handle for a new index transaction.
static void	checkKeyValidity(String key)
void	clearStorage() Clears the index and removes all entries in all stores.
void	close() Closes the index
boolean	exists() Checks whether the index exists.
void	mutate(Map<String,Map<String,IndexMutation>> mutations, KeyInformation.IndexRetriever information, BaseTransaction tx) Mutates the index (adds and removes fields or entire documents)
Stream<String>	query(IndexQuery query, KeyInformation.IndexRetriever information, BaseTransaction tx) Executes the given query against the index.
Stream<RawQuery.Result<String>>	query(RawQuery query, KeyInformation.IndexRetriever information, BaseTransaction tx) Executes the given raw query against the index
void	register(String store, String key, KeyInformation information, BaseTransaction tx) This method registers a new key for the specified index store with the given data type.
void	restore(Map<String,Map<String,List<IndexEntry>>> documents, KeyInformation.IndexRetriever information, BaseTransaction tx) Restores the index to the state of the primary data store as given in the documents variable.
Long	totals(RawQuery query, KeyInformation.IndexRetriever information, BaseTransaction tx) Executes the given raw query against the index and returns the total hits.

Methods inherited from interface org.janusgraph.diskstorage.indexing.IndexInformation

getFeatures, mapKey2Field, supports, supports

Field Detail

REPLACEMENT_CHAR

static final char REPLACEMENT_CHAR

See Also:

Constant Field Values

Method Detail

checkKeyValidity

static void checkKeyValidity(String key)

register

void register(String store,
              String key,
              KeyInformation information,
              BaseTransaction tx)
       throws BackendException

This method registers a new key for the specified index store with the given data type. This allows the IndexProvider to prepare the index if necessary. It is expected that this method is first called with each new key to inform the index of the expected type before the key is used in any documents.

Parameters:

store - Index store

key - New key to register

information - Information on the key to register

tx - enclosing transaction

Throws:

BackendException

mutate

void mutate(Map<String,Map<String,IndexMutation>> mutations,
            KeyInformation.IndexRetriever information,
            BaseTransaction tx)
     throws BackendException

Mutates the index (adds and removes fields or entire documents)

Parameters:

mutations - Updates to the index. First map contains all the mutations for each store. The inner map contains all changes for each document in an IndexMutation.

information - Information on the keys used in the mutation accessible through KeyInformation.IndexRetriever.

tx - Enclosing transaction

Throws:

BackendException

See Also:

IndexMutation

restore

void restore(Map<String,Map<String,List<IndexEntry>>> documents,
             KeyInformation.IndexRetriever information,
             BaseTransaction tx)
      throws BackendException

Restores the index to the state of the primary data store as given in the documents variable. When this method returns, the index records for the given documents exactly matches the provided data. Unlike mutate(java.util.Map, KeyInformation.IndexRetriever, BaseTransaction) this method does not do a delta-update, but entirely replaces the documents with the provided data or deletes them if the document content is empty.

Parameters:

documents - The outer map maps stores to documents, the inner contains the documents mapping document ids to the document content which is a list of IndexEntry. If that list is empty, that means this document should not exist and ought to be deleted.

information - Information on the keys used in the mutation accessible through KeyInformation.IndexRetriever.

tx - Enclosing transaction

Throws:

BackendException

query

Stream<String> query(IndexQuery query,
                     KeyInformation.IndexRetriever information,
                     BaseTransaction tx)
              throws BackendException

Executes the given query against the index.

Parameters:

query - Query to execute

information - Information on the keys used in the query accessible through KeyInformation.IndexRetriever.

tx - Enclosing transaction

Returns:

The ids of all matching documents

Throws:

BackendException

See Also:

IndexQuery

query

Stream<RawQuery.Result<String>> query(RawQuery query,
                                      KeyInformation.IndexRetriever information,
                                      BaseTransaction tx)
                               throws BackendException

Executes the given raw query against the index

Parameters:

query - Query to execute

information - Information on the keys used in the query accessible through KeyInformation.IndexRetriever.

tx - Enclosing transaction

Returns:

Results objects for all matching documents (i.e. document id and score)

Throws:

BackendException

See Also:

RawQuery

totals

Long totals(RawQuery query,
            KeyInformation.IndexRetriever information,
            BaseTransaction tx)
     throws BackendException

Executes the given raw query against the index and returns the total hits. e.g. limit=0

Parameters:

query - Query to execute

information - Information on the keys used in the query accessible through KeyInformation.IndexRetriever.

tx - Enclosing transaction

Returns:

Long total hits for query

Throws:

BackendException

See Also:

RawQuery

beginTransaction

BaseTransactionConfigurable beginTransaction(BaseTransactionConfig config)
                                      throws BackendException

Returns a transaction handle for a new index transaction.

Returns:

New Transaction Handle

Throws:

BackendException

close

void close()
    throws BackendException

Closes the index

Throws:

BackendException

clearStorage

void clearStorage()
           throws BackendException

Clears the index and removes all entries in all stores.

Throws:

BackendException

exists

boolean exists()
        throws BackendException

Checks whether the index exists.

Returns:

Flag indicating whether index exists

Throws:

BackendException