Groovy Module Extension

CustomMethods.groovy

package br.com.soeirosantos

import java.text.SimpleDateFormat

class CustomMethods {
	
    static isNotBlank(String self) { 
        !self.trim().isEmpty()	
    }
	
    static toShortFormat(Date self) {
        self.format("dd/MM/yyyy")
    }
	
    static toHeaderFormat(Date self, String city) {
        def dateFormat = new SimpleDateFormat("dd 'de' MMMMM 'de' yyyy", new Locale("pt") ).format(self)
        "$city, $dateFormat."
    }

    static toString(ArrayList self) {
        self.join(", ")
    }
		
}

org.codehaus.groovy.runtime.ExtensionModule

moduleName=util-module
moduleVersion=1.0
extensionClasses=br.com.soeirosantos.CustomMethods

UtilTest.groovy

package br.com.soeirosantos

import org.junit.Test;

class UtilTest {

        @Test
        public void test() {

        assert "foo".isNotBlank()

        assert ! "  ".isNotBlank()

        def dt = new Date(1377614221138)

        assert  "27/08/2013" == dt.toShortFormat()

        assert "Niterói, 27 de Agosto de 2013." == dt.toHeaderFormat("Niterói")

        assert "1, 2, 3, 4, 5" == [1, 2, 3, 4, 5].toString()  

    }
}