Groovy way to dynamically invoke a Class

Question

I know in Groovy you can invoke a method on a class/object using a string. For example:

Foo."get"(1)
  /* or */
String meth = "get"
Foo."$meth"(1)

Is there a way to do this with the class? I have the name of the class as a string and would like to be able to dynamically invoke that class. For example, looking to do something like:

String clazz = "Foo"
"$clazz".get(1)

I think I'm missing something really obvious, just am not able to figure it out.

Thanks.

Answer 1

Try this:

def cl = Class.forName("org.package.Foo")
cl.get(1)

A little bit longer but should work.

If you want to create "switch"-like code for static methods, I suggest to instantiate the classes (even if they have only static methods) and save the instances in a map. You can then use

map[name].get(1)

to select one of them.

[EDIT] "$name" is a GString and as such a valid statement. "$name".foo() means "call the method foo() of the class GString.

Answer 2

As suggested by Guillaume Laforge on Groovy ML,

("Foo" as Class).get(i)

would give the same result.

I've tested with this code:

def name = "java.lang.Integer"
def s = ("$name" as Class).parseInt("10")
println s

Answer 3

Here's another way

import org.codehaus.groovy.grails.commons.ApplicationHolder as AH

def target = application.domainClasses.find{it.name == 'ClassName'}
target.clazz.invokeMethod("Method",args)

With this you don't need to specify the package name. Be careful though if you have the same class name in two different packages.