handshake_failure

在java 1.6版本中，通过HttpsURLConnection请求class 1（多发生于免费ssl证书，比如沃通或者startssl的）的https网络地址时，可能会报握手异常：

Caused by: java.lang.RuntimeException: javax.net.ssl.SSLHandshakeException: Received fatal alert: handshake_failure
- Received fatal alert: handshake_failure
javax.net.ssl.SSLHandshakeException: Received fatal alert: handshake_failure
    at com.sun.net.ssl.internal.ssl.Alerts.getSSLException(Alerts.java:174)
    at com.sun.net.ssl.internal.ssl.Alerts.getSSLException(Alerts.java:136)
    at com.sun.net.ssl.internal.ssl.SSLSocketImpl.recvAlert(SSLSocketImpl.java:1822)
    at com.sun.net.ssl.internal.ssl.SSLSocketImpl.readRecord(SSLSocketImpl.java:1004)
    at com.sun.net.ssl.internal.ssl.SSLSocketImpl.performInitialHandshake(SSLSocketImpl.java:1188)
    at com.sun.net.ssl.internal.ssl.SSLSocketImpl.startHandshake(SSLSocketImpl.java:1215)
    at com.sun.net.ssl.internal.ssl.SSLSocketImpl.startHandshake(SSLSocketImpl.java:1199)
    at sun.net.www.protocol.https.HttpsClient.afterConnect(HttpsClient.java:434)
    at sun.net.www.protocol.https.AbstractDelegateHttpsURLConnection.connect(AbstractDelegateHttpsURLConnection.java:166)
    at sun.net.www.protocol.http.HttpURLConnection.getInputStream(HttpURLConnection.java:1195)
    at sun.net.www.protocol.https.HttpsURLConnectionImpl.getInputStream(HttpsURLConnectionImpl.java:234)

可以做如下尝试：

    /*
     * 在java1.6中，进行https的请求会提示 Received fatal alert: handshake_failure
     * 的握手失败的异常，网上的资料说这是个bug
     * 参考此贴http://www.coderanch.com/t/637177/Security/Disabling-handshake-message-Java 按照楼主处理， 把协议版本临时修改，再恢复的方式绕过了此bug
     */
    String defaultValue = System.getProperty("https.protocols");
    System.setProperty("https.protocols", "TLSv1");
    String response = CommonUtils.getResponseFromServer(url, "utf-8");//请求https地址
    log.debug("用户登陆过程正常:获得响应为" + response);

    if (defaultValue != null) {
        System.setProperty("https.protocols", defaultValue);
    } else {
        System.clearProperty("https.protocols");
    }