Versions Compared

Key

  • This line was added.
  • This line was removed.
  • Formatting was changed.

...

  

LuceneQueryFactory

Code Block
 /**
   * Set page size for a query result. The default page size is 0 which means no pagination.
   * If specified negative value, throw IllegalArgumentException
   * @param pageSize
   * @return itself
   */
  LuceneQueryFactory setPageSize(int pageSize);
  
  /**
   * Set max limit of result for a query
   * If specified limit is less or equal to zero, throw IllegalArgumentException
   * @param limit
   * @return itself
   */
  LuceneQueryFactory setResultLimit(int limit);
  
  /**
   * Set a list of fields for result projection.
   * 
   * @param fieldNames
   * @return itself
   */
  LuceneQueryFactory setProjectionFields(String... fieldNames);
  
  /**
   * Create wrapper object for lucene's QueryParser object using default standard analyzer.
   * The queryString is using lucene QueryParser's syntax. QueryParser is for easy-to-use 
   * with human understandable syntax. 
   *  
   * @param regionName region name
   * @param indexName index name
   * @param queryString query string in lucene QueryParser's syntax
   * @param K the key type in the query results
   * @param V the value type in the query results
   * @return LuceneQuery object
   * @throws ParseException
   */
  public <K, V> LuceneQuery<K, V> create(String indexName, String regionName, String queryString) 
      throws ParseException;
  /**
   * Creates a wrapper object for Lucene's Query object. This {@link LuceneQuery} builder method could be used in
   * advanced cases, such as cases where Lucene's Query object construction needs Lucene's API over query string. The
   * {@link QueryDeserializer} will be used to re-construct the Lucene Query object on remote hosts.
   * 
   * @param indexName index name
   * @param regionName region name
   * @param provider constructs and provides a Lucene Query object
   * @param K the key type in the query results
   * @param V the value type in the query results
   * @return LuceneQuery object
   */
  public <K, V> LuceneQuery<K, V> create(String indexName, String regionName, LuceneQueryProvider provider);

/**
 * The instances of this class will be used for distributing Lucene Query objects and re-constructing the Query object.
 * If necessary the implementation needs to take care of serializing and de-serializing Lucene Query object. Geode
 * respects the DataSerializable contract to provide optimal object serialization. For instance,
 * {@link LuceneQueryProvider}'s toData method will be used to serialize it when it is sent to another member of the
 * distributed system. Implementation of DataSerializable can provide a zero-argument constructor that will be invoked
 * when they are read with DataSerializer.readObject.
 */
public interface LuceneQueryProvider extends Serializable {
  /**
   * @return A Lucene Query object which could be used for executing Lucene Search on indexed data
   * @param The local lucene index the query is being constructed against.
   * @throws QueryException if the provider fails to construct the query object
   */
  public Query getQuery(LuceneIndex index) throws QueryException;
}

LuceneQuery

Code Block
/**
 * Provides wrapper object of Lucene's Query object and execute the search. 
 * <p>Instances of this interface are created using
 * {@link LuceneQueryFactory#create}.
 * 
 */
public interface LuceneQuery {
  /**
   * Execute the search and get results. 
   */
  public LuceneQueryResults<?> search();
  
  /**
   * Get page size setting of current query. 
   */
  public int getPageSize();
  
  /**
   * Get limit size setting of current query. 
   */
  public int getLimit();
  
  /**
   * Get projected fields setting of current query. 
   */
  public String[] getProjectedFieldNames();
}
 

LuceneResultStruct

Code Block
  /**
   * Return the value associated with the given field name
   *
   * @param fieldName the String name of the field
   * @return the value associated with the specified field
   * @throws IllegalArgumentException If this struct does not have a field named fieldName
   */
  public Object getProjectedField(String fieldName);
  
  /**
   * Return key of the entry
   *
   * @return key
   * @throws IllegalArgumentException If this struct does not contain key
   */
  public Object getKey();
  
  /**
   * Return value of the entry
   *
   * @return value the whole domain object
   * @throws IllegalArgumentException If this struct does not contain value
   */
  public Object getValue();
  
  /**
   * Return score of the query 
   *
   * @return score
   * @throws IllegalArgumentException If this struct does not contain score
   */
  public Double getScore();
  
   
  /**
   * Get the values in same order as result types
   * @return the array of values
   */
  public Object[] getResultValues();
}

    Examples

Code Block
// Get LuceneService
LuceneService luceneService = LuceneServiceProvider.get(cache);

// Create Index on fields with default analyzer:
LuceneIndex index = luceneService.createIndex(indexName, regionName, "field1", "field2", "field3");

// create index on fields with specified analyzer:
LuceneIndex index = luceneService.createIndex(indexName, regionName, analyzerPerField);

// Create Query
LuceneQuery query = luceneService.createLuceneQueryFactory().setLimit(200).setPageSize(20)
  .setResultType(SCORE, VALUE, KEY).setFieldProjection("field1", "field2")
  .create(indexName, regionName, querystring, analyzer);

// Search using Query
LuceneQueryResults results = query.search();

List values = results.getNextPage(); // return all results in one page

// Pagination
while (results.hasNextPage())
  List page = results.getNextPage(); // return result page by page

  for (LuceneResultStruct r : page) {
    System.out.prinlntprintln(r.getValue());
  }
}

 

Gfsh API

 

Code Block
// Create Index
gfsh> create lucene index --name=indexName --region=/orders --fields=customer,tags

// Destory Index
gfsh> destroy lucene index --name=indexName --region=/orders

Execute Lucene query
gfsh> lucene query --regionName=/orders -queryStrings="" --limit=100 page-size=10

 

XML Configuration 

 

Code Block
<cache
    xmlns="http://schema.pivotal.io/gemfire/cache"
    xmlns:lucene="http://geode.incubator.apache.org/schema/lucene"
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xsi:schemaLocation="http://schema.pivotal.io/gemfire/cache
        http://schema.pivotal.io/gemfire/cache/cache-9.0.xsd
        http://geode.incubator.apache.org/schema/lucene
        http://geode.incubator.apache.org/schema/lucene/lucene-1.0.xsd"
    version="9.0">

<region name="region">  
 <lucene:index name="luceneIndex">
             <lucene:field name="fieldName" analyzer="KeywordAnalyzer"/> 
 </lucene:index>
</region>

 

REST API

TBD - But using solr to provide a REST API might make a lot of sense

Spring Data GemFire Support

TBD - But the Searchable annotation described in this blog might be a good place to start.

Implementation Flowchart

 

...