Uppercase token filter
Changes token text to uppercase. For example, you can use theuppercase filter to changethe Lazy DoG toTHE LAZY DOG.
This filter uses Lucene’sUpperCaseFilter.
Warning
Depending on the language, an uppercase character can map to multiple lowercase characters. Using theuppercase filter could result in the loss of lowercase character information.
To avoid this loss but still have a consistent letter case, use thelowercase filter instead.
The followinganalyze API request uses the defaultuppercase filter to change thethe Quick FoX JUMPs to uppercase:
GET _analyze{ "tokenizer" : "standard", "filter" : ["uppercase"], "text" : "the Quick FoX JUMPs"}
The filter produces the following tokens:
[ THE, QUICK, FOX, JUMPS ]The followingcreate index API request uses theuppercase filter to configure a newcustom analyzer.
PUT uppercase_example{ "settings": { "analysis": { "analyzer": { "whitespace_uppercase": { "tokenizer": "whitespace", "filter": [ "uppercase" ] } } } }}