I am trying to draw class diagrams for my classes.
I have one interface called IFetchContentSource. It has the following details
getContentByLocation(Arraylist location, String source_object_type, ArrayList source_metadata_fields, ArrayList staging_metadata_fields): ContentAndMetadata 
getNumberofDocsByQuery(String from, String where, String object_type): int
The return type of one of the methods of this Interface is ContentAndMetadata, which is defined as
HashMap metadata_fields_values: String staging_metadata_fields, String source_metadata_values
Please let me know how the relation between these two classes be specified using class diagrams. Will there be just an arrow from IFetchContentSource to ContentAndMetadata