Does Groovy have extension methods like in C#?

问题

Can I add to a method to a final class somehow like in C#?

So I could do something like:

"Some text".myOwnFunction();

Instead of:

MyStaticClass.myOwnFunction("Some text");

回答1:

You can either add it to all future string instances via the metaClass

    String.metaClass.myOwnFunction = {-> delegate.length() }
    assert "Tim".myOwnFunction() == 3

Or you can add it to a single instance

    String a = "Tim"
    a.metaClass.myOwnFunction = {-> delegate.length() }
    assert a.myOwnFunction() == 3

Or you can add these methods when a jar is in the classpath at startup with extension modules

来源：https://stackoverflow.com/questions/36954719/does-groovy-have-extension-methods-like-in-c