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java.lang.everything
everything.start

start here

what java even is, a JDK on your machine, and your first program running.

start part 01
  1. 01what java actually isthe language, the JDK, the JVM, and why they're three different things.
  2. 02getting a JDKwhich JDK to install (there are like ten), JAVA_HOME, and an editor.
  3. 03hello, worldfrom void main() to public static void main(String[] args), and why both exist.
  4. 04compile and runjavac → .class → java. what each step actually produces.
  5. 05jshella REPL for java. the fastest way to try anything on this site.
  6. 06debugging and stack tracesbreakpoints, stepping, and reading a stack trace without panicking.