下载https图片工具类

普通http工具类httpClient 访问https图片会报以下错误

javax.net.ssl.SSLHandshakeException: java.security.cert.CertificateException: No subject alternative names present
at sun.security.ssl.Alerts.getSSLException(Alerts.java:192)
at sun.security.ssl.SSLSocketImpl.fatal(SSLSocketImpl.java:1949)
at sun.security.ssl.Handshaker.fatalSE(Handshaker.java:302)
at sun.security.ssl.Handshaker.fatalSE(Handshaker.java:296)
at sun.security.ssl.ClientHandshaker.serverCertificate(ClientHandshaker.java:1514)
at sun.security.ssl.ClientHandshaker.processMessage(ClientHandshaker.java:216)
at sun.security.ssl.Handshaker.processLoop(Handshaker.java:1026)
at sun.security.ssl.Handshaker.process_record(Handshaker.java:961)
at sun.security.ssl.SSLSocketImpl.readRecord(SSLSocketImpl.java:1062)
at sun.security.ssl.SSLSocketImpl.performInitialHandshake(SSLSocketImpl.java:1375)
at sun.security.ssl.SSLSocketImpl.startHandshake(SSLSocketImpl.java:1403)
at sun.security.ssl.SSLSocketImpl.startHandshake(SSLSocketImpl.java:1387)
at sun.net.www.protocol.https.HttpsClient.afterConnect(HttpsClient.java:559)
at sun.net.www.protocol.https.AbstractDelegateHttpsURLConnection.connect(AbstractDelegateHttpsURLConnection.java:185)
at sun.net.www.protocol.http.HttpURLConnection.getInputStream0(HttpURLConnection.java:1546)
at sun.net.www.protocol.http.HttpURLConnection.getInputStream(HttpURLConnection.java:1474)
at sun.net.www.protocol.https.HttpsURLConnectionImpl.getInputStream(HttpsURLConnectionImpl.java:254)

使用此工具类，忽略证书提示，可以下载到https图片

static TrustManager[] trustAllCerts = new TrustManager[]{new X509TrustManager() {
    @Override
    public void checkClientTrusted(X509Certificate[] chain, String authType) throws CertificateException {
    }

    @Override
    public void checkServerTrusted(X509Certificate[] chain, String authType) throws CertificateException {
    }

    @Override
    public X509Certificate[] getAcceptedIssuers() {
        return null;
    }
}};

static class NullHostNameVerifier implements HostnameVerifier {
    @Override
    public boolean verify(String arg0, SSLSession arg1) {
        return true;
    }
}

/**
 * 获取https图片,兼容http地址图片
 *
 * @param imageUrl
 */
public static InputStream imageFromUrlByHttps(String imageUrl) {
    //new一个URL对象
    URL url = null;
    try {
        HttpsURLConnection.setDefaultHostnameVerifier(new NullHostNameVerifier());
        SSLContext sc = SSLContext.getInstance("TLS");
        sc.init(null, trustAllCerts, new SecureRandom());
        HttpsURLConnection.setDefaultSSLSocketFactory(sc.getSocketFactory());
        url = new URL(imageUrl);
        //打开链接
        HttpURLConnection conn = (HttpURLConnection) url.openConnection();
        //设置请求方式为"GET"
        conn.setRequestMethod("GET");
        //超时响应时间为5秒
        conn.setConnectTimeout(5 * 1000);
        //通过输入流获取图片数据
        InputStream inStream = conn.getInputStream();
        //得到图片的二进制数据，以二进制封装得到数据，具有通用性
        byte[] data = readInputStream(inStream);
        // 直接返回图片数据流
        return new ByteArrayInputStream(data);
        
        //或者 写文件保存图片
        //File imageFile = new File(savePath);
        //创建输出流
        //FileOutputStream outStream = new FileOutputStream(imageFile);
        //写入数据
        //outStream.write(data);
        //关闭输出流
        //outStream.close();
    } catch (Exception e) {
        log.error("读取https地址图片失败！", e);
    }
    return null;
}