Interface for custom field types
The CustomFieldType interface marks Solr custom field types and provides their actual stored field type.
DataStax Enterprise implements a CustomFieldType interface that marks Solr custom field types and provides their actual stored field type. The custom field type stores an integer trie field as a string representing a comma separated list of integer values: when indexed, the string is split into its integer values, each one indexed as a trie integer field. This class effectively implements a multi-valued field based on its string representation.
A CustomFieldType can override this method to provide the FieldType for the binary response writer to look at when it determines whether to call the field's toObject(). This allows the binary response writer, for instance, to return java.util.Date in place of text for a CustomFieldType that extends TrieDateField.
public Class<? extends FieldType> getKnownType()
{
return getClass();
}
See
the example reference implementation. Procedure
To use the CustomFieldType interface:
Example
Reference implementation
Here is an example of a custom field type class:
package com.datastax.bdp.search.solr.functional;
import com.datastax.bdp.search.solr.CustomFieldType;
import java.util.ArrayList;
import java.util.List;
import org.apache.lucene.index.IndexableField;
import org.apache.solr.schema.FieldType;
import org.apache.solr.schema.SchemaField;
import org.apache.solr.schema.StrField;
import org.apache.solr.schema.TrieField;
public class CustomTestField extends TrieField implements CustomFieldType
{
public CustomTestField()
{
this.type = TrieField.TrieTypes.INTEGER;
}
@Override
public FieldType getStoredFieldType()
{
return new StrField();
}
@Override
public boolean multiValuedFieldCache()
{
return true;
}
@Override
public ListIndexableField createFields(SchemaField sf, Object value)
{
String[] values = ((String) value).split(" ");
ListIndexableField fields = new ArrayListIndexableField();
for (String v : values)
{
fields.add(createField(sf, v));
}
return fields;
}
@Override
public String toInternal(String value)
{
return value;
}
@Override
public String toExternal(IndexableField f)
{
return f.stringValue();
}
public Class<? extends FieldType> getKnownType()
{
return TrieField.class;
}
}