Literal Contains Implementation Details
Works the same as contains but uses the literal property value enabling searches on special characters.
Algorithm:
The Literal Contains search has the following characteristics:
- This search is case in-sensitive.
- It searches on the literal property.
- A trailing wild card is added to each token in the search text.
- The literal property part (without the wild cards) of the query is boosted by 50. This gives a literal match priority.
Parsing is done with the following analyzer:
literal_propertyValue - Uses our custom literal analyzer. This literal analyzer uses Lucene's WhitespaceTokenizer with Lucene's LowerCaseFilter.
Example of use:
The following examples are based on the Automobiles coding scheme.
Example 1:
Search string: a^s
Lucene query: +literal_propertyValue:a^s* literal_propertyValue:a\^s^50.0
Result: 1 result
- entity code: SpecialCharactersConcept
- entity description: Concept containing special characters
Example 2:
Search string: a^s sp*cial co{nce]pt
Lucene query: +(+literal_propertyValue:a^s* +literal_propertyValue:sp*cial* +literal_propertyValue:co{nce]pt*) ((+literal_propertyValue:a\^s +literal_propertyValue:sp\*cial +literal_propertyValue:co\{nce\]pt)^50.0)
Result: 1 result
- entity code: SpecialCharactersConcept
- entity description: Concept containing special characters
Associated JUnits:
Junit tests can be found here: https://github.com/lexevs/lexevs/blob/master/lbTest/src/test/java/org/LexGrid/LexBIG/Impl/function/query/lucene/searchAlgorithms/TestLiteralContains.java
