Java使用netty的HttpProxyHandler放入忽略地址，支持通配符*

在使用netty的HttpProxyHandler时，可以通过设置自定义的ProxyHandlerSelector来实现忽略地址的功能，具体步骤如下：

1. 创建一个自定义的ProxyHandlerSelector类，继承自DefaultProxyHandlerSelector类。

2. 在自定义的ProxyHandlerSelector类中重写select方法，在该方法中判断是否需要忽略当前请求的目标地址，如果需要忽略，则返回null，否则返回HttpProxyHandler。

3. 在创建Bootstrap时，通过调用handler方法设置自定义的ProxyHandlerSelector类。

下面是一个示例代码，演示如何使用通配符*来忽略地址：

import io.netty.bootstrap.Bootstrap;
import io.netty.channel.Channel;
import io.netty.channel.ChannelHandlerContext;
import io.netty.channel.ChannelInitializer;
import io.netty.channel.ChannelPipeline;
import io.netty.channel.SimpleChannelInboundHandler;
import io.netty.channel.socket.SocketChannel;
import io.netty.channel.socket.nio.NioSocketChannel;
import io.netty.handler.codec.http.DefaultHttpRequest;
import io.netty.handler.codec.http.FullHttpResponse;
import io.netty.handler.codec.http.HttpClientCodec;
import io.netty.handler.codec.http.HttpMethod;
import io.netty.handler.codec.http.HttpObjectAggregator;
import io.netty.handler.codec.http.HttpRequest;
import io.netty.handler.codec.http.HttpResponse;
import io.netty.handler.codec.http.HttpVersion;
import io.netty.handler.proxy.DefaultProxyHandlerSelector;
import io.netty.handler.proxy.ProxyHandler;
import io.netty.handler.proxy.ProxyHandlerSelector;
import io.netty.handler.proxy.Socks5ProxyHandler;
import io.netty.handler.proxy.Socks4ProxyHandler;
import io.netty.handler.proxy.Socks4aProxyHandler;
import io.netty.handler.proxy.Socks5AddressEncoder;
import io.netty.handler.proxy.Socks5CommandRequest;
import io.netty.handler.proxy.Socks5InitialRequest;
import io.netty.handler.proxy.Socks5InitialResponse;
import io.netty.handler.proxy.Socks5ProxyHandler;
import io.netty.handler.proxy.Socks5ProxyServerDecoder;
import io.netty.handler.proxy.Socks5ProxyServerEncoder;
import io.netty.handler.ssl.SslContext;
import io.netty.handler.ssl.SslContextBuilder;
import io.netty.handler.ssl.SslProvider;
import io.netty.handler.ssl.util.InsecureTrustManagerFactory;

import java.net.InetSocketAddress;
import java.net.URI;

public class NettyHttpProxy {

    private static final String PROXY_HOST = "127.0.0.1";
    private static final int PROXY_PORT = 1080;

    public static void main(String[] args) throws Exception {
        URI uri = new URI("https://www.google.com");
        String host = uri.getHost();
        int port = uri.getPort() == -1 ? 443 : uri.getPort();

        Bootstrap bootstrap = new Bootstrap();
        bootstrap.group(new NioEventLoopGroup())
                .channel(NioSocketChannel.class)
                .handler(new ChannelInitializer<SocketChannel>() {
                    @Override
                    protected void initChannel(SocketChannel ch) throws Exception {
                        ChannelPipeline pipeline = ch.pipeline();
                        if (uri.getScheme().equalsIgnoreCase("https")) {
                            SslContext sslContext = SslContextBuilder.forClient().sslProvider(SslProvider.JDK)
                                    .trustManager(InsecureTrustManagerFactory.INSTANCE).build();
                            pipeline.addFirst(sslContext.newHandler(ch.alloc(), host, port));
                        }
                        ProxyHandlerSelector selector = new MyProxyHandlerSelector();
                        ProxyHandler proxyHandler = new HttpProxyHandler(new InetSocketAddress(PROXY_HOST, PROXY_PORT), selector);
                        pipeline.addLast(proxyHandler);
                        pipeline.addLast(new HttpClientCodec());
                        pipeline.addLast(new HttpObjectAggregator(1024 * 1024));
                        pipeline.addLast(new SimpleChannelInboundHandler<HttpResponse>() {
                            @Override
                            protected void channelRead0(ChannelHandlerContext ctx, HttpResponse msg) throws Exception {
                                System.out.println(msg.toString());
                            }
                        });
                    }
                });

        Channel channel = bootstrap.connect(host, port).sync().channel();
        HttpRequest request = new DefaultHttpRequest(HttpVersion.HTTP_1_1, HttpMethod.GET, uri.getRawPath());
        request.headers().set("Host", host);
        request.headers().set("Connection", "close");
        request.headers().set("User-Agent", "netty-tcp-client");
        channel.writeAndFlush(request).sync();
        channel.closeFuture().sync();
    }

    private static class MyProxyHandlerSelector extends DefaultProxyHandlerSelector {
        private static final String[] IGNORED_HOSTS = new String[]{"*.google.com"};

        @Override
        public ProxyHandler select(URI uri) {
            String host = uri.getHost();
            for (String ignoredHost : IGNORED_HOSTS) {
                if (host.matches(ignoredHost.replace("*", ".*"))) {
                    return null;
                }
            }
            return super.select(uri);
        }
    }

}

在上面的示例代码中，我们定义了一个MyProxyHandlerSelector类来实现忽略地址的功能。在该类中，我们使用IGNORED_HOSTS数组来指定需要忽略的目标地址，每个地址可以使用通配符*来表示任意字符。然后在select方法中，我们遍历IGNORED_HOSTS数组，如果当前请求的目标地址匹配到了需要忽略的地址，则返回null，否则返回HttpProxyHandler。最后，在创建Bootstrap时，我们通过调用handler方法设置自定义的ProxyHandlerSelector类。