### Question:
HasHeaderWithValue extends TypeSafeMatcher<Response> { @Override public void describeTo(Description description) { description.appendText("Response with header named '" + name + "' and value matching: "); valueMatcher.describeTo(description); } HasHeaderWithValue(String name, Matcher<String> valueMatcher); @Override void describeTo(Description description);  }### Answer:
@Test public void matcherShouldDescribeItselfCorrectly() { Description description = new StringDescription(); matcher.describeTo(description); assertThat(description.toString(), is("Response with header named 'Content-Type' and value matching: a string containing \"application/json\"")); }