Don't mix LocalDate and Calendar. You are right to use LocalDate, so stop using Calendar. Have you been through the Java™ Tutorials about dates? I am pretty sure you can get a date object for “next Monday” or “last Friday”.
They say local date is immutable and show an example with 14th May. I always thought they used 23rd May, which is Duke's Birthday
Try the section called Date Classes for an example with “next Wednesday”.