Is there a way to upper case a JSON value before binding it - using SpringBoot?

Question

I am working on a SpringBoot REST service. The REST service works when the UI sends the right JSON values (formatted).

Sometimes the UI team will forget to upper case a property value and cause an exception. I want to make the REST service handle such cases.

JSON property is being POSTed as

"category":"patient"

It is supposed to be POSTed with uppercase.

"category":"PATIENT"

The Java object property category is a ENUM

public enum StaffCategory {
    PATIENT, EQUIPMENT
}

The ui model object

@JsonProperty("category")
private StaffCategory category;

@JsonProperty("category")
public StaffCategory getCategory() {
    return category;
}

@JsonProperty("category")
public void setCategory(StaffCategory category) {
    this.category = category;
}

@JsonProperty("category")
private StaffCategory category;

This is the error I get

    Can not deserialize value of type model.constants.StaffCategory 
from String "patient": value not one of declared Enum instance names: [PATIENT, EQUIPMENT]

Answer 1

Although UI team should stick to backend API specs, still you can use ObjectMapper configuration to overcome this specific scenario:

@Bean
public ObjectMapper objectMapper() {
    ObjectMapper mapper = new ObjectMapper();
    mapper.configure(MapperFeature.ACCEPT_CASE_INSENSITIVE_ENUMS, true);
    return mapper;
}

Answer 2

You dont need to convert it to uppercase because it lowers readability and also avoids maintainability.You only need to change your Enum definition as:

public enum StaffCategory {
    PATIENT("patient"), EQUIPMENT("equipment");

    private String value;
    private StaffCategory(String value) { this.value = value; }

    @JsonValue
    public String getValue() { return this.value; }
}

This way it get easily deserialized with no breaking your code or facing any problems.