The beauty and power of Java lies in its strong type system … For the most part, types are helpful, until we start erasing them to get away with a sorry-not-sorry workaround that’s not so easy on the eyes but flies under the radar at compile time, sometimes even at runtime.

In my series of hacking on the Java compiler, we will focus this session on adding new compiler warnings for not so elegant code patterns.

Steps

• Task 0 : setup environment and IDE
• Task 1 : compile the compiler and link it
• Task 2 : lint everything (mirror the -Xlint:all behaviour)
• Task 3 : introduce a new lint bad-cast option

Written documentation will be provided

Necessary Tools

• GitHub account
• Java 19
• Maven for testing the freshly built compiler on an existing project
• Docker (which would provide the required Java and Maven environment dependencies)

Takeaways

• Get some exposure to OpenJDK development loop
• Learn to navigate around OpenJDK project