Example for defining a refreshable Groovy Script in Spring Boot with Java Config - at least thats the current state of affairs :)

App.java

package demo;

import java.util.concurrent.TimeUnit;

import org.springframework.aop.TargetSource;
import org.springframework.aop.framework.ProxyFactory;
import org.springframework.aop.support.DelegatingIntroductionInterceptor;
import org.springframework.beans.factory.BeanFactory;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.context.annotation.Bean;
import org.springframework.core.io.ClassPathResource;
import org.springframework.scripting.groovy.GroovyScriptFactory;
import org.springframework.scripting.support.RefreshableScriptTargetSource;
import org.springframework.scripting.support.ResourceScriptSource;

@SpringBootApplication
public class App {

	public static void main(String[] args) throws Exception{

		Evaluator evaluator = SpringApplication.run(App.class, args).getBean("evaluator", Evaluator.class);

		for (int i = 0; i < 20; i++) {

			System.out.printf("evaluated to %s%n", evaluator.evaluate(null));

			TimeUnit.SECONDS.sleep(1);
		}
	}

	@Bean
	public Evaluator evaluator(BeanFactory beanFactory) throws Exception {

		GroovyScriptFactory factory = new GroovyScriptFactory("classpath");
		factory.setBeanFactory(beanFactory);

		ResourceScriptSource script = new ResourceScriptSource(new ClassPathResource("GroovyEvaluator.groovy"));

		RefreshableScriptTargetSource rsts = new RefreshableScriptTargetSource(beanFactory, "ignored-bean-name", factory, script, false) {

			@Override
			protected Object obtainFreshBean(BeanFactory beanFactory, String beanName) {
				
				/*
				 * we ask the factory to create a new script bean directly instead
				 * asking the beanFactory for simplicity. 
				 */
				try {
					return factory.getScriptedObject(script);
				} catch (Exception e) {
					throw new RuntimeException(e);
				}
			}
		};
		rsts.setRefreshCheckDelay(1000L);

		ProxyFactory proxyFactory = new ProxyFactory();
		proxyFactory.setTargetSource(rsts);
		proxyFactory.setInterfaces(Evaluator.class);

		DelegatingIntroductionInterceptor introduction = new DelegatingIntroductionInterceptor(rsts);
		introduction.suppressInterface(TargetSource.class);
		proxyFactory.addAdvice(introduction);

		return (Evaluator) proxyFactory.getProxy();
	}
}

Evaluator.java

package demo;

public interface Evaluator {

	boolean evaluate(Object arg);
}

GroovyEvaluator.groovy

class GroovyEvaluator implements demo.Evaluator{

	def boolean evaluate(arg) {
		return true;
	}
}

pom.xml

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
	xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
	<modelVersion>4.0.0</modelVersion>

	<groupId>demo</groupId>
	<artifactId>spring-boot-groovy-reloading-demo</artifactId>
	<version>0.0.1-SNAPSHOT</version>
	<packaging>jar</packaging>

	<name>spring-boot-groovy-reloading-demo</name>
	<description>Demo project for Groovy reloading Spring Boot</description>

	<parent>
		<groupId>org.springframework.boot</groupId>
		<artifactId>spring-boot-starter-parent</artifactId>
		<version>1.3.0.M5</version>
		<relativePath /> <!-- lookup parent from repository -->
	</parent>

	<properties>
		<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
		<java.version>1.8</java.version>
	</properties>

	<dependencies>
		<dependency>
			<groupId>org.springframework.boot</groupId>
			<artifactId>spring-boot-starter-aop</artifactId>
		</dependency>
	
		<dependency>
			<groupId>org.codehaus.groovy</groupId>
			<artifactId>groovy</artifactId>
		</dependency>

		<dependency>
			<groupId>org.springframework.boot</groupId>
			<artifactId>spring-boot-starter-test</artifactId>
			<scope>test</scope>
		</dependency>
	</dependencies>

	<build>
		<plugins>
			<plugin>
				<groupId>org.springframework.boot</groupId>
				<artifactId>spring-boot-maven-plugin</artifactId>
			</plugin>
		</plugins>
	</build>

	<repositories>
		<repository>
			<id>spring-snapshots</id>
			<name>Spring Snapshots</name>
			<url>https://repo.spring.io/snapshot</url>
			<snapshots>
				<enabled>true</enabled>
			</snapshots>
		</repository>
		<repository>
			<id>spring-milestones</id>
			<name>Spring Milestones</name>
			<url>https://repo.spring.io/milestone</url>
			<snapshots>
				<enabled>false</enabled>
			</snapshots>
		</repository>
	</repositories>
	<pluginRepositories>
		<pluginRepository>
			<id>spring-snapshots</id>
			<name>Spring Snapshots</name>
			<url>https://repo.spring.io/snapshot</url>
			<snapshots>
				<enabled>true</enabled>
			</snapshots>
		</pluginRepository>
		<pluginRepository>
			<id>spring-milestones</id>
			<name>Spring Milestones</name>
			<url>https://repo.spring.io/milestone</url>
			<snapshots>
				<enabled>false</enabled>
			</snapshots>
		</pluginRepository>
	</pluginRepositories>

</project>

Would be nice to have a complete maven directory structure - at least in the download zip.

Would be nice to have a complete maven directory structure - at least in the download zip.

You can do it

GroovyEvaluator.groovy should be in the resource folder, FYI