工欲善其事

1.可以配置jvm虚拟机代理

java  -Dhttp.proxyHost=192.168.0.1  -Dhttp.proxyPort=80 MyJavaApp

2.配置系统代理

Properties prop = System.getProperties();   	  
prop.put("http.proxyHost","192.168.0.1");   		  
prop.put("http.proxyPort","80");

或

System.setProperty("proxyType", "4");
System.setProperty("proxyPort", "80"));
System.setProperty("proxyHost", "127.0.0.1");
System.setProperty("proxySet", "true");

3.配置URLConnection代理

Proxy proxy = new Proxy(Proxy.Type.HTTP, new InetSocketAddress("123.0.0.1", 8080));
URL url = new URL("http://www.yahoo.com");
HttpURLConnection uc = (HttpURLConnection)url.openConnection(proxy);
uc.connect();
  
String page;
StringBuffer tmp = new StringBuffer();
BufferedReader in = new BufferedReader(new InputStreamReader(uc.getInputStream()));
while ((line = in.readLine()) != null){
   page.append(line + "\n");
}
System.out.println(page);

第二种用过其它两种没有用，感觉第一种更灵活一些