# Calls

The HTTP client’s job is to accept your request and produce its response. This is simple in theory but it gets tricky in practice.

## [Requests](https://square.github.io/okhttp/4.x/okhttp/okhttp3/-request/)

Each HTTP request contains a URL, a method (like `GET` or `POST`), and a list of headers. Requests may also contain a body: a data stream of a specific content type.

## [Responses](https://square.github.io/okhttp/4.x/okhttp/okhttp3/-response/)

        byte[] encrypted2 = storage.encryptCredentials(plaintext.clone());

        // Should produce different ciphertexts due to random IV
        assertFalse(Arrays.equals(encrypted1, encrypted2), "Different encryptions should produce different ciphertexts");

        // But both should decrypt to same plaintext
        char[] decrypted1 = storage.decryptCredentials(encrypted1);

 *   <li>Conversion of individual Hankaku Kana characters to Zenkaku Kana characters.</li>
 *   <li>Handling of voiced (ﾞ) and semi-voiced (ﾟ) sound marks to produce the correct Zenkaku Kana characters.</li>
 * </ul>
 *
 * <p>Example usage:</p>
 * <pre>
 * {@code
 * HankakuKanaToZenkakuKana normalizer = new HankakuKanaToZenkakuKana();

            options.addOption(Option.builder(VERBOSE)
                    .longOpt("verbose")
                    .desc("Produce execution verbose output")
                    .get());
            options.addOption(Option.builder(SHOW_ERRORS)
                    .longOpt("errors")
                    .desc("Produce execution error messages")
                    .get());
            options.addOption(Option.builder(BATCH_MODE)

        assertEquals(32, derived3.length, "Derived key should have correct length");

        assertFalse(Arrays.equals(derived1, derived2), "Different labels should produce different keys");
        assertFalse(Arrays.equals(derived1, derived3), "Different contexts should produce different keys");
    }

    @Test
    public void testStoreNullKey() {

<img src="/img/tutorial/response-status-code/image01.png">

/// note

Some response codes (see the next section) indicate that the response does not have a body.

FastAPI knows this, and will produce OpenAPI docs that state there is no response body.

///

## About HTTP status codes { #about-http-status-codes }

/// note

If you already know what HTTP status codes are, skip to the next section.

///

   * {@code node}'s incoming edges <i>against</i> the direction (if any) of the edge.
   *
   * <p>Some algorithms that operate on a {@code PredecessorsFunction} may produce undesired results
   * if the returned {@link Iterable} contains duplicate elements. Implementations of such
   * algorithms should document their behavior in the presence of duplicates.
   *

### 4. Excluded Types

- Already compressed objects are not fit for compression since they do not have compressible patterns.
Such objects do not produce efficient [`LZ compression`](https://en.wikipedia.org/wiki/LZ77_and_LZ78)
which is a fitness factor for a lossless data compression.

Pre-compressed input typically compresses in excess of 2GiB/s per core,

   * {@code node}'s incoming edges <i>against</i> the direction (if any) of the edge.
   *
   * <p>Some algorithms that operate on a {@code PredecessorsFunction} may produce undesired results
   * if the returned {@link Iterable} contains duplicate elements. Implementations of such
   * algorithms should document their behavior in the presence of duplicates.
   *

   * edges". For that functionality, see {@link Graphs#reachableNodes(Graph, Object)}.
   *
   * <p>Some algorithms that operate on a {@code SuccessorsFunction} may produce undesired results
   * if the returned {@link Iterable} contains duplicate elements. Implementations of such
   * algorithms should document their behavior in the presence of duplicates.
   *