public class ClassLoadTest {

    public void test() {
        // 外部 jar 所在位置
        String path = "file:C:\\Users\\Boomni_Sun\\Desktop\\chinadaas-magic-api-0.3.1-SNAPSHOT.jar";
        URLClassLoader urlClassLoader = null;
        try {
            // 通过URLClassLoader加载外部jar
            urlClassLoader = new URLClassLoader(new URL[]{new URL(path)});
            Class<?> cls = Class.forName("com.chinadaas.magic.api.utils.MyTest", false, urlClassLoader);
            Object instance = cls.newInstance();
        } catch (Exception e) {
            e.printStackTrace();
        } finally {
            // 卸载关闭外部jar
            try {
                urlClassLoader.close();
            } catch (IOException e) {
                System.out.println("关闭外部jar失败：" + e.getMessage());
            }
        }
    }
}