void resetSingleton() {
        try {
            Field instance = SingletonContext.class.getDeclaredField("INSTANCE");
            instance.setAccessible(true);
            instance.set(null, null);
        } catch (NoSuchFieldException | IllegalAccessException e) {
            log.error("Failed to reset SingletonContext instance", e);
            fail("Failed to reset SingletonContext instance: " + e.getMessage());
        }

        try {
            Field f = target.getClass().getDeclaredField(name);
            f.setAccessible(true);
            f.set(target, value);
        } catch (Exception e) {
            fail("Failed to set field '" + name + "'", e);
        }
    }

    /**
     * Helper for getting a field via reflection.
     */

        override fun onResponse(
          call: Call,
          response: Response,
        ) {
          val socket =
            try {
              checkUpgradeSuccess(response)
            } catch (e: IOException) {
              failWebSocket(e, response)
              response.closeQuietly()
              response.socket?.sink?.closeQuietly()
              response.socket?.source?.closeQuietly()

          if (nextPlan != null) {
            routePlanner.deferredPlans.addFirst(nextPlan)
            continue
          }
        }
        return plan.handleSuccess()
      } catch (e: IOException) {
        if (firstException == null) {
          firstException = e
        } else {
          firstException.addSuppressed(e)
        }
        if (!routePlanner.hasNext()) {

   */
  @JvmOverloads
  fun charset(defaultValue: Charset? = null): Charset? {
    val charset = parameter("charset") ?: return defaultValue
    return try {
      Charset.forName(charset)
    } catch (_: IllegalArgumentException) {
      defaultValue // This charset is invalid or unsupported. Give up.
    }
  }

  /**
   * Returns the parameter [name] of this media type, or null if this media type does not define

    }

    @Test
    void testActivityTracking() {
        long initialTime = channelInfo.getLastActivityTime();

        // Wait a bit and update activity
        try {
            Thread.sleep(10);
        } catch (InterruptedException e) {
            Thread.currentThread().interrupt();
        }

        channelInfo.updateActivity();
        assertTrue(channelInfo.getLastActivityTime() > initialTime);

        PreauthIntegrityNegotiateContext ctx = new PreauthIntegrityNegotiateContext();
        try {
            setPrivateField(ctx, "hashAlgos", new int[] { PreauthIntegrityNegotiateContext.HASH_ALGO_SHA512 });
        } catch (Exception e) {
            throw new RuntimeException(e);
        }
        return ctx;
    }

    private NegotiateContextRequest createMockEncryptionContext() {

        try {
            return accessTokenService.getPermissions(request)
                    .map(permissions -> fessConfig.isApiAdminAccessAllowed(permissions))
                    .orElse(false);
        } catch (final InvalidAccessTokenException e) {
            if (logger.isDebugEnabled()) {
                logger.debug("Invalid access token.", e);
            }
            return false;
        }
    }

            return 4;
        }

        try {
            securityDescriptor = new SecurityDescriptor();
            bufferIndex += securityDescriptor.decode(buffer, bufferIndex, len);
        } catch (final IOException ioe) {
            throw new RuntimeException(ioe.getMessage());
        }

        return bufferIndex - start;
    }

    @Override
    public String toString() {

            - iter_json
            - send_text
            - send_bytes
            - send_json
            - close

When a client disconnects, a `WebSocketDisconnect` exception is raised, you can catch it.

You can import it directly form `fastapi`:

```python
from fastapi import WebSocketDisconnect
```

::: fastapi.WebSocketDisconnect

## WebSockets - additional classes