}

    @Nonnull
    @Override
    public Optional<Path> getPath(Project project) {
        Optional<ProducedArtifact> mainArtifact = project.getMainArtifact();
        if (mainArtifact.isPresent()) {
            return artifactManager.getPath(mainArtifact.get());
        }
        return Optional.empty();
    }

    @Nonnull
    @Override

# limitations under the License.
# ==============================================================================

# Usage: Go to
# https://github.com/tensorflow/tensorflow/actions/workflows/release-branch-cherrypick.yml
# and click "Run Workflow." Leave "Use Workflow From" set to "master", then
# input the branch name and paste the cherry-pick commit and click Run. A PR
# will be created.

#ifndef TENSORFLOW_C_EAGER_IMMEDIATE_EXECUTION_OPERATION_H_
#define TENSORFLOW_C_EAGER_IMMEDIATE_EXECUTION_OPERATION_H_

#include <memory>

#include "absl/types/optional.h"
#include "absl/types/span.h"
#include "tensorflow/c/eager/abstract_operation.h"
#include "tensorflow/c/eager/immediate_execution_tensor_handle.h"
#include "tensorflow/c/tensor_interface.h"

            </Export-Package>
            <Import-Package>
              com.google.common.util.concurrent.internal,
              javax.annotation;resolution:=optional,
              javax.crypto.*;resolution:=optional,
              sun.misc.*;resolution:=optional
            </Import-Package>
            <Bundle-DocURL>https://github.com/google/guava/</Bundle-DocURL>
          </instructions>
        </configuration>

本例中，查询参数 `q` 是可选的，默认值为 `None`。

/// check | "检查"

注意，**FastAPI** 可以识别出 `item_id` 是路径参数，`q` 不是路径参数，而是查询参数。

///

/// note | "笔记"

因为默认值为 `= None`，FastAPI 把 `q` 识别为可选参数。

FastAPI 不使用 `Optional[str]` 中的 `Optional`（只使用 `str`），但 `Optional[str]` 可以帮助编辑器发现代码中的错误。

///

## 查询参数类型转换

参数还可以声明为 `bool` 类型，FastAPI 会自动转换参数类型：


//// tab | Python 3.10+

```Python hl_lines="7"

    assertFalse(out.closed());
  }

  public void testClosesOnErrors_copyingToByteSinkThatThrows() {
    for (TestOption option : EnumSet.of(OPEN_THROWS, WRITE_THROWS, CLOSE_THROWS)) {
      TestByteSource okSource = new TestByteSource(bytes);
      assertThrows(IOException.class, () -> okSource.copyTo(new TestByteSink(option)));
      // ensure stream was closed IF it was opened (depends on implementation whether or not it's

policies[0].name=mypolicy,policies[0].statements[0].resources[0]='arn:aws:s3:::bucket1',policies[0].statements[0].actions[0]='s3:ListBucket',policies[0].statements[0].actions[1]='s3:GetObject' minio/minio ``` Description of the configuration parameters used above - - `policies[].name` - name of the policy to create, must be a string with length > 0 - `policies[].statements[]` - list of statements, includes actions and resources - `policies[].statements[].resources[]` - list of resources that applies the statement...

   *     in this instance of the Java virtual machine
   */
  public Optional<Charset> charset() {
    // racy single-check idiom, this is safe because Optional is immutable.
    Optional<Charset> local = parsedCharset;
    if (local == null) {
      String value = null;
      local = Optional.absent();
      for (String currentValue : parameters.get(CHARSET_ATTRIBUTE)) {
        if (value == null) {

        return Objects.equals(p, packaging);
    }

    private static Optional<String> getActivationPackaging(org.apache.maven.model.Profile profile) {
        return Optional.ofNullable(profile)
                .map(org.apache.maven.model.Profile::getDelegate)
                .map(Profile::getActivation)
                .map(Activation::getPackaging);

     *
     * @return the current project or {@code empty()} if not applicable
     */
    @Nonnull
    Optional<Project> getProject();

    /**
     * Gets the current mojo execution (if any).
     *
     * @return the current mojo execution or {@code empty()} if not applicable
     */
    @Nonnull
    Optional<MojoExecution> getMojoExecution();

    /**
     * Gets the exception that caused the event (if any).
     *