ServletContextImpl.java 文件源码

@Override
public FilterRegistration.Dynamic addFilter(final String filterName, final String className) {
    ensureNotProgramaticListener();
    ensureNotInitialized();
    if (deploymentInfo.getFilters().containsKey(filterName)) {
        return null;
    }
    try {
        FilterInfo filter = new FilterInfo(filterName, (Class<? extends Filter>) deploymentInfo.getClassLoader().loadClass(className));
        deploymentInfo.addFilter(filter);
        deployment.getFilters().addFilter(filter);
        return new FilterRegistrationImpl(filter, deployment, this);
    } catch (ClassNotFoundException e) {
        throw UndertowServletMessages.MESSAGES.cannotLoadClass(className, e);
    }
}