Assert.java

import static org.junit.Assert.assertEquals;

import java.lang.reflect.Method;

import org.hamcrest.Matcher;
import org.hamcrest.MatcherAssert;

import net.sf.cglib.proxy.Enhancer;
import net.sf.cglib.proxy.InvocationHandler;

public class Assert {

  public static  void assertThat(T actual,
                                    Matcher matcher) {
    MatcherAssert.assertThat(actual, matcher);
  }

  public static  T assertThat(T object) {
    return assertThat(object, true);
  }

  public static  T assertThatNot(T object) {
    return assertThat(object, false);
  }

  private static  T assertThat(final T object,
                                  final boolean value) {
    Enhancer enhancer = new Enhancer();
    enhancer.setSuperclass(object.getClass());
    enhancer.setCallback(new InvocationHandler() {
      @Override
      public Object invoke(Object proxy,
                           Method method,
                           Object[] args) throws Throwable {
        if (method.getReturnType() != Boolean.TYPE) {
           throw new IllegalStateException(
             "Wrong usage of assertThat for method "
             + method.getName()
             + ". Please use with boolean methods only");
        }
        boolean result
          = (Boolean)method.invoke(object, args);
        assertEquals("result of method "
          + method.getName(), value, result);
        return result;
      }
    });
    return (T) enhancer.create();
  }
}