cas登入換用 jdk1.6 報錯handshake_failure握手失敗

用cas程式碼搭建demo，jdk版本為1.6，結果報錯javax.net.ssl.SSLHandshakeException: Received fatal alert: handshake_failure。
總結百度搜索答案：

1. 替換jdk的jar包，即jre\lib\security的local_policy.jar，US_export_policy.jar檔案替換掉（jre和jdk中的jre均替換掉），下載地址
   http://www.oracle.com/technetwork/java/javase/downloads/jce8-download-2133166.html；
2. 設定引數System.setProperty(“https.protocols”, “TLSv1.2,TLSv1.1,SSLv3”)；

試用過第一種，沒有解決問題；開始嘗試第二種，首先要找到引數新增地址，觀察報錯：

標明cas.client.util.Commonutils.getResponseFromServer 報錯，所以在建立客戶端與服務端建立連線時要指定jdk1.6的證書型別，經查證：

故程式碼設定為 System.setProperty(“https.protocols”, “TLSv1,SSLv3”);即

    public static String getResponseFromServer(final URL constructedUrl, final HostnameVerifier hostnameVerifier, final String encoding) {
    	URLConnection conn = null;
        try {
        	//加入支援證書型別
            System.setProperty("https.protocols", "TLSv1,SSLv3");
            conn = constructedUrl.openConnection();
            if (conn instanceof HttpsURLConnection) {
                ((HttpsURLConnection)conn).setHostnameVerifier(hostnameVerifier);
            }
            final BufferedReader in;
            if (CommonUtils.isEmpty(encoding)) {
                in = new BufferedReader(new InputStreamReader(conn.getInputStream()));
            } else {
                in = new BufferedReader(new InputStreamReader(conn.getInputStream(), encoding));
            }

            String line;
            final StringBuilder stringBuffer = new StringBuilder(255);

            while ((line = in.readLine()) != null) {
                stringBuffer.append(line);
                stringBuffer.append("\n");
            }
            return stringBuffer.toString();
        } catch (final Exception e) {
            LOG.error(e.getMessage(), e);
            throw new RuntimeException(e);
        } finally {
            if (conn != null && conn instanceof HttpURLConnection) {
                ((HttpURLConnection)conn).disconnect();
            }
        }

}
 

重啟專案，登入成功。

jdk證書型別部分參考https://blog.csdn.net/tawlang/article/details/80655460；
做一個備忘錄，若有不準確還望指正。