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java.lang.everything
everything.generics

generics

type parameters, wildcards, erasure. how java gets type safety without changing the JVM.

start part 05
  1. 01why generics existlife before generics was ClassCastException at 3am.
  2. 02generic types and methodswriting your own Box<T>, and how inference figures out T.
  3. 03bounded type parameters<T extends Comparable<? super T>> decoded.
  4. 04wildcards and PECS? extends vs ? super. producer extends, consumer super.
  5. 05type erasurewhat the compiler deletes, what it adds (bridge methods), and why.
  6. 06arrays, varargs and other limitsno new T(), no generic arrays, heap pollution and @SafeVarargs.
  7. 07generics at runtimetype tokens and the bits of type info that do survive erasure.