NPEs in Java usually have 2 causes and they are easily preventable:

1. Parsing or deserializing data that must be present but is not. Fix: Add a validator or (introduced in Java 17 - 4 years ago) use records and do simple null validation there
2. Devs coding weird shit that might or might not return null. Fix: Use annotations like NotNull/Nullable or the Optional wrapper (introduced in Java 8 - 11 years ago). There is also progress underway to be able to explicity declare type nullness, however - as always - Oracle invests more money into it’s lawyers instead of their devs, so it will take some time until this will be available.

The problem is not really language specific because quite the same can also happen in any programming language, the symptoms/errors are just different.

I like the “advantage” that using any Kotlin code in normal Java automatically forces you to use the kotlin-stdlib for Java 8 and adds a additional bloat of 10MB to your project…

But they were, all of them, deceived

For another format was made.