Proc-macro implementation for inline_java.

Provides three proc macros for embedding Java in Rust:

All macros require the user to write a static <T> run(...) method where T is one of: byte, short, int, long, float, double, boolean, char, String, T[], List<T>, or Optional<T> — including arbitrarily nested types like List<List<Integer>>, Optional<List<String>>, Optional<List<Optional<Integer[]>>>, etc.

Wire format (Java → Rust, stdout)

The macro generates a main() that binary-serialises run()'s return value to stdout via DataOutputStream (raw UTF-8 for top-level String scalars).

Encoding per type:

• Boxed(String) at top level: raw UTF-8 (no length prefix)
• Boxed(String) inside a container: 4-byte BE length + UTF-8 bytes
• Primitive / Boxed(non-String): fixed-width big-endian bytes via DataOutputStream
• Array(T) / List(T): 4-byte BE count + N × encode(T)
• Optional(T): 1-byte tag (0=absent, 1=present) + encode(T) if present

Wire format (Rust → Java, stdin)

Parameters declared in run(...) are serialised by Rust and piped to the child process's stdin. Java reads them with DataInputStream.

Options

All three macros accept zero or more key = "value" pairs before the Java body, comma-separated. Recognised keys:

• javac = "<args>" — extra arguments passed verbatim to javac (shell-quoted; single/double quotes respected).
• java = "<args>" — extra arguments passed verbatim to java (shell-quoted; single/double quotes respected).

inline_java_macros

Support crate for inline_java — not intended for direct use.

Please refer to the main crate for documentation and usage examples.