How to force Jackson deserialize field values to lower case - spring

Question

I have spring application which expose REST endpoint, lets name it "doAction". As the request it consumes object:
class Person{
private String name;
private String email;
}
Some clients can call this endpoint by passing data with different practice of writing words, like:
Peter_1
name = Peter
email = peter#gmail.com (lower case)
Mark_2
name = mark
email = MARK#gmail.com (upper case)
Julia_3
name = julia
email = JuliaToward#gmail.com (camel case)
Is there some approach to force all income data be parsed to lowercase(lets assume all fields are Strings)?
So as a result I desire to have:
Peter_1
name = peter
email = peter#gmail.com
Mark_2
name = mark
email = mark#gmail.com
Julia_3
name = julia
email = juliatoward#gmail.com
Solution for Jackson is appreciated.

Answer 1

Short answer Call toLower in the setter
Here is an example:
class Animal
{
private String name;
public void setName(final String newValue)
{
StringUtils.trimToNull(StringUtils.lowerCase(newValue));
}
}
I also recommend either trimToNUll or trimToEmpty.

Answer 2

If you are using Spring Data Rest with spring mvc and you want all incoming string data to be in lower case then define following
public class StringSerializer extends StdDeserializer<String>{
public StringSerializer() {
this(null);
}
public StringSerializer(Class<String> vc) {
super(vc);
}
#Override
public String deserialize(JsonParser p, DeserializationContext ctxt) throws IOException, JsonProcessingException {
JsonToken t = p.getCurrentToken();
if (t==JsonToken.VALUE_STRING){
String receivedValue = p.getText();
if (receivedValue == null)
return null;
else
return receivedValue.toLowerCase();
}else{
return null;
}
}
}
And following:
#Configuration
public class RestDataConfig extends RepositoryRestMvcConfiguration {
#Override
#Bean
public ObjectMapper halObjectMapper() {
ObjectMapper mapper = super.halObjectMapper();
SimpleModule module = new SimpleModule();
module.addDeserializer(String.class, new StringSerializer());
mapper.registerModule(module);
return mapper;
}
}