$ java broken/NoMain.java     (JDK 25)
broken/NoMain.java:1: error: compact source file does not have main method in the form of void main() or void main(String[] args)
void greet() { IO.println("hi"); }
^
1 error
error: compilation failed

$ java broken/NoIoPrefix.java     (JDK 25)
broken/NoIoPrefix.java:2: error: cannot find symbol
    println("hello");
    ^
  symbol:   method println(String)
  location: class NoIoPrefix
1 error
error: compilation failed

$ java broken/NotInJavaBase.java     (JDK 25)
broken/NotInJavaBase.java:2: error: cannot find symbol
    HttpClient client = HttpClient.newHttpClient();
    ^
  symbol:   class HttpClient
  location: class NotInJavaBase
broken/NotInJavaBase.java:2: error: cannot find symbol
    HttpClient client = HttpClient.newHttpClient();
                        ^
  symbol:   variable HttpClient
  location: class NotInJavaBase
2 errors
error: compilation failed

$ java broken/WithPackage.java     (JDK 25)
broken/WithPackage.java:1: error: compact source file should not have package declaration
package demo;
^
1 error
error: compilation failed

$ javac -d out broken/Other.java broken/Target.java     (JDK 25; Target.java is a compact file)
broken/Other.java:2: error: Target is abstract; cannot be instantiated
    Target t = new Target();
               ^
broken/Other.java:3: error: cannot find symbol
    t.main();
     ^
  symbol:   method main()
  location: variable t of type Target
2 errors

$ java broken/Other.java     (JDK 25; source launcher, Target.java sits next to it)
broken/Other.java:2: error: Target is abstract; cannot be instantiated
    Target t = new Target();
               ^
1 error
error: compilation failed

$ java broken/WrongParam.java     (JDK 25)
broken/WrongParam.java:1: error: compact source file does not have main method in the form of void main() or void main(String[] args)
void main(int count) { IO.println("count = " + count); }
^
1 error
error: compilation failed

$ java broken/PrivateMain.java     (JDK 25)
error: can't find main(String[]) or main() method in class: PrivateMain

$ java broken/CtorWithArgs.java     (JDK 25)
error: can't find no argument constructor in class: CtorWithArgs