@GET
    @Path("protocols")
    public Map<String, ProtocolInfo> getProtocols() throws GuacamoleException {

        // Get and return a map of all protocols.
        Environment env = LocalEnvironment.getInstance();
        return env.getProtocols();

    }
Gets a map of protocols defined in the system - protocol name to protocol.

@return
    A map of protocol information, where each key is the unique name
    associated with that protocol.

@throws GuacamoleException
    If an error occurs while retrieving the available protocols.
guacamole/src/main/java/org/apache/guacamole/rest/schema/SchemaResource.java