if (!response.isSuccessful()) throw new IOException("Unexpected code " + response);

          System.out.println(response.body().string());
        }
      }
    ```

### Posting form parameters ([.kt][PostFormKotlin], [.java][PostFormJava])

Use `FormBody.Builder` to build a request body that works like an HTML `<form>` tag. Names and values will be encoded using an HTML-compatible form URL encoding.

    assertEquals("utf-8", mediaType.parameter("charset"))
    assertEquals("1", mediaType.parameter("a"))
    assertEquals("2", mediaType.parameter("b"))
    assertEquals("3", mediaType.parameter("c"))
    assertEquals("utf-8", mediaType.parameter("CHARSET"))
    assertEquals("1", mediaType.parameter("A"))
    assertEquals("2", mediaType.parameter("B"))
    assertEquals("3", mediaType.parameter("C"))
  }

    val charset = parameter("charset") ?: return defaultValue
    return try {
      Charset.forName(charset)
    } catch (_: IllegalArgumentException) {
      defaultValue // This charset is invalid or unsupported. Give up.
    }
  }

  /**
   * Returns the parameter [name] of this media type, or null if this media type does not define
   * such a parameter.
   */

 * modern 4.0.x kotlin source-compatibility.
 */
@Suppress(
  "ASSIGNED_BUT_NEVER_ACCESSED_VARIABLE",
  "UNUSED_ANONYMOUS_PARAMETER",
  "UNUSED_VALUE",
  "UNUSED_VARIABLE",
  "VARIABLE_WITH_REDUNDANT_INITIALIZER",
  "RedundantLambdaArrow",
  "RedundantExplicitType",
  "IMPLICIT_NOTHING_AS_TYPE_PARAMETER",
)
class KotlinSourceModernTest {
  @Test @Ignore
  fun dispatcherFromMockWebServer() {
    val dispatcher =

  }

  @Test
  fun kotlinReifiedTag() {
    val uuidTag = "1234"
    val request =
      Request.Builder()
        .url("https://square.com")
        .tag<String>(uuidTag) // Use the type parameter.
        .build()
    assertThat(request.tag<String>()).isSameAs("1234")
    assertThat(request.tag<Any>()).isNull()

    // Alternate access APIs also work.