测试协议

public static void main(String[] args) throws Exception {
		SSLContext context = SSLContext.getInstance("TLS");
		context.init(null, null, null);
 
		SSLSocketFactory factory = (SSLSocketFactory) context.getSocketFactory();
		SSLSocket socket = (SSLSocket) factory.createSocket();
 
		String[] protocols = socket.getSupportedProtocols();// 支持的协议名称的数组
		
		System.out.println("Supported Protocols: " + protocols.length);
		for (int i = 0; i < protocols.length; i++) {
			System.out.println(" " + protocols[i]);
		}
 
		protocols = socket.getEnabledProtocols();
 
		System.out.println("Enabled Protocols: " + protocols.length);// 返回由此工厂创建的服务器套接字所接受的 ssl 连接上启用的协议版本的名称，如果此工厂使用默认启用的协议版本，则返回 null。
		for (int i = 0; i < protocols.length; i++) {
			System.out.println(" " + protocols[i]);
		}
 
	}

Supported Protocols: 5
 SSLv2Hello
 SSLv3
 TLSv1
 TLSv1.1
 TLSv1.2
Enabled Protocols: 3
 TLSv1
 TLSv1.1
 TLSv1.2

jdk7:默认支持 TLSv1

jdk8:默认支持 TLSv1.2