> If I take a book and change the names of all the characters, I will still get sued. Renaming APIs and making a derived work is not in any way certain to prevent lawsuits like this one.

This is not an apt analogy, because this isn't what happened. Google wrote all of the implementations from scratch: the only thing they copied was the character names (and potentially one tiny function used for sorting). This is more akin to taking the Wikipedia summary of the plot of a book and writing a new book based on that summary.

This actually the very analogy used by Oracle lawyer that won the appeal.

As the comment above states, it was based on Apache Harmony not written from scratch.

But Apache Harmony isn't owned by Oracle; for the purpose, it doesn't matter if Google wrote it themselves or got someone else to write it.