Extended Enums usage

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Extended Enums usage

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Since the re-launch of extended enums I'm paying attention in my everyday coding (yes I still write code :) if extended enums will help me.
Here are 2 new examples:

1) I found out that most of the time the name() of the enum is not what I need. I need it to map an XML or HTML tag, an external ID, an entry name in excel or simple type name in a JSON object. So I write something like:

    public enum ConfigName {

        private final String xmlKey;

        LdapConfig(String xmlKey) {
            this.xmlKey = xmlKey;

        public String getXmlKey() {
            return xmlKey;

I could remove the getter, and the IDE helping a lot writing the boiler plate code but why? Here is how it should look:

    public enum ConfigName extends AlternateEnumKey {

The extra feature here is that the name() of the enum (ALL, INTERNAL, OR) is a constant that is not recognized as such by the javac compiler. So:

    @XmlTag(tag = ConfigName.ALL)

will not compile and so:

    @XmlTag(tag = ConfigName.ALL.xmlKey)

will for sure not.

But with extended enum you'll have:

    public @interface XmlTag { AlternateEnumKey tag(); }

    // The framework managing XmlTag will take the alternate key value
    @XmlTag(tag = ConfigName.ALL)

2) Since extended enums also supports generics for enums, and I just have this issue associating also a long (ID) to an enums, you can now write:

    public enum ConfigName extends EnumPairExtension<Long, String> {
        ALL(45L, "local-all"),
        INTERNAL(56L, "local-int"),
        OR(98L, "local-int-ext");

    assert ConfigName.OR.a == 98L;

With this, parsing definitions are a lot cleaner to write.

From http://freddy33.blogspot.com/2011/07/extended-enums-usage.html


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