You can define logic (code) that should be executed before the application **starts up**. This means that this code will be executed **once**, **before** the application **starts receiving requests**.

The same way, you can define logic (code) that should be executed when the application is **shutting down**. In this case, this code will be executed **once**, **after** having handled possibly **many requests**.

### Installing xl-meta

To install, [Go](https://golang.org/dl/) must be installed. Once installed, execute this to install the binary:

```bash
go install github.com/minio/minio/docs/debugging/xl-meta@latest
```

### Using xl-meta

import java.util.logging.Logger;

import org.apache.commons.io.output.DeferredFileOutputStream;

/**
 * ContentOutputStream is a custom output stream that extends DeferredFileOutputStream.
 * It writes data to a temporary file once the data size exceeds a specified threshold.
 *
 * <p>This class ensures that the temporary file is deleted if it is not needed.
 * It uses a logger to log warnings if there are issues deleting the temporary file.</p>
 *

 *       have, of returning a new, independent iterator
 * </ul>
 *
 * <p>Because of this situation, any public method accepting an iterable should invoke the {@code
 * iterator} method only once, and should be tested using this class. Exceptions to this rule should
 * be clearly documented.
 *
 * <p>Note that although your APIs should be liberal in what they accept, your methods which

/// tip

You normally have to do this only **once**, when you create the virtual environment.

///

## Deactivate the Virtual Environment { #deactivate-the-virtual-environment }

Once you are done working on your project you can **deactivate** the virtual environment.

<div class="termy">

```console
$ deactivate
```

You can use the property `.openapi_schema` as a "cache", to store your generated schema.

That way, your application won't have to generate the schema every time a user opens your API docs.

It will be generated only once, and then the same cached schema will be used for the next requests.

{* ../../docs_src/extending_openapi/tutorial001.py hl[13:14,25:26] *}

### Override the method { #override-the-method }

	return syscall.Exec(argv0, os.Args, os.Environ())
}

// freezeServices will freeze all incoming S3 API calls.
// For each call, unfreezeServices must be called once.
func freezeServices() {
	// Use atomics for globalServiceFreeze, so we can read without locking.
	// We need a lock since we are need the 2 atomic values to remain in sync.
	globalServiceFreezeMu.Lock()

  /*
   * TODO(b/242884182): Figure out why this helps produce the same class file when we compile most
   * of common.collect a second time with the results of the first compilation on the classpath. Or
   * just back this out once we stop doing that (which we'll do after our internal GWT setup
   * changes).
   */
  @Override
  public ImmutableMap<Object, Collection<Object>> asMap() {
    return super.asMap();
  }

 * This class encapsulates HTTP request parameters that can have multiple values,
 * such as query parameters, form parameters, or other request-related data.
 *
 * <p>This class is immutable and thread-safe. Once created, the parameter name
 * and values cannot be modified.</p>
 *
 */
public class RequestParameter {

    /** The name of the request parameter. */
    private final String name;

   */
  fun cancel()

  fun interface Factory {
    /**
     * Creates a new event source and immediately returns it. Creating an event source initiates an
     * asynchronous process to connect the socket. Once that succeeds or fails, `listener` will be
     * notified. The caller must cancel the returned event source when it is no longer in use.
     */
    fun newEventSource(
      request: Request,