According to WMS 1.1.1 and 1.3.0 standard definition, the request url for WMS requests may be done without specifying a specific layer selection. In such a case, all server-layers will be rendered into the requested image.
In such a case, the request url may not contain the "&LAYERS=" because that is not allowed to be empty.
I think adding an isEmpty (or equals "") check in WmsLayerOptions.java and then not setting the layers option should already fix this issue.
According to WMS 1.1.1 and 1.3.0 standard definition, the request url for WMS requests may be done without specifying a specific layer selection. In such a case, all server-layers will be rendered into the requested image.
In such a case, the request url may not contain the "&LAYERS=" because that is not allowed to be empty.
I think adding an isEmpty (or equals "") check in WmsLayerOptions.java and then not setting the layers option should already fix this issue.