server.enqueue(
      MockResponse.Builder()
        .addHeader("Etag", "a")
        .addHeader("Cache-Control: max-age=0")
        .addHeader("A: a1")
        .addHeader("B: b2")
        .addHeader("B: b3")
        .body("abcd")
        .build(),
    )
    server.enqueue(
      MockResponse.Builder()
        .code(HttpURLConnection.HTTP_NOT_MODIFIED)
        .addHeader("B: b4")

</p>

<pre>
type (
	A1 = string
	A2 = A1
)

type (
	B1 string
	B2 B1
	B3 []B1
	B4 B3
)
</pre>

<p>
The underlying type of <code>string</code>, <code>A1</code>, <code>A2</code>, <code>B1</code>,
and <code>B2</code> is <code>string</code>.
The underlying type of <code>[]B1</code>, <code>B3</code>, and <code>B4</code> is <code>[]B1</code>.
</p>

<h3 id="Method_sets">Method sets</h3>
<p>