Java: String to Enum

Getting Enum Values from Strings in Java (Spring Boot Compatible)

Java doesn't directly support string-to-enum conversion. However, several approaches efficiently handle this. For Spring Boot applications, leveraging @JsonValue offers a clean solution.

Method 1: Using Enum.valueOf() (Simple, but error-prone)

enum Status { ACTIVE, INACTIVE }

Status status = Status.valueOf("ACTIVE"); //Throws IllegalArgumentException if "ACTIVE" doesn't exist

This is concise but throws IllegalArgumentException if the string doesn't match an enum constant. Robust error handling is crucial.

Method 2: Using a Helper Method (More Robust)

enum Status { ACTIVE, INACTIVE }

public static Status fromString(String text) {
    for (Status b : Status.values()) {
        if (b.name().equalsIgnoreCase(text)) {
            return b;
        }
    }
    return null; //Or throw exception
}

This iterates through enum values, offering case-insensitive matching and a controlled null return (or custom exception).

Method 3: Using @JsonValue (Spring Boot Elegance)

import com.fasterxml.jackson.annotation.JsonValue;

enum Status {
    ACTIVE("active"), INACTIVE("inactive");

    private final String value;

    Status(String value) {
        this.value = value;
    }

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

    public static Status fromValue(String value) {
        for (Status status : Status.values()) {
            if (status.value.equals(value)) {
                return status;
            }
        }
        return null; //Or throw exception
    }
}

@JsonValue helps with JSON serialization/deserialization; fromValue provides robust string-to-enum conversion. This is ideal for REST APIs in Spring Boot. Remember to include Jackson dependency: com.fasterxml.jackson.core:jackson-databind.

Choose the method best fitting your needs and error handling preferences. Method 2 and 3 are recommended for production code due to their robustness. Consider adding custom exceptions for improved error reporting.