Two maven project, project A load the project B jar, create the object dynamically and invoke the method
Project A:
public interface MyInterface {
public void play();
}
Project A:
package hk.quantr.projectb;
import java.io.IOException;
import java.io.InputStream;
import java.net.URL;
import java.net.URLClassLoader;
import java.nio.file.Paths;
import java.util.Enumeration;
import java.util.jar.JarEntry;
import java.util.jar.JarFile;
import org.apache.commons.io.IOUtils;
public class ProjectB {
public static void main(String[] args) throws IOException, ClassNotFoundException, InstantiationException, IllegalAccessException {
String jarPath = Paths.get("../projectA/target/projectA-1.0.jar").toString();
JarFile jarFile = new JarFile(jarPath);
Enumeration<JarEntry> e = jarFile.entries();
URL[] urls = {new URL("jar:file:" + jarPath + "!/")};
URLClassLoader cl = URLClassLoader.newInstance(urls);
while (e.hasMoreElements()) {
JarEntry je = e.nextElement();
System.out.println(">" + je);
if (je.getName().equals("META-INF/MANIFEST.MF")) {
InputStream input = jarFile.getInputStream(je);
String content = IOUtils.toString(input, "utf-8");
System.out.println(content);
}
if (je.getName().equals("component.xml")) {
System.out.println("-".repeat(100));
InputStream input = jarFile.getInputStream(je);
String content = IOUtils.toString(input, "utf-8");
System.out.println(content);
System.out.println("-".repeat(100));
}
if (je.isDirectory() || !je.getName().endsWith(".class")) {
continue;
}
String className = je.getName().substring(0, je.getName().length() - 6);
className = className.replace('/', '.');
Class c = cl.loadClass(className);
MyInterface clsInstance = (MyInterface) c.newInstance();
clsInstance.play();
}
}
}
Project B:
public class Project2 implements MyInterface {
@Override
public void play() {
System.out.println("play project 2");
}
}