private void checkParameters(File lexFile) throws MojoExecutionException {
  if (lexFile == null) {
    throw new MojoExecutionException("<lexDefinition> is empty. Please define input file with <lexDefinition>input.jflex</lexDefinition>");
  }
  assert lexFile.isAbsolute() : lexFile;
  if (!lexFile.isFile()) {
    throw new MojoExecutionException("Input file does not exist: " + lexFile);
  }
}

private void checkParameters ( File lexFile ) throws MojoExecutionException { if ( lexFile == null ) { throw new MojoExecutionException ( "<lexDefinition> is empty. Please define input file with <lexDefinition>input.jflex</lexDefinition>" ) ; } assert lexFile . isAbsolute ( ) : lexFile ; if ( ! lexFile . isFile ( ) ) { throw new MojoExecutionException ( "Input file does not exist: " + lexFile ) ; } }
check parameter lexfile . must not be null and file must exist .
