Java Enum | Created map in constructor | But cannot access/send its value

Created map in enum using parameters

Key: AUTQ – Value: AUTP
Key: FAUQ – Value: FAUP

I created map but now stuck in static and non static calls within enum

AUTHOR("AUTQ","AUTP"), <--- Author is of no use but the values AUTQ is Key and AUTP is value
FINA("FAUQ","FAUP"),

private final Map<String, String> val;
MessageFunction(String key, String value){
    this.val = new HashMap<>();
    this.val.put(key.toUpperCase(), value); <--- Created a Map
}

public static String getResultValue( String fromValue) {
   
    return this.val.get(fromValue.toUpperCase()); <--- How to access it?
}

When i add static then it do not allow to call this.val (Can not be referred from static context)

When i add non static then not sure how to call it in code.

Could you please suggest how to handle this use case?

>Solution :

You can create the map contents in a static block.

public enum MessageFunction {
    AUTHOR("AUTQ", "AUTP"),
    FINA("FAUQ", "FAUP");

    private static final Map<String, String> val;

    static {
        val = Arrays.stream(MessageFunction.values())
                .collect(Collectors.toMap(my -> my.key.toUpperCase(), my -> my.value));
    }

    MessageFunction(String key, String value) {
        this.key = key;
        this.value = value;
    }

    private final String key;
    private final String value;

    public static String getResultValue(String fromValue) {
        return val.get(fromValue.toUpperCase());
    }
}

Both the below calls print AUTP.

System.out.println(MessageFunction.getResultValue("AUTQ"));
System.out.println(MessageFunction.getResultValue("autq"));