They tend to require more complex configurations, a message/job queue manager, like RabbitMQ or Redis, but they allow you to run background tasks in multiple processes, and especially, in multiple servers.

But if you need to access variables and objects from the same **FastAPI** app, or you need to perform small background tasks (like sending an email notification), you can simply just use `BackgroundTasks`.

        new SecureRandom().nextBytes(secondFileId);

        // When - set file ID multiple times
        assertDoesNotThrow(() -> {
            request.setFileId(firstFileId);
            request.setFileId(secondFileId);
            request.setFileId(testFileId);
        }, "Should handle multiple setFileId calls");
    }

    @Test
    @DisplayName("Should test interface with anonymous implementation")

The client (browser) will know that the response comes from the correct server because it is using the cryptography they agreed using the **HTTPS certificate** before.

### Multiple Applications { #multiple-applications }

In the same server (or servers), there could be **multiple applications**, for example, other API programs or a database.

	I        MultiFlag
	PrintOut int
	DebugV   bool
)

func init() {
	flag.Var(&D, "D", "predefined symbol with optional simple value -D=identifier=value; can be set multiple times")
	flag.Var(&I, "I", "include directory; can be set multiple times")
	flag.BoolVar(&DebugV, "v", false, "print debug output")
	flag.Var(objabi.NewDebugFlag(&DebugFlags, nil), "d", "enable debugging settings; try -d help")
	objabi.AddVersionFlag() // -V

        assertEquals("NTLM", request.getAuthType());
        verify(mockPrincipal, times(1)).getName();
    }

    @ParameterizedTest
    @ValueSource(strings = { "", "   ", "unknown" })
    @DisplayName("supports multiple principal name variants")
    void testPrincipalNameVariants(String name, @Mock HttpServletRequest mockRequest, @Mock Principal mockPrincipal) {
        when(mockPrincipal.getName()).thenReturn(name);

import java.util.Set;

/**
 * Filter to only retain objects in the given scope or better. This implementation allows the accumulation of multiple
 * scopes and their associated implied scopes, so that the user can filter apply a series of implication rules in a
 * single step. This should be a more efficient implementation of multiple standard {@link ScopeArtifactFilter}
 * instances ORed together.
 *
 */

### Phase 3: Multi-Channel Support
**Priority: MEDIUM** | **Estimated Effort: 5-6 weeks**

Multi-channel enables using multiple network connections for improved performance and reliability.

#### 3.1 Core Multi-Channel Infrastructure
```
Package: jcifs.internal.smb2.multichannel
├── ChannelManager.java           - Manage multiple channels per session
├── ChannelBinding.java           - Channel binding and security

<div class="screenshot">
<img src="/img/tutorial/sql-databases/image01.png">
</div>

## Update the App with Multiple Models { #update-the-app-with-multiple-models }

Now let's **refactor** this app a bit to increase **security** and **versatility**.

		},
		{ // Filter without And and multiple Tag tags
			inputXML: ` <Filter>
							<Prefix>key-prefix</Prefix>
							<Tag>
								<Key>key1</Key>
								<Value>value1</Value>
							</Tag>
							<Tag>
								<Key>key2</Key>
								<Value>value2</Value>
							</Tag>
						</Filter>`,
			expectedErr: errInvalidFilter,
		},
		{ // Filter with And, Prefix & multiple Tag tags
			inputXML: ` <Filter>

            assertEquals(0, init.getContextFlags());
        }

        @Test
        @DisplayName("Multiple flags can be combined correctly")
        void testMultipleFlagsCombination() {
            NegTokenInit init = new NegTokenInit();

            // Set multiple flags
            init.setContextFlag(NegTokenInit.DELEGATION, true);
            init.setContextFlag(NegTokenInit.INTEGRITY, true);