Java 8 Stream String Null Or Empty Filter -

i've got google guava inside stream:

this.map.entryset().stream() .filter(entity -> !strings.isnullorempty(entity.getvalue())) .map(obj -> string.format("%s=%s", obj.getkey(), obj.getvalue())) .collect(collectors.joining(",")) 

as see there statement !string.isnullorempty(entity) inside filter function.

i don't want use guava anymore in project, want replace by:

string == null || string.length() == 0; 

how can more elegant?

you can write own predicate:

final predicate<map.entry<?, string>> valuenotnullorempty     = e -> e.getvalue() != null && !e.getvalue().isempty(); 

then use valuenotnullorempty filter argument.