thow_vs_return_issue.java

  @Override
  public synchronized void init( ServletConfig servletConfig ) throws ServletException {
    GatewayConfig gatewayConfig = (GatewayConfig) servletConfig.getServletContext().getAttribute(GatewayConfig.GATEWAY_CONFIG_ATTRIBUTE);
    isErrorMessageSanitizationEnabled = gatewayConfig.isErrorMessageSanitizationEnabled();
    errorMessageSanitizationPattern = gatewayConfig.getErrorMessageSanitizationPattern();
    try {
      if( filter == null ) {
        filter = createFilter( servletConfig );
      }
      filterConfig = new FilterConfigAdapter( servletConfig );
      if( filter != null ) {
        filter.init( filterConfig );
      }
    } catch( ServletException | RuntimeException e ) {
      throw logAndSanitizeException(e);
    }
  }

  // Compilation fails: java: unreported exception java.lang.Exception; must be caught or declared to be thrown
  private <T extends Exception> T logAndSanitizeException(Exception e)  {
    LOG.failedToExecuteFilter(e);
    return (T) sanitizeException(e);
  }

  // Compiles but tests fail. IntelliJ warns us that we don't have to declare that we throw T
  private <T extends Exception> T logAndSanitizeException(Exception e) throws T {
    LOG.failedToExecuteFilter(e);
    return (T) sanitizeException(e);
  }

 // this works
  private <T extends Exception> T logAndSanitizeException(Exception e) throws T {
    LOG.failedToExecuteFilter(e);
    throw (T) sanitizeException(e);
  }