org.apache.xindice.core.indexer
Interface Indexer

All Superinterfaces:

Configurable, DBObject, Named

All Known Implementing Classes:

NameIndexer, ValueIndexer

public interface Indexer

extends Named, DBObject, Configurable

Indexer is the abstract indexing interface for Xindice. An Indexer object is implemented in order to retrieve and manage indexes.

Any number of Indexer instances may be associated with a single Collection. The type of Indexer utilized by a query depends on the 'Style' of Indexer and the type of QueryResolver that is being used to performt he query. Currently, Xindice only internally supports one kind of Indexer: 'XPath'.

Field Summary

static java.lang.String	STYLE_FULLTEXT
static java.lang.String	STYLE_NODENAME
static java.lang.String	STYLE_NODEVALUE

Method Summary

void	add(java.lang.String value, Key key, int pos, int len, short elemID, short attrID) add adds a Document to the Indexer.
void	flush() flush forcefully flushes any unwritten buffers to disk.
java.lang.String	getIndexStyle() getIndexStyle returns the Index style.
java.lang.String	getPattern() getPattern returns the pattern recognized by this Indexer.
IndexMatch[]	queryMatches(IndexQuery query) queryMatches retrieves a set of MatchEntry instances that match the supplied query.
void	remove(java.lang.String value, Key key, int pos, int len, short elemID, short attrID) remove removes all references to the specified Key from the Indexer.
void	setCollection(Collection collection) setCollection tells the Indexer who its parent is.

Methods inherited from interface org.apache.xindice.util.Named

getName

Methods inherited from interface org.apache.xindice.core.DBObject

close, create, drop, exists, isOpened, open

Methods inherited from interface org.apache.xindice.util.Configurable

getConfig, setConfig

Field Detail

STYLE_NODENAME

public static final java.lang.String STYLE_NODENAME

STYLE_NODEVALUE

public static final java.lang.String STYLE_NODEVALUE

STYLE_FULLTEXT

public static final java.lang.String STYLE_FULLTEXT

Method Detail

setCollection

public void setCollection(Collection collection)

setCollection tells the Indexer who its parent is.

Parameters:

collection - The owner Collection

getIndexStyle

public java.lang.String getIndexStyle()

getIndexStyle returns the Index style. Different query languages will need to draw from different indexing styles. For example, A query that is written in quilt will require XPath indexing.

Returns:

The index style

getPattern

public java.lang.String getPattern()

getPattern returns the pattern recognized by this Indexer. Patterns must be in the form of (elem|*)[@(attr|*)] to tell the IndexManager which element types to send to it, so for example:

    contact@name  Indexes all contacts by name attribute
    memo          Indexes the text of all memo elements
    contact@*     Indexes all contact attributes
    *@name        Indexes the name attribute for all elements
    *             Indexes the text of all elements
    *@*           Indexes all attributes of all elements
 

These patterns are used by the IndexManager when handling SAX events. All events that match the specified pattern will result in an add or remove call to the Indexer.

Returns:

The Pattern used

remove

public void remove(java.lang.String value,
                   Key key,
                   int pos,
                   int len,
                   short elemID,
                   short attrID)
            throws DBException

remove removes all references to the specified Key from the Indexer.

Parameters:

value - The value to remove

key - The Object ID

pos - The offset into the stream the Element occurs at

len - The length of the substream for the Element

elemID - The Element ID of the value

attrID - The Attribute ID of the value (if any, else -1)

add

public void add(java.lang.String value,
                Key key,
                int pos,
                int len,
                short elemID,
                short attrID)
         throws DBException

add adds a Document to the Indexer.

Parameters:

value - The value to remove

key - The Object ID

pos - The offset into the stream the Element occurs at

len - The length of the substream for the Element

elemID - The Element ID of the value

attrID - The Attribute ID of the value (if any, else -1)

queryMatches

public IndexMatch[] queryMatches(IndexQuery query)
                          throws DBException

queryMatches retrieves a set of MatchEntry instances that match the supplied query. The matches are then used by the QueryEngine in co-sequential processing. If this indexer doesn't support the passed value, it should return 'null'. If no matches are found, it should return an empty set. queryMatches will typically be used in XPath processing.

Parameters:

query - The IndexQuery to use

Returns:

The resulting matches

flush

public void flush()
           throws DBException

flush forcefully flushes any unwritten buffers to disk.