docs: private String loadSource(String sourceUrl) {
          String source = null;
          int hash = sourceUrl.indexOf('#');
          if (hash >= 0) {
              sourceUrl = sourceUrl.substring(0, hash);
          }
          try {
              InputStream is;
            openStream:
              {
                  if (sourceUrl.indexOf(':') < 0) {
                      // Can be a file name
                      try {
                          if (sourceUrl.startsWith("~/")) {
                              String home = SecurityUtilities.getSystemProperty("user.home");
                              if (home != null) {
                                  String pathFromHome = sourceUrl.substring(2);
                                  File f = new File(new File(home), pathFromHome);
                                  if (f.exists()) {
                                      is = new FileInputStream(f);
                                      break openStream;
                                  }
                              }
                          }
                          File f = new File(sourceUrl);
                          if (f.exists()) {
                              is = new FileInputStream(f);
                              break openStream;
                          }
                      } catch (SecurityException ex) { }
                      // No existing file, assume missed http://
                      if (sourceUrl.startsWith("//")) {
                          sourceUrl = "http:" + sourceUrl;
                      } else if (sourceUrl.startsWith("/")) {
                          sourceUrl = "http://127.0.0.1" + sourceUrl;
                      } else {
                          sourceUrl = "http://" + sourceUrl;
                      }
                  }
  
                  is = (new URL(sourceUrl)).openStream();
              }
  
              try {
                  source = Kit.readReader(new InputStreamReader(is));
              } finally {
                  is.close();
              }
          } catch (IOException ex) {
              System.err.println
                  ("Failed to load source from "+sourceUrl+": "+ ex);
          }
          return source;
      }