/**
 * Checks if object has proper toString defined. This matcher can be
 * replaced with JUnit 4.8
 */
public static Matcher<Object> hasToString() {
    return new TypeSafeMatcher<Object>() {

        @Override
        public boolean matchesSafely(Object objectToTest) {
            try {
                objectToTest.getClass().getDeclaredMethod("toString");
            } catch (Exception e) {
                return false;
            }
            String s = objectToTest.toString();
            if (s == null || s.length() == 0) {
                return false;
            }
            return true;
        }

        @Override
        public void describeTo(Description description) {
            description.appendText("proper toString()");
        }

    };
}
 

/**
 * Checks if array is non-empty. This matcher can be replaced with JUnit 4.8
 */
public static Matcher<Object[]> hasItemInArray() {
    return new TypeSafeMatcher<Object[]>() {

        @Override
        public boolean matchesSafely(Object[] arrayToTest) {
            if (arrayToTest == null || arrayToTest.length == 0) {
                return false;
            }
            return true;
        }

        @Override
        public void describeTo(Description description) {
            description.appendText("non-empty array");
        }

    };
}
 

/**
 * Checks if list is non-empty. This matcher can be replaced with JUnit 4.8
 */
public static Matcher<Collection<?>> hasItems() {
    return new TypeSafeMatcher<Collection<?>>() {

        @Override
        public boolean matchesSafely(Collection<?> collection) {
            if (collection == null || collection.isEmpty()) {
                return false;
            }
            return true;
        }

        @Override
        public void describeTo(Description description) {
            description.appendText("non-empty list");
        }

    };
}
 

/**
 * Checks if collection has the given number of items.
 */
public static Matcher<Collection<?>> hasItems(final int numberOfItems) {
    return new TypeSafeMatcher<Collection<?>>() {

        @Override
        public boolean matchesSafely(Collection<?> collection) {
            if (collection == null || collection.size() != numberOfItems) {
                return false;
            }
            return true;
        }

        @Override
        public void describeTo(Description description) {
            description.appendText("expected a collection with "
                    + numberOfItems + " items");
        }

    };
}
 

private static Matcher<UntypedResultSet.Row> withElements(final int key, final String v1, final int v2) {
    return new TypeSafeMatcher<UntypedResultSet.Row>()
    {
        @Override
        public boolean matchesSafely(Row input)
        {
            if (!input.has("k") || !input.has("v1") || !input.has("v2"))
                return false;
            return input.getInt("k") == key
                    && input.getString("v1").equals(v1)
                    && input.getInt("v2") == v2;
        }

        @Override
        public void describeTo(Description description)
        {
            description.appendText(String.format("a row containing: %s, %s, %s", key, v1, v2));
        }
    };
    
}