String path = request.getUserProperties().getProperty(Constants.MAVEN_USER_CONF);
            if (path == null) {
                path = request.getSystemProperties().getProperty("user.home") + File.separator + ".m2";
            }
            localRepositoryPath = new File(path, "repository").getAbsolutePath();
        }

        try {

import java.util.function.Predicate;
import java.util.stream.Collectors;
import java.util.stream.Stream;

import static java.util.stream.Collectors.toSet;

/**
 * Container for storing the request from the user to activate or deactivate certain projects and optionally fail the
 * build if those projects do not exist.
 */
public class ProjectActivation {
    private static class ProjectActivationSettings {
        /**

// The RuntimeClass is used to determine which container runtime is used to run
// all containers in a pod. RuntimeClasses are (currently) manually defined by a
// user or cluster provisioner, and referenced in the PodSpec. The Kubelet is
// responsible for resolving the RuntimeClassName reference before running the
// pod.  For more details, see

            tempDir.delete();
            tempDir.mkdirs();

            // robots.txt
            StringBuilder buf = new StringBuilder();
            buf.append("User-agent: *").append('\n');
            buf.append("Disallow: /admin/").append('\n');
            buf.append("Disallow: /websvn/").append('\n');
            final File robotTxtFile = new File(tempDir, "robots.txt");

也可以在*响应*生成但是返回之前添加代码.

例如你可以添加自定义请求头 `X-Process-Time` 包含以秒为单位的接收请求和生成响应的时间:

```Python hl_lines="10  12-13"
{!../../docs_src/middleware/tutorial001.py!}
```

## 其他中间件

你可以稍后在 [Advanced User Guide: Advanced Middleware](../advanced/middleware.md){.internal-link target=_blank}阅读更多关于中间件的教程.

    }
  }

  /**
   * Returns an optional enum constant for the given type, using {@link Enum#valueOf}. If the
   * constant does not exist, {@link Optional#absent} is returned. A common use case is for parsing
   * user input or falling back to a default enum constant. For example, {@code
   * Enums.getIfPresent(Country.class, countryInput).or(Country.DEFAULT);}
   *
   * @since 12.0
   */

// Represents either a MlirTensor or a GraphTensor.
// This base class does not expose any public methods other than to distinguish
// which subclass it actually is. The user is responsible to use the right
// type of AbstractTensor in their context (do not pass an MlirTensor to a
// GraphContext and vice-versa).
class TracingTensorHandle : public AbstractTensorHandle {
 protected:

 * </a></li>
 * </ul>
 *
 * @author bowez
 * @author shinsuke
 *
 */
public class RobotsTxtHelper {

    protected static final Pattern USER_AGENT_RECORD =
            Pattern.compile("^user-agent:\\s*([^\\t\\n\\x0B\\f\\r]+)\\s*$", Pattern.CASE_INSENSITIVE);

    protected static final Pattern DISALLOW_RECORD = Pattern.compile("^disallow:\\s*([^\\s]*)\\s*$", Pattern.CASE_INSENSITIVE);

                        final String userCode = userInfoHelper.getUserCode();

                        if (StringUtil.isBlank(userCode)) {
                            throw new WebApiException(HttpServletResponse.SC_BAD_REQUEST, "No user session.");
                        }
                        if (StringUtil.isBlank(favoriteUrl)) {
                            throw new WebApiException(HttpServletResponse.SC_BAD_REQUEST, "URL is null.");

			// For any config error, we don't need to drop into safe-mode
			// instead its a user error and should be fixed by user.
			if errors.As(err, &cerr) {
				logger.FatalIf(err, "Unable to initialize the server")
			}

			// If context was canceled
			if errors.Is(err, context.Canceled) {
				logger.FatalIf(err, "Server startup canceled upon user request")
			}

			bootLogIf(GlobalContext, err)
		}