java - How to write an ImmutableMap that follows the Liskov Subsitution and other SOLID principles without code smells? -

i answered question regaurding immutablemap. suggested using proxy pattern.

the problem map contains put method, throw unsupportedoperationexception. replacing other instances of map immutablemap break liskov subsitution principle. not that, need declare put , putall [violates interface segregation principle]

technically, there no way replace map instance immutablemap, since map interface. question is:

would creating immutablemap using map interface considered breaking lsp, since map contains put , putall method? not implementing map considered "alternative classes different interfaces" code smell? how 1 create immutablemap abides lsp yet doesn't contain code smells?

in view, immutablemap should implement map. bad idea not implement map there many methods accept map argument , use in read-only sense. don't believe violate liskov subsitution principle because contract map makes clear put optional operation.

it not ideal classes implementing map have implement put, alternative have been have complex hierarchy of interfaces each including subset of possible optional methods. if there n optional methods, there have 2^n interfaces cover combinations. don't know value of n, there non-obvious optional operations, such whether or not iterator returned map.entryset().iterator() supports setvalue operation. if combined hierarchy hierarchy of interfaces , abstract classes exists (including abstractmap, sortedmap, navigablemap, concurrentmap, concurrentnavigablemap...) have total mess.

so there no perfect answer this, in view best solution make immutablemap implement map , ensure every method write map argument documents properties map must have , exceptions thrown if wrong type of map passed.