!592 // auto-import
!1000265 // standard function adder

public class main {
  static String prelude =
    "public class main {\n" +
    "  public static void main(String[] args) throws Exception {\n" +
    "    String s = loadMainJava();\n";
  static String postlude = "\n" +
    "    saveMainJava(s);\n" +
    "  }\n" +
    "}\n";

  public static void main(String[] args) throws IOException {
    String code = loadTextFile("input/main.java", null);
    if (code == null)
      throw new RuntimeException("Nothing to do (no input/main.java)");
    saveTextFile("output/main.java", prelude + code + postlude);
  }
}

Began life as a copy of #609