public String getDefaultScheme() {
        return this.defaultScheme;
    }
Get the default scheme that should be used, if the client doesn't specify a scheme/address.

@return The default scheme to use or null.
@see #setDefaultScheme(String)
grpc-client-spring-boot-starter/src/main/java/net/devh/boot/grpc/client/config/GrpcChannelsProperties.java