newInstance even if the class object specified represent of anonymous class.

gistfile1.txt

package com.github.tauty.rufa;

import java.lang.reflect.Constructor;
import java.lang.reflect.InvocationTargetException;

public class Util {

	public static <T> T newInstance(Class<T> clazz) {
		try {
			return generate(getConstructor(clazz));
		} catch (NoSuchMethodException ignore) {
		}
		try {
			Class<?> enclosingClass = clazz.getEnclosingClass();
			return generate(getConstructor(clazz, enclosingClass),
					newInstance(enclosingClass));
		} catch (NoSuchMethodException e) {
			throw new IllegalArgumentException("The class, '" + clazz.getName()
					+ "', must have default constructor.", e);
		}
	}

	private static <T> Constructor<T> getConstructor(Class<T> clazz,
			Class<?>... paramClasses) throws NoSuchMethodException {
		try {
			return clazz.getDeclaredConstructor(paramClasses);
		} catch (SecurityException e) {
			throw new WrapException(e);
		}
	}

	private static <T> T generate(Constructor<T> c, Object... params) {
		try {
			boolean accessible = c.isAccessible();
			c.setAccessible(true);
			T instance = c.newInstance(params);
			c.setAccessible(accessible);
			return instance;
		} catch (SecurityException e) {
			throw new WrapException(e);
		} catch (InstantiationException e) {
			throw new WrapException(e);
		} catch (IllegalAccessException e) {
			throw new WrapException(e);
		} catch (IllegalArgumentException e) {
			throw new WrapException(e);
		} catch (InvocationTargetException e) {
			throw new WrapException(e);
		}
	}

	public static void main(String[] args) {
		System.out.println(newInstance(StaticInner.class));
		System.out.println(newInstance(Inner.class));
		Runnable runnable = new Runnable() {

			public void run() {
				Runnable executor = new Runnable() {

					public void run() {
					}
				};
				System.out.println(newInstance(executor.getClass()));
			}
		};
		System.out.println(newInstance(runnable.getClass()));
		runnable.run();
	}

	private static class StaticInner {
	}

	private class Inner {
	}

}