You could use a tool like api-spec-converter from npm to convert swagger to WADL.
Usage:
$ api-spec-converter -h
Usage: api-spec-converter [options] <URL|filename>
Convert API descriptions between popular formats.
Supported formats:
* swagger_1
* swagger_2
* openapi_3
* api_blueprint
* io_docs
* google
* raml
* wadl
Options:
-h, --help output usage information
-V, --version output the version number
-f, --from <format> Specifies format to convert
-t, --to <format> Specifies output format
-s, --syntax [syntax] Specifies output data syntax: json or yaml. Defaults to json
-o, --order [sortOrder] Specifies top fields ordering: openapi or alpha. Defaults to openapi
-c, --check Check if result is valid spec
-d, --dummy Fill missing required fields with dummy data
Then, you could generate the POJO using the wadl2java
CXF maven plugin.