## Gerenciadores de contexto

### O que são gerenciadores de contexto

"Gerenciadores de Contexto" são qualquer um dos objetos Python que podem ser utilizados com a declaração `with`.

        @Test
        @DisplayName("Should handle null context in array")
        void testNullContextInArray() {
            CreateContextRequest[] contexts = new CreateContextRequest[4];
            contexts[0] = new MockCreateContextRequest("FIRST");
            contexts[1] = null; // Null context
            contexts[2] = new MockCreateContextRequest("THIRD");
            contexts[3] = new MockCreateContextRequest("FOURTH");

            contexts[2] = new TestCreateContextResponse("CONTEXT3".getBytes(StandardCharsets.UTF_8));

            // Decode each context
            for (int i = 0; i < contexts.length; i++) {
                contexts[i].decode(buffer, i * 100, 50);
            }

            // Verify each context
            for (int i = 0; i < contexts.length; i++) {
                assertNotNull(contexts[i].getName());

        DirectoryLeaseContext context = new DirectoryLeaseContext(key, leaseState, scope);

        assertEquals(key, context.getLeaseKey());
        assertEquals(leaseState, context.getLeaseState());
        assertEquals(scope, context.getCacheScope());
        assertEquals(30000L, context.getMaxCacheAge());
        assertTrue(context.isNotificationEnabled());
        assertEquals(0, context.getNotificationFilter());
    }

        // At offset 128 + 64 (header start), set context with excessive data length
        int contextPos = 192;
        SMBUtil.writeInt2(1, buffer, contextPos); // Context type
        SMBUtil.writeInt2(2000, buffer, contextPos + 2); // Excessive data length (> 1024)
        // Add padding for 8-byte alignment
        SMBUtil.writeInt2(0, buffer, contextPos + 4); // Reserved

                testEncryptionKey, testDecryptionKey);

        // When/Then - Multiple closes should be safe
        assertDoesNotThrow(() -> {
            context.close();
            context.close();
            context.close();
        });

        assertTrue(context.isClosed());
    }

        // Then
        NegotiateContextRequest[] contexts = request.getNegotiateContexts();
        assertNotNull(contexts);
        assertEquals(2, contexts.length);

        // Verify preauth context
        assertTrue(contexts[0] instanceof PreauthIntegrityNegotiateContext);
        assertEquals(PreauthIntegrityNegotiateContext.NEGO_CTX_PREAUTH_TYPE, contexts[0].getContextType());

        // Verify encryption context

* dependable: dependable (do not translate to "confiable" or "fiable")
* list (as in Python list): list
* context manager: context manager (do not translate to "gestor de contexto" or "administrador de contexto")
* a little bit: un poquito
* graph (data structure, as in "dependency graph"): grafo (do not translate to "gráfico")

            throw new CIFSException("Preauth integrity context is invalid for session: " + sessionId);
        }

        try {
            byte[] newHash = calculateHash(context.getCurrentHash(), messageData, context.getHashAlgorithm());
            context.updateHash(newHash);

            log.debug("Updated preauth hash for session {} with {} bytes of data", sessionId, messageData.length);

* `close()`: Fecha o arquivo.

Como todos esses métodos são assíncronos (`async`) você precisa esperar ("await") por eles.

Por exemplo, dentro de uma *função de operação de rota* assíncrona você pode obter os conteúdos com:

```Python
contents = await myfile.read()
```