Question

我正在开发一个Java Web服务应用程序（使用JAX-WS），它必须使用两个不同的代理来建立与Internet和Intranet的分离连接。作为解决方案，我尝试编写自己的 java.net.ProxySelector ，为Internet或Intranet返回 java.net.Proxy 实例（HTTP类型）。

在一个小测试应用程序中，我尝试通过 URL.openConnection（）下载网页，然后我用我自己的替换默认的ProxySelector。但它导致例外：

java.net.SocketException：未知代理类型：HTTP 在java.net.SocksSocketImpl.connect（SocksSocketImpl.java:370）在java.net.Socket.connect（Socket.java:519）在java.net.Socket.connect（Socket.java:469）在sun.net.NetworkClient.doConnect（NetworkClient.java:163）在sun.net.www.http.HttpClient.openServer(HttpClient.java:394）在sun.net.www.http.HttpClient.openServer（HttpClient.java:529）在sun.net.www.http.HttpClient。（HttpClient.java:233）在sun.net.www.http.HttpClient.New（HttpClient.java:306）在sun.net.www.protocol.http.HttpURLConnection.getNewHttpClient（HttpURLConnection.java:844）在sun.net.www.protocol.http.HttpURLConnection.plainConnect（HttpURLConnection.java:792）在sun.net.www.protocol.http.HttpURLConnection.connect（HttpURLConnection.java:703） at sun.net.www.protocol.http.HttpURLConnection.getInputStream（HttpURLConnection.java:1026）在java.net.HttpURLConnection.getResponseCode（HttpURLConnection.java:373） at norman.test.ProxyTest.conntectToRmViaProxy（ProxyTest.java:42）在norman.test.ProxyTest.main（ProxyTest.java:65）

问题：“如果我的ProxySelector仅返回HTTP代理，为什么尝试通过SOCKS建立连接？”

2问题：“是否有替代方案，为每个连接定义不同的代理？”

这是我的ProxySelector：

public class OwnProxySelector extends ProxySelector {
private Proxy intranetProxy;
private Proxy extranetProxy;
private Proxy directConnection = Proxy.NO_PROXY;
private URI intranetAddress;
private URI extranetAddress;

/* (non-Javadoc)
 * @see java.net.ProxySelector#connectFailed(java.net.URI, java.net.SocketAddress, java.io.IOException)
 */
public void connectFailed(URI uri, SocketAddress sa, IOException ioe) {
    // Nothing to do
}

/* (non-Javadoc)
 * @see java.net.ProxySelector#select(java.net.URI)
 */
public List select(URI uri) {
    ArrayList<Proxy> result = new ArrayList<Proxy>();

    if(intranetAddress.getHost().equals(uri.getHost()) && intranetAddress.getPort()==uri.getPort()){
        result.add(intranetProxy);
        System.out.println("Adding intranet Proxy!");
    }
    else if(extranetAddress.getHost().equals(uri.getHost()) && extranetAddress.getPort()==uri.getPort()){
        result.add(extranetProxy);
        System.out.println("Adding extranet Proxy!");
    }
    else{
        result.add(directConnection);
        System.out.println("Adding direct connection!");
    }

    return result;
}

public void setIntranetProxy(String proxyAddress, int proxyPort){
    if(proxyAddress==null || proxyAddress.isEmpty()){
        intranetProxy = Proxy.NO_PROXY;
    }
    else{
        SocketAddress address = new InetSocketAddress(proxyAddress, proxyPort);
        intranetProxy = new Proxy(Proxy.Type.HTTP, address);
    }
}

public void setExtranetProxy(String proxyAddress, int proxyPort){
    if(proxyAddress==null || proxyAddress.isEmpty()){
        extranetProxy = Proxy.NO_PROXY;
    }
    else{
        SocketAddress address = new InetSocketAddress(proxyAddress, proxyPort);
        extranetProxy = new Proxy(Proxy.Type.HTTP, address);
    }
}

public void clearIntranetProxy(){
    intranetProxy = Proxy.NO_PROXY;
}

public void clearExtranetProxy(){
    extranetProxy = Proxy.NO_PROXY;
}

public void setIntranetAddress(String address) throws URISyntaxException{
    intranetAddress = new URI(address);
}

public void setExtranetAddress(String address) throws URISyntaxException{
    extranetAddress = new URI(address);
}
}

这是测试类：

public class ProxyTest {
OwnProxySelector ownSelector = new OwnProxySelector();

public ProxyTest(){
    ownSelector.setIntranetProxy("intranet.proxy", 8123);
    try {
        ownSelector.setIntranetAddress("http://intranet:80");
    } catch (URISyntaxException e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
    }

    ownSelector.setExtranetProxy("", 0);
    try {
        ownSelector.setExtranetAddress("http://www.example.com:80");
    } catch (URISyntaxException e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
    }


    ProxySelector.setDefault(ownSelector);
}

public void conntectToRmViaProxy(boolean internal, String connectAddress){
    try {
        URL url = new URL(connectAddress);

        HttpURLConnection conn = (HttpURLConnection)url.openConnection();

        conn.setRequestMethod("GET");
          if (conn.getResponseCode() != HttpURLConnection.HTTP_OK) {
            System.out.println(conn.getResponseMessage());
          }
          else{
              BufferedReader reader = new BufferedReader(new InputStreamReader(conn.getInputStream()));
              int tmp = reader.read();
              while(tmp != -1){
                  System.out.print((char)tmp);
                  tmp = reader.read();
              }
          }

    } catch (MalformedURLException e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
    } catch (IOException e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
    }
}

public static void main(String[] args){
    ProxyTest proxyText = new ProxyTest();
    proxyText.conntectToRmViaProxy(true, "http://intranet:80");
}
}

Answer 1

好的，我发现了问题。

如果请求的URL不包含端口，HttpURLConnection会执行两次OwnProxySelector.select（）。

首先，HttpURLConnection使用URI调用select（），其Scheme为“http”但没有端口。 select（）检查主机地址和端口是否与intranetAddress或extranetAddress相同。这不匹配，因为没有给出端口。因此，选择返回代理以进行直接连接。

在第二个HttpURLConnection调用带有URI的select（），方案为“socket”和端口80.因此，因为select（）检查主机地址和端口，而不是方案，它返回了一个HTTP代理

现在这是我更正的OwnProxySelector版本。它检查方案并设置HTTP或HTTPS的默认端口（如果URI未给出端口）。如果没有给出HTTP或HTTPS方案，它也会询问Java标准ProxySelector。

public class OwnProxySelector extends ProxySelector {
private ProxySelector defaultProxySelector;
private Proxy intranetProxy;
private Proxy extranetProxy;
private Proxy directConnection = Proxy.NO_PROXY;
private URI intranetAddress;
private URI extranetAddress;


public OwnProxySelector(ProxySelector defaultProxySelector){
    this.defaultProxySelector = defaultProxySelector;
}

/* (non-Javadoc)
 * @see java.net.ProxySelector#connectFailed(java.net.URI, java.net.SocketAddress, java.io.IOException)
 */
public void connectFailed(URI uri, SocketAddress sa, IOException ioe) {
    // Nothing to do
}

/* (non-Javadoc)
 * @see java.net.ProxySelector#select(java.net.URI)
 */
public List select(URI uri) {
    ArrayList<Proxy> result = new ArrayList<Proxy>();

    if(uri.getScheme().equalsIgnoreCase("http") || uri.getScheme().equalsIgnoreCase("https")){
        int uriPort = uri.getPort();

        // set default http and https ports if port is not given in URI
        if(uriPort<1){
            if(uri.getScheme().equalsIgnoreCase("http")){
                uriPort = 80;
            }
            else if(uri.getScheme().equalsIgnoreCase("http")){
                uriPort = 443;
            }
        }

        if(intranetAddress.getHost().equals(uri.getHost()) && intranetAddress.getPort()==uriPort){
            result.add(intranetProxy);
            System.out.println("Adding intranet Proxy!");
        }
        else if(extranetAddress.getHost().equals(uri.getHost()) && extranetAddress.getPort()==uriPort){
            result.add(extranetProxy);
            System.out.println("Adding extranet Proxy!");
        }
    }

    if(result.isEmpty()){
        List<Proxy> defaultResult = defaultProxySelector.select(uri);
        if(defaultResult!=null && !defaultResult.isEmpty()){
            result.addAll(defaultResult);
            System.out.println("Adding Proxis from default selector.");
        }
        else{
            result.add(directConnection);
            System.out.println("Adding direct connection, because requested URI does not match any Proxy");
        }
    }

    return result;
}

public void setIntranetProxy(String proxyAddress, int proxyPort){
    if(proxyAddress==null || proxyAddress.isEmpty()){
        intranetProxy = Proxy.NO_PROXY;
    }
    else{
        SocketAddress address = new InetSocketAddress(proxyAddress, proxyPort);
        intranetProxy = new Proxy(Proxy.Type.HTTP, address);
    }
}

public void setExtranetProxy(String proxyAddress, int proxyPort){
    if(proxyAddress==null || proxyAddress.isEmpty()){
        extranetProxy = Proxy.NO_PROXY;
    }
    else{
        SocketAddress address = new InetSocketAddress(proxyAddress, proxyPort);
        extranetProxy = new Proxy(Proxy.Type.HTTP, address);
    }
}

public void clearIntranetProxy(){
    intranetProxy = Proxy.NO_PROXY;
}

public void clearExtranetProxy(){
    extranetProxy = Proxy.NO_PROXY;
}

public void setIntranetAddress(String address) throws URISyntaxException{
    intranetAddress = new URI(address);
}

public void setExtranetAddress(String address) throws URISyntaxException{
    extranetAddress = new URI(address);
}

}

但我很好奇，HttpURLConnection在第一次调用时得到了一个直接连接代理时，第二次调用了select（）。

将不同的代理连接到特定地址

1 个答案: