E então você também leu como lidar com [CORS com o `CORSMiddleware`](../tutorial/cors.md).

Nesta seção, veremos como usar outros middlewares.

## Adicionando middlewares ASGI { #adding-asgi-middlewares }

import org.jspecify.annotations.Nullable;

/**
 * A {@code SetMultimap} whose set of values for a given key are kept sorted; that is, they comprise
 * a {@link SortedSet}. It cannot hold duplicate key-value pairs; adding a key-value pair that's
 * already in the multimap has no effect. This interface does not specify the ordering of the
 * multimap's keys. See the {@link Multimap} documentation for information common to all multimaps.
 *

import java.util.Collection;
import java.util.Map;
import java.util.Map.Entry;
import java.util.Set;
import org.jspecify.annotations.Nullable;

/**
 * A {@code Multimap} that cannot hold duplicate key-value pairs. Adding a key-value pair that's
 * already in the multimap has no effect. See the {@link Multimap} documentation for information
 * common to all multimaps.
 *

import java.util.Collection;
import java.util.Map;
import java.util.Map.Entry;
import java.util.Set;
import org.jspecify.annotations.Nullable;

/**
 * A {@code Multimap} that cannot hold duplicate key-value pairs. Adding a key-value pair that's
 * already in the multimap has no effect. See the {@link Multimap} documentation for information
 * common to all multimaps.
 *

    }
    assertWithMessage("table size after adding %s elements", size)
        .that(bucketsOf(map1))
        .isEqualTo(initialBuckets);

    /*
     * Something slightly different happens when the entries are added all at
     * once; make sure that passes too.
     */
    map2.putAll(map1);
    assertWithMessage("table size after adding %s elements", size)
        .that(bucketsOf(map1))

If you did not have a Adoptium Java 17 SDK installed before importing the project into IntelliJ and after adding Adoptium Java 17 SDK your IntelliJ still uses the wrong SDK version, you might need to invalidate IntelliJ's caches before reloading the project.

#### Install Develocity IntelliJ plugin

* Path `prefix`: `/items`.
* `tags`: (just one tag: `items`).
* Extra `responses`.
* `dependencies`: they all need that `X-Token` dependency we created.

So, instead of adding all that to each *path operation*, we can add it to the `APIRouter`.

{* ../../docs_src/bigger_applications/app_an_py310/routers/items.py hl[5:10,16,21] title["app/routers/items.py"] *}

    putEdge(1, 2); // Duplicate
    putEdge(4, 5);
  }

  // Element Mutation

  @Test
  public void putEdge_existingNodes() {
    assume().that(graphIsMutable()).isTrue();

    // Adding nodes initially for safety (insulating from possible future
    // modifications to proxy methods)
    addNode(N1);
    addNode(N2);

    assertThat(graphAsMutableGraph.putEdge(N1, N2)).isTrue();
  }

}

func TestLRUEdgeCases(t *testing.T) {
	lc := lru.NewLRU[string, *string](2, nil, 0)

	// Adding a nil value
	lc.Add("key1", nil)

	value, exists := lc.Get("key1")
	if value != nil || !exists {
		t.Fatalf("unexpected value or existence flag for key1: value=%v, exists=%v", value, exists)
	}

	// Adding an entry with the same key but different value
	newVal := "val1"
	lc.Add("key1", &newVal)

<div class="termy">

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

---> 100%
```

</div>

A similar process would apply to any other ASGI server program.

/// tip

By adding the `standard`, Uvicorn will install and use some recommended extra dependencies.

That including `uvloop`, the high-performance drop-in replacement for `asyncio`, that provides the big concurrency performance boost.