return get(key).add(value);
  }

  @CanIgnoreReturnValue
  @Override
  public boolean putAll(@ParametricNullness K key, Iterable<? extends V> values) {
    checkNotNull(values);
    // make sure we only call values.iterator() once
    // and we only call get(key) if values is nonempty
    if (values instanceof Collection) {
      Collection<? extends V> valueCollection = (Collection<? extends V>) values;

- **Network Layer**: Transport abstraction, NetBIOS name resolution, session management

### Contributing

We welcome contributions! Please:
1. Fork the repository
2. Create a feature branch
3. Make your changes with appropriate tests
4. Run `mvn clean test` to ensure all tests pass
5. Submit a pull request

### License

        ByteArrayOutputStream baos = new ByteArrayOutputStream();
        writeLittleEndianInt(baos, 0); // buffer count = 0
        writeLittleEndianInt(baos, 99); // invalid version
        baos.write(new byte[1]); // Make it > 8 bytes
        byte[] pacData = baos.toByteArray();

        PACDecodingException e = assertThrows(PACDecodingException.class, () -> new Pac(pacData, keys));
        // The error could be about version or missing buffers

        verifyNoInteractions(mockDir);
    }

    /**
     * Interaction with dependency: implementation can use directory's methods to make decisions.
     * Tests a filter that uses directory path information.
     */
    @Test
    @DisplayName("filter can use SmbFile directory for decision logic")
    void filterCanUseSmbFileForDecision() throws Exception {

---

## Install FastAPI { #install-fastapi }

The first step is to install FastAPI.

Make sure you create a [virtual environment](../virtual-environments.md){.internal-link target=_blank}, activate it, and then **install FastAPI**:

<div class="termy">

```console
$ pip install "fastapi[standard]"

# TF does not support python3.13.
RUN ln -sf /usr/bin/python3.12 /usr/bin/python3
RUN ln -sf /usr/bin/python3.12 /usr/bin/python
RUN ln -sf /usr/lib/python3.12 /usr/lib/tf_python

# Make sure clang is on the path
RUN ln -s /usr/lib/llvm-18/bin/clang /usr/bin/clang

# Link the compat driver to the location if available.

       * doesn't need access to the futures again, so we can just pass `null`.
       *
       * TODO(b/112550045): Allocating a single, cheaper listener is (I think) only an optimization.
       * If we make some other optimizations, this one will no longer be necessary. The optimization
       * could actually hurt in some cases, as it forces us to keep all inputs in memory until the
       * final input completes.
       */

## Dispatch

For synchronous calls, you bring your own thread and are responsible for managing how many simultaneous requests you make. Too many simultaneous connections wastes resources; too few harms latency.

      return x.longValue();
    } else if (exponent > MAX_EXPONENT) {
      return x.signum() * POSITIVE_INFINITY;
    }

    /*
     * We need the top SIGNIFICAND_BITS + 1 bits, including the "implicit" one bit. To make rounding
     * easier, we pick out the top SIGNIFICAND_BITS + 2 bits, so we have one to help us round up or
     * down. twiceSignifFloor will contain the top SIGNIFICAND_BITS + 2 bits, and signifFloor the

<img src="/img/tutorial/dataclasses/image01.png">

## Dataclasses in Nested Data Structures { #dataclasses-in-nested-data-structures }

You can also combine `dataclasses` with other type annotations to make nested data structures.

In some cases, you might still have to use Pydantic's version of `dataclasses`. For example, if you have errors with the automatically generated API documentation.