Function送る

MyApplication.java

//サーバ側　　
import java.io.File;
import java.net.URL;
import java.net.URLClassLoader;
import java.nio.file.Files;
import java.nio.file.StandardCopyOption;
import java.util.function.Function;

import javax.servlet.ServletInputStream;

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.PostMapping;
import org.springframework.web.bind.annotation.RestController;

@SpringBootApplication
public class MyApplication {

	public static void main(String[] args) {
		SpringApplication.run(MyApplication.class, args);
	}

	@RestController
	public class IndexController {
		@PostMapping("/invoke/{functionName}")
		public int invoke(ServletInputStream is, @PathVariable String functionName) throws Exception {
			File classDir = new File("myclasses");
			File classFile = new File(classDir, functionName.replace(".", "/") + ".class");
			classFile.getParentFile().mkdirs();
			Files.copy(is, classFile.toPath(), StandardCopyOption.REPLACE_EXISTING);
			URLClassLoader classLoader = new URLClassLoader(new URL[] { classDir.toURI().toURL() });
			int variable = 100;
			return (Integer) ((Function) classLoader.loadClass(functionName).newInstance()).apply(variable);
		}
	}
}

MyClient.java

//クライアント側
import java.io.ByteArrayOutputStream;
import java.net.URL;

import org.apache.tomcat.util.http.fileupload.IOUtils;
import org.springframework.http.ResponseEntity;
import org.springframework.web.client.RestTemplate;

public class MyClient {

	public static void main(String[] args) throws Exception {
		Class<?> targetClass = MyFunction2.class;
		String classFile = targetClass.getName().replace(".", "/").concat(".class");
		RestTemplate rest = new RestTemplate();
		URL classFileLocation = new URL(
				targetClass.getProtectionDomain().getCodeSource().getLocation().toExternalForm() + classFile);
		ByteArrayOutputStream bout = new ByteArrayOutputStream();
		IOUtils.copy(classFileLocation.openStream(), bout);
		ResponseEntity<Integer> postForEntity = rest.postForEntity(
				"http://localhost:8080/invoke/" + targetClass.getName(), bout.toByteArray(), Integer.class);
		System.out.println(postForEntity.getBody());//足し算の結果
	}
}

MyFunction.java

//関数
import java.util.function.Function;

public class MyFunction implements Function<Integer, Integer> {
	@Override
	public Integer apply(Integer t) {
		return t + 100;
	}

}