Tile Fuser throws class cast exception if the first defined tile format is not an image type

[smithkm]

To Replicate:

• Create a layer with both vector tiles and PNG images in that order.
• Enable FullWMS/Tile Fusing.
• Make a non-tiled PNG WMS request for that layer.

The following error will be thrown.

400: class org.geowebcache.mime.ApplicationMime cannot be cast to class org.geowebcache.mime.ImageMime (org.geowebcache.mime.ApplicationMime and org.geowebcache.mime.ImageMime are in unnamed module of loader org.apache.catalina.loader.ParallelWebappClassLoader @6134ac4a)

The cast causing the problem occurs at these locations:

• https://github.com/GeoWebCache/geowebcache/blob/1.24.2/geowebcache/wms/src/main/java/org/geowebcache/service/wms/WMSTileFuser.java#L325)
• https://github.com/GeoWebCache/geowebcache/blob/1.24.2/geowebcache/wms/src/main/java/org/geowebcache/service/wms/WMSTileFuser.java#L381

Work arounds:

• Disable vector tiles if you want to have tile fusing
• Change the cache definition so that the first tile format is an image type.