Package org.h2.fulltext

Class FullTextLucene

java.lang.Object

org.h2.fulltext.FullText

org.h2.fulltext.FullTextLucene

public class FullTextLucene
extends FullText

This class implements the full text search based on Apache Lucene. Most methods can be called using SQL statements as well.

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static class	FullTextLucene.FullTextTrigger	Trigger updates the index when a inserting, updating, or deleting a row.
private static class	FullTextLucene.IndexAccess	A wrapper for the Lucene writer and searcher.

Field Summary

Fields

Modifier and Type	Field	Description
private static java.lang.String	IN_MEMORY_PREFIX	The prefix for a in-memory path.
private static java.util.HashMap<java.lang.String,FullTextLucene.IndexAccess>	INDEX_ACCESS
private static java.lang.String	LUCENE_FIELD_COLUMN_PREFIX
private static java.lang.String	LUCENE_FIELD_DATA
private static java.lang.String	LUCENE_FIELD_MODIFIED
private static java.lang.String	LUCENE_FIELD_QUERY
private static java.lang.String	SCHEMA
protected static boolean	STORE_DOCUMENT_TEXT_IN_INDEX	Whether the text content should be stored in the Lucene index.
private static java.lang.String	TRIGGER_PREFIX

Constructor Summary

Constructors

Constructor	Description
FullTextLucene()

Method Summary

Modifier and Type	Method	Description
protected static java.sql.SQLException	convertException(java.lang.Exception e)	Convert an exception to a fulltext exception.
static void	createIndex(java.sql.Connection conn, java.lang.String schema, java.lang.String table, java.lang.String columnList)	Create a new full text index for a table and column list.
private static void	createOrDropTrigger(java.sql.Connection conn, java.lang.String schema, java.lang.String table, boolean create)
private static void	createTrigger(java.sql.Connection conn, java.lang.String schema, java.lang.String table)	Create the trigger.
static void	dropAll(java.sql.Connection conn)	Drops all full text indexes from the database.
static void	dropIndex(java.sql.Connection conn, java.lang.String schema, java.lang.String table)	Drop an existing full text index for a table.
protected static FullTextLucene.IndexAccess	getIndexAccess(java.sql.Connection conn)	Get the index writer/searcher wrapper for the given connection.
protected static java.lang.String	getIndexPath(java.sql.Connection conn)	Get the path of the Lucene index for this database.
private static void	indexExistingRows(java.sql.Connection conn, java.lang.String schema, java.lang.String table)	Add the existing data to the index.
static void	init(java.sql.Connection conn)	Initializes full text search functionality for this database.
static void	reindex(java.sql.Connection conn)	Re-creates the full text index for this database.
protected static void	removeIndexAccess(java.lang.String indexPath)	Close the index writer and searcher and remove them from the index access set.
private static void	removeIndexFiles(java.sql.Connection conn)
static java.sql.ResultSet	search(java.sql.Connection conn, java.lang.String text, int limit, int offset)	Searches from the full text index for this database.
protected static java.sql.ResultSet	search(java.sql.Connection conn, java.lang.String text, int limit, int offset, boolean data)	Do the search.
static java.sql.ResultSet	searchData(java.sql.Connection conn, java.lang.String text, int limit, int offset)	Searches from the full text index for this database.

Methods inherited from class org.h2.fulltext.FullText

addWords, addWords, asString, closeAll, createResultSet, hasChanged, parseKey, quoteSQL, removeAllTriggers, setColumns, setIgnoreList, setWhitespaceChars, throwException

Methods inherited from class java.lang.Object

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

Field Detail

STORE_DOCUMENT_TEXT_IN_INDEX

protected static final boolean STORE_DOCUMENT_TEXT_IN_INDEX

Whether the text content should be stored in the Lucene index.

INDEX_ACCESS

private static final java.util.HashMap<java.lang.String,FullTextLucene.IndexAccess> INDEX_ACCESS

TRIGGER_PREFIX

private static final java.lang.String TRIGGER_PREFIX

See Also:

Constant Field Values

SCHEMA

private static final java.lang.String SCHEMA

See Also:

Constant Field Values

LUCENE_FIELD_DATA

private static final java.lang.String LUCENE_FIELD_DATA

See Also:

Constant Field Values

LUCENE_FIELD_QUERY

private static final java.lang.String LUCENE_FIELD_QUERY

See Also:

Constant Field Values

LUCENE_FIELD_MODIFIED

private static final java.lang.String LUCENE_FIELD_MODIFIED

See Also:

Constant Field Values

LUCENE_FIELD_COLUMN_PREFIX

private static final java.lang.String LUCENE_FIELD_COLUMN_PREFIX

See Also:

Constant Field Values

IN_MEMORY_PREFIX

private static final java.lang.String IN_MEMORY_PREFIX

The prefix for a in-memory path. This prefix is only used internally within this class and not related to the database URL.

See Also:

Constant Field Values

Constructor Detail

FullTextLucene

public FullTextLucene()

Method Detail

init

public static void init(java.sql.Connection conn)
                 throws java.sql.SQLException

Initializes full text search functionality for this database. This adds the following Java functions to the database:

• FTL_CREATE_INDEX(schemaNameString, tableNameString, columnListString)
• FTL_SEARCH(queryString, limitInt, offsetInt): result set
• FTL_REINDEX()
• FTL_DROP_ALL()

It also adds a schema FTL to the database where bookkeeping information is stored. This function may be called from a Java application, or by using the SQL statements:

 CREATE ALIAS IF NOT EXISTS FTL_INIT FOR
      "org.h2.fulltext.FullTextLucene.init";
 CALL FTL_INIT();
 

Parameters:

conn - the connection

Throws:

java.sql.SQLException - on failure

createIndex

public static void createIndex(java.sql.Connection conn,
                               java.lang.String schema,
                               java.lang.String table,
                               java.lang.String columnList)
                        throws java.sql.SQLException

Create a new full text index for a table and column list. Each table may only have one index at any time.

Parameters:

conn - the connection

schema - the schema name of the table (case sensitive)

table - the table name (case sensitive)

columnList - the column list (null for all columns)

Throws:

java.sql.SQLException - on failure

dropIndex

public static void dropIndex(java.sql.Connection conn,
                             java.lang.String schema,
                             java.lang.String table)
                      throws java.sql.SQLException

Drop an existing full text index for a table. This method returns silently if no index for this table exists.

Parameters:

conn - the connection

schema - the schema name of the table (case sensitive)

table - the table name (case sensitive)

Throws:

java.sql.SQLException - on failure

reindex

public static void reindex(java.sql.Connection conn)
                    throws java.sql.SQLException

Re-creates the full text index for this database. Calling this method is usually not needed, as the index is kept up-to-date automatically.

Parameters:

conn - the connection

Throws:

java.sql.SQLException - on failure

dropAll

public static void dropAll(java.sql.Connection conn)
                    throws java.sql.SQLException

Drops all full text indexes from the database.

Parameters:

conn - the connection

Throws:

java.sql.SQLException - on failure

search

public static java.sql.ResultSet search(java.sql.Connection conn,
                                        java.lang.String text,
                                        int limit,
                                        int offset)
                                 throws java.sql.SQLException

Searches from the full text index for this database. The returned result set has the following column:

• QUERY (varchar): the query to use to get the data. The query does not include 'SELECT * FROM '. Example: PUBLIC.TEST WHERE ID = 1
• SCORE (float) the relevance score as returned by Lucene.

Parameters:

conn - the connection

text - the search query

limit - the maximum number of rows or 0 for no limit

offset - the offset or 0 for no offset

Returns:

the result set

Throws:

java.sql.SQLException - on failure

searchData

public static java.sql.ResultSet searchData(java.sql.Connection conn,
                                            java.lang.String text,
                                            int limit,
                                            int offset)
                                     throws java.sql.SQLException

Searches from the full text index for this database. The result contains the primary key data as an array. The returned result set has the following columns:

• SCHEMA (varchar): the schema name. Example: PUBLIC
• TABLE (varchar): the table name. Example: TEST
• COLUMNS (array of varchar): comma separated list of quoted column names. The column names are quoted if necessary. Example: (ID)
• KEYS (array of values): comma separated list of values. Example: (1)
• SCORE (float) the relevance score as returned by Lucene.

Parameters:

conn - the connection

text - the search query

limit - the maximum number of rows or 0 for no limit

offset - the offset or 0 for no offset

Returns:

the result set

Throws:

java.sql.SQLException - on failure

convertException

protected static java.sql.SQLException convertException(java.lang.Exception e)

Convert an exception to a fulltext exception.

Parameters:

e - the original exception

Returns:

the converted SQL exception

createTrigger

private static void createTrigger(java.sql.Connection conn,
                                  java.lang.String schema,
                                  java.lang.String table)
                           throws java.sql.SQLException

Create the trigger.

Parameters:

conn - the database connection

schema - the schema name

table - the table name

Throws:

java.sql.SQLException - on failure

createOrDropTrigger

private static void createOrDropTrigger(java.sql.Connection conn,
                                        java.lang.String schema,
                                        java.lang.String table,
                                        boolean create)
                                 throws java.sql.SQLException

Throws:

java.sql.SQLException

getIndexAccess

protected static FullTextLucene.IndexAccess getIndexAccess(java.sql.Connection conn)
                                                    throws java.sql.SQLException

Get the index writer/searcher wrapper for the given connection.

Parameters:

conn - the connection

Returns:

the index access wrapper

Throws:

java.sql.SQLException - on failure

getIndexPath

protected static java.lang.String getIndexPath(java.sql.Connection conn)
                                        throws java.sql.SQLException

Get the path of the Lucene index for this database.

Parameters:

conn - the database connection

Returns:

the path

Throws:

java.sql.SQLException - on failure

indexExistingRows

private static void indexExistingRows(java.sql.Connection conn,
                                      java.lang.String schema,
                                      java.lang.String table)
                               throws java.sql.SQLException

Add the existing data to the index.

Parameters:

conn - the database connection

schema - the schema name

table - the table name

Throws:

java.sql.SQLException - on failure

removeIndexFiles

private static void removeIndexFiles(java.sql.Connection conn)
                              throws java.sql.SQLException

Throws:

java.sql.SQLException

removeIndexAccess

protected static void removeIndexAccess(java.lang.String indexPath)
                                 throws java.sql.SQLException

Close the index writer and searcher and remove them from the index access set.

Parameters:

indexPath - the index path

Throws:

java.sql.SQLException - on failure

search

protected static java.sql.ResultSet search(java.sql.Connection conn,
                                           java.lang.String text,
                                           int limit,
                                           int offset,
                                           boolean data)
                                    throws java.sql.SQLException

Do the search.

Parameters:

conn - the database connection

text - the query

limit - the limit

offset - the offset

data - whether the raw data should be returned

Returns:

the result set

Throws:

java.sql.SQLException - on failure