如何在Java中使用TLSV1或SSLV3进行第一次握手（Client Hello）？

当我执行以下代码时，为什么第一次握手是SSLv2，而不是TLSv1或SSLv3？

如何在Java中使用TLSV1或SSLV3进行第一次握手？

String host = "www.google.com";
String url = "/adsense/?sourceid=aso&subid=ZH_CN-ET-AS-ADSBY6&medium=link&hl=zh_CN";
SSLContext ctx = SSLContext.getInstance("TLS");
ctx.init(new KeyManager[0], new TrustManager[] {new DefaultTrustManager()}, new SecureRandom());
SSLContext.setDefault(ctx);
SSLSocketFactory factory = ctx.getSocketFactory();
Socket socket = factory.createSocket(host, 443);
BufferedWriter out = new BufferedWriter(new OutputStreamWriter(socket.getOutputStream()));
BufferedReader in = new BufferedReader(new InputStreamReader(socket.getInputStream()));
out.write("GET " + url + " HTTP/1.0");
out.flush();
out.close();
in.close();

对于 TLSv1： 启动客户端 jvm

-Dhttps.protocols="TLSv1" 

or using

System.setProperty("https.protocols", "TLSv1");

为我解决了问题。