Hashmap filtering in java lambda

Question

Want a functional style filtering on two hashmap...

Say... I got a hashmap data as given map from database

    Map<String, Object> user=new HashMap<>();
    user.put("Name", "SomeName");
    user.put("Role", userRoles);
    //some relevant keys and value

The userRoles is a list of strings like below..

    List<String> userRoles = new ArrayList<>();
    userRoles.add("User");
    userRoles.add("Admin");

And the service permission from db

    List<String> servicePermission = new ArrayList<>();
    servicePermission.add("User");
    servicePermission.add("Public");

Now I want to filter with lambda... if any of userRoles exists in servicePermission list return true or return false/exception.

Thanks in advance

Answer 1

You can do the following.

return ((List<String>) user.get("Role")).stream()
                           .anyMatch(servicePermisions::contains);

Answer 2

You can use anyMatch :

boolean match = 
    user.get("Role").stream()
                    .anyMatch(s -> servicePermission.contains(s));