=====================

OkHttp 4.x upgrades our implementation language from Java to Kotlin and keeps everything else the
same. We’ve chosen Kotlin because it gives us powerful new capabilities while integrating closely
with Java.

We spent a lot of time and energy on retaining strict compatibility with OkHttp 3.x. We’re even
keeping the package name the same: `okhttp3`!

There are three kinds of compatibility we’re tracking:

import javax.annotation.CheckForNull;

/**
 * Executor ensuring that all Runnables submitted are executed in order, using the provided
 * Executor, and sequentially such that no two will ever be running at the same time.
 *
 * <p>Tasks submitted to {@link #execute(Runnable)} are executed in FIFO order.
 *
 * <p>The execution of tasks is done by one thread as long as there are tasks left in the queue.

          new ExpectedHashCode(
              new byte[] {
                (byte) 0xef, (byte) 0xcd, (byte) 0xab, (byte) 0x89,
                (byte) 0x67, (byte) 0x45, (byte) 0x23,
                    (byte) 0x01, // up to here, same bytes as above
                (byte) 0x01, (byte) 0x02, (byte) 0x03, (byte) 0x04,
                (byte) 0x05, (byte) 0x06, (byte) 0x07, (byte) 0x08
              },
              0x89abcdef,

import javax.annotation.CheckForNull;

/**
 * Executor ensuring that all Runnables submitted are executed in order, using the provided
 * Executor, and sequentially such that no two will ever be running at the same time.
 *
 * <p>Tasks submitted to {@link #execute(Runnable)} are executed in FIFO order.
 *
 * <p>The execution of tasks is done by one thread as long as there are tasks left in the queue.

```

</div>

It will serve the documentation on `http://127.0.0.1:8008`.

That way, you can edit the documentation/source files and see the changes live.

/// tip

Alternatively, you can perform the same steps that scripts does manually.

Go into the language directory, for the main docs in English it's at `docs/en/`:

```console
$ cd docs/en/
```

Then run `mkdocs` in that directory:

```console

   * Calling this method is as thread-safe as calling that method.
   *
   * @param collection a collection of {@code Number} instances
   * @return an array containing the same values as {@code collection}, in the same order, converted
   *     to primitives
   * @throws NullPointerException if {@code collection} or any of its elements is null
   * @since 1.0 (parameter was {@code Collection<Integer>} before 12.0)
   */

Addresses specify a webserver (like `github.com`) and all of the **static** configuration necessary to connect to that server: the port number, HTTPS settings, and preferred network protocols (like HTTP/2).

     * bitset by bitwise ORing the <tt>ATTR_*</tt> constants. Setting the
     * value returned by <tt>getAttributes</tt> will result in both files
     * having the same attributes.
     * 
     * @param attrs
     *            attribute flags
     * 
     * @throws CIFSException
     */
    void setAttributes ( int attrs ) throws CIFSException;


    /**

    [some annotation-only dependencies][guava-deps], which we discuss in more
    detail at that link.

4.  Serialized forms of ALL objects are subject to change unless noted
    otherwise. Do not persist these and assume they can be read by a future
    version of the library.

5.  Our classes are not designed to protect against a malicious caller. You
    should not use them for communication between trusted and untrusted code.

        copyToList(
            getSubjectGenerator()
                .getSampleElements(getSubjectGenerator().getCollectionSize().getNumElements()));
    sort(values, navigableSet.comparator());

    // some tests assume SEVERAL == 3
    if (values.size() >= 1) {
      a = values.get(0);
      if (values.size() >= 3) {
        b = values.get(1);
        c = values.get(2);
      }
    }
  }