How to load and use one more than .class file?

Question

I have a folder in this folder I have 4 .class file .I want load this files in my main program and call the methods .for one .class file I do like so:

File file = new File("/home/saeed/NetBeansProjects/java-test/build/classes");

URI uri = file.toURI();
URL[] urls = new URL[]{uri.toURL()};

ClassLoader classLoader = new URLClassLoader(urls);

Class clazz = classLoader.loadClass("com.test.NewClass");

And for invoke the method I do like so:

Object obj = clazz.newInstance();

System.out.println(""+obj.getClass().
        getMethod("echo",String.class).invoke(obj, "Saeed"));

Now I have one more than .class in the folder .How can I load and invoke their methods? Can anyone help me?

Um...do the same thing three more times? Or better yet, put that directory in your classpath and use them normally? What's the question here exactly? — T.J. Crowder, Aug 30 '15 at 07:46
That question doesn't make any sense. What are you actually trying to do? If you're just trying to use class files in the normal way, you don't use a classloader directly at all. See: https://docs.oracle.com/javase/tutorial/essential/environment/paths.html — T.J. Crowder, Aug 30 '15 at 07:55
@marzie, we do not understand why you use reflection to load these classes? why not put the folder in classpath? and if you insist on using reflection, the obvious answer is to copy-paste `loadClass` with `clazz1` `clazz2` etc — Sharon Ben Asher, Aug 30 '15 at 07:56
I insist on using reflection .I know how to load one .class file but in my folder there is 4 .class file .How do I load all of them? — marzie, Aug 30 '15 at 07:59
possible duplicate of [Can you find all classes in a package using reflection?](http://stackoverflow.com/questions/520328/can-you-find-all-classes-in-a-package-using-reflection) — Limnic, Aug 30 '15 at 08:22

score 0 · Answer 1 · edited Aug 30 '15 at 08:47

You can use PathMatcher, here is an example:

Path startDir = Paths.get("C:\\home");

String pattern = "*.class";

FileSystem fs = FileSystems.getDefault();
final PathMatcher matcher = fs.getPathMatcher("glob:" + pattern);

FileVisitor<Path> matcherVisitor = new SimpleFileVisitor<Path>() {
    @Override
    public FileVisitResult visitFile(Path file, BasicFileAttributes attribs) {
        Path name = file.getFileName();
        if (matcher.matches(name)) {
            // Found a .class file 
            System.out.print(String.format("Found matched file: '%s'.%n", file));
        }
        return FileVisitResult.CONTINUE;
    }
};

How to load and use one more than .class file?

1 Answers1