java每个线程都使用自己的代理

Question

我正在尝试设置一个Java程序，其中每个线程都可以使用自己的代理

现在我只找到了一种全局设置代理的方法。（http://docs.oracle.com/javase/6/docs/technotes/guides/net/proxies.html）

As mentioned earlier, these settings affect all http connections during the entire lifetime of the VM invoked with these options. However it is possible, using the System.setProperty() method, to have a slightly more dynamic behavior.

Here is a code excerpt showing how this can be done:

//Set the http proxy to webcache.mydomain.com:8080

System.setProperty("http.proxyHost", "webcache.mydomain.com"); System.setPropery("http.proxyPort", "8080");

更新

我尝试使用proxy类，但当我不想使用所述代理时，无法创建直接连接：

private void setProxy()
{
    if(proxyUrl != null)
    {
        SocketAddress addr = new InetSocketAddress(proxyUrl, proxyPort);
        proxy = new Proxy(Proxy.Type.HTTP, addr);
    }
    else
    {
        proxy = new Proxy(Proxy.Type.DIRECT, null);
    }       
}

Exception in .... java.lang.IllegalArgumentException: type DIRECT is not compatible with address null

我怎样才能让这个直接连接工作？还没有试过代理

Answer 1

Barry NL的解决方案是半有效的，因为我不知道如何在该解决方案中不使用代理

我想到的是：

proxyUrl和proxyPort在我的类的构造函数中

如果我只设置了^{，我就无法调用url.openConnection(proxy);

或者proxy = new Proxy(Proxy.Type.DIRECT, null);。 所以我写了我自己的openConnection

private void setProxy()
{
    if(proxyUrl != null)
    {
        SocketAddress addr = new InetSocketAddress(proxyUrl, proxyPort);
        proxy = new Proxy(Proxy.Type.HTTP, addr);
    }
    else
    {
        proxy = null;
    }       
}
private URLConnection openConnection2(URL url)
{
    try {
        if(proxy != null)               
            return url.openConnection(proxy);               
        else 
            return url.openConnection();            
    } catch (IOException e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
        return null;
    }   
}

在建立任何连接之前必须调用setProxy()

我也换了

url = new URL(http_url);
con = (HttpURLConnection)url.openConnection(proxy);

与

url = new URL(http_url);
con = (HttpURLConnection)openConnection2(url);  

Answer 2

可以使用第3节中解释的Proxy类here：

As we have seen, the system properties are powerful, but not flexible. The "all or nothing" behavior was justly deemed too severe a limitation by most developers. That's why it was decided to introduce a new, more flexible, API in J2SE 5.0 so that it would be possible to have connection based proxy settings.

你可以使用Proxy.NO_PROXY来：

... not to use any proxying.

这样做：

private void setProxy()
{
    if(proxyUrl != null)
    {
        SocketAddress addr = new InetSocketAddress(proxyUrl, proxyPort);
        proxy = new Proxy(Proxy.Type.HTTP, addr);
    }
    else
    {
        proxy = Proxy.NO_PROXY;
    }       
}