Метод findClasses из нашего ClassLoaderUtil может быть хорошей отправной точкой для адаптации к вашим потребностям.
public class ClassLoaderUtil {
/**
* Recursive method used to find all classes in a given path (directory or zip file url). Directories
* are searched recursively. (zip files are
* Adapted from http://snippets.dzone.com/posts/show/4831 and extended to support use of JAR files
*
* @param path The base directory or url from which to search.
* @param packageName The package name for classes found inside the base directory
* @param regex an optional class name pattern. e.g. .*Test
* @return The classes
*/
private static TreeSet<String> findClasses(String path, String packageName, Pattern regex) throws Exception {
TreeSet<String> classes = new TreeSet<String>();
if (path.startsWith("file:") && path.contains("!")) {
String[] split = path.split("!");
URL jar = new URL(split[0]);
ZipInputStream zip = new ZipInputStream(jar.openStream());
ZipEntry entry;
while ((entry = zip.getNextEntry()) != null) {
if (entry.getName().endsWith(".class")) {
String className = entry.getName().replaceAll("[$].*", "").replaceAll("[.]class", "").replace('/', '.');
if (className.startsWith(packageName) && (regex == null || regex.matcher(className).matches()))
classes.add(className);
}
}
}
File dir = new File(path);
if (!dir.exists()) {
return classes;
}
File[] files = dir.listFiles();
for (File file : files) {
if (file.isDirectory()) {
assert !file.getName().contains(".");
classes.addAll(findClasses(file.getAbsolutePath(), packageName + "." + file.getName(), regex));
} else if (file.getName().endsWith(".class")) {
String className = packageName + '.' + file.getName().substring(0, file.getName().length() - 6);
if (regex == null || regex.matcher(className).matches())
classes.add(className);
}
}
return classes;
}
public static <T> List<T> instances(Class<? extends T>[] classList) {
List<T> tList = new LinkedList<T>();
for(Class<? extends T> tClass : classList) {
try {
// Only try to instantiate real classes.
if(! Modifier.isAbstract(tClass.getModifiers()) && ! Modifier.isInterface(tClass.getModifiers())) {
tList.add(tClass.newInstance());
}
} catch (Throwable t) {
throw new RuntimeException(t.getMessage(), t);
}
}
return tList;
}
public static Class[] findByPackage(String packageName, Class isAssignableFrom) {
Class[] clazzes = getClassesInPackage(packageName, null);
if(isAssignableFrom == null) {
return clazzes;
} else {
List<Class> filteredList = new ArrayList<Class>();
for(Class clazz : clazzes) {
if(isAssignableFrom.isAssignableFrom(clazz))
filteredList.add(clazz);
}
return filteredList.toArray(new Class[0]);
}
}
/**
* Scans all classes accessible from the context class loader which belong to the given package and subpackages.
* Adapted from http://snippets.dzone.com/posts/show/4831 and extended to support use of JAR files
*
* @param packageName The base package
* @param regexFilter an optional class name pattern.
* @return The classes
*/
public static Class[] getClassesInPackage(String packageName, String regexFilter) {
Pattern regex = null;
if (regexFilter != null)
regex = Pattern.compile(regexFilter);
try {
ClassLoader classLoader = Thread.currentThread().getContextClassLoader();
assert classLoader != null;
String path = packageName.replace('.', '/');
Enumeration<URL> resources = classLoader.getResources(path);
List<String> dirs = new ArrayList<String>();
while (resources.hasMoreElements()) {
URL resource = resources.nextElement();
dirs.add(resource.getFile());
}
TreeSet<String> classes = new TreeSet<String>();
for (String directory : dirs) {
classes.addAll(findClasses(directory, packageName, regex));
}
ArrayList<Class> classList = new ArrayList<Class>();
for (String clazz : classes) {
classList.add(Class.forName(clazz));
}
return classList.toArray(new Class[classes.size()]);
} catch (Exception e) {
e.printStackTrace();
return null;
}
}
}