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java - How to retrieve Enum name using the id?

I have the enum as:

public enum EnumStatus {

    PASSED(40L, "Has Passed"),
    AVERAGE(60L, "Has Average Marks"),
    GOOD(80L, "Has Good Marks");

    private java.lang.String name;

    private java.lang.Long id;

    EnumStatus(Long id, java.lang.String name) {
        this.name = name;
        this.id = id;
    }

    public java.lang.String getName() {
        return name;
    }

    public java.lang.Long getId() {
        return id;
    }
}

I have to get the Enum names(PASSED, AVERAGE, GOOD) using the ids only(40,60, 80). How do I do it?

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by (71.8m points)

Create a static method in your enum which searches in values (implicit method/member, don't know exactly which is it) and returns the corresponding value. For cases in which the method can not find a matching value, you should create a special entry, e.g. UNKNOWN, which you can return. This way, you do not have to return null, which is always a bad idea.

public static EnumStatus getById(Long id) {
    for(EnumStatus e : values()) {
        if(e.id.equals(id)) return e;
    }
    return UNKNOWN;
}

Btw - your code seems to be wrong. The bracket after GOOD seems to not belong there.


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