import io.undertow.server.handlers.ResponseCodeHandler; //导入依赖的package包/类
@Override
public void handleRequest(HttpServerExchange exchange) throws Exception {
    if (Methods.POST.equals(exchange.getRequestMethod()))  {
        ResponseCodeHandler.HANDLE_405.handleRequest(exchange);
        return;
    }
    String origReqPath = exchange.getRelativePath();
    String remapped = remapper.remapPath(origReqPath);
    if (remapped == null) {
        ResponseCodeHandler.HANDLE_404.handleRequest(exchange);
        return;
    }
    exchange.setRelativePath(remapped);

    // Note: we only change the relative path, not other exchange data that
    // incorporates it (like getRequestPath(), getRequestURL()) and not the
    // resolved path. If this request gets to DomainApiHandler, it should
    // work off the relative path. Other handlers in between may need the
    // original data.

    next.handleRequest(exchange);
}
 

import io.undertow.server.handlers.ResponseCodeHandler; //导入依赖的package包/类
@Override
public HandlerWrapper build(final Map<String, Object> config) {
    final Integer value = (Integer) config.get("value");
    return new HandlerWrapper() {
        @Override
        public HttpHandler wrap(HttpHandler handler) {
            return new ResponseCodeHandler(value);
        }
    };
}
 

import io.undertow.server.handlers.ResponseCodeHandler; //导入依赖的package包/类
/**
 * Returns a handler that can act as a load balancing reverse proxy.
 *
 * @param proxyClient The proxy client to use to connect to the remote server
 * @return The proxy handler
 */
public static ProxyHandler proxyHandler(ProxyClient proxyClient) {
    return new ProxyHandler(proxyClient, ResponseCodeHandler.HANDLE_404);
}
 

import io.undertow.server.handlers.ResponseCodeHandler; //导入依赖的package包/类
/**
 * Create a new {@link WebSocketProtocolHandshakeHandler}
 *
 * @param callback The {@link WebSocketConnectionCallback} which will be executed once the handshake was
 *                 established
 */
public WebSocketProtocolHandshakeHandler(final WebSocketConnectionCallback callback) {
    this(callback, ResponseCodeHandler.HANDLE_404);
}