# yii2\extensions\psrbridge\exception

> 2 classes, 1 enum of the yii2\extensions\psrbridge\exception namespace.

[API reference](/docs/api/index.md) › [PSR bridge](/docs/extensions/psr-bridge/reference/index.md) › exception

## Classes

| Class | Summary |
| --- | --- |
| [`HeadersAlreadySentException`](/docs/extensions/psr-bridge/reference/exception/headersalreadysentexception/index.md) final | Thrown when code attempts to emit headers after headers are already sent. |
| [`OutputAlreadySentException`](/docs/extensions/psr-bridge/reference/exception/outputalreadysentexception/index.md) final | Thrown when code attempts to emit a response after output is already sent. |

## Enums

| Enum | Summary |
| --- | --- |
| [`Message`](/docs/extensions/psr-bridge/reference/exception/message/index.md) | Defines bridge exception message templates. |