Migrate users of Optional.get()
Optional.orElseThrow() has a more explicit name, preventing potential
confusion with Future.get() and making it clear there might be an
exception coming.
Also take the time to modernize code with local variable type inference,
instanceof patterns and similar.
Change-Id: Ifca580e0f6c652da270260dc126f79d7f32b9ff2
Signed-off-by: Robert Varga <robert.varga@pantheon.tech>
(cherry picked from commit
c5e2515ee057d1a7f63d88053a77678739356054)
(cherry picked from commit
b66cbba275126b82d2951bbd812c05fb3f21a74d)