带有 sslSocketFactory 的 Okhttp.Builder 中的 ExceptionInInitializerError

Question

我正在开发一个项目，该项目需要将所有证书用于单个调用，每当我尝试设置 sslSocketFactory 时，我都会收到一个错误，指示 ExceptionInInitializerError。

我搜索了 SO 并找到了这个问题，但它没有为我解决问题；对于这个 Git 问题也是如此。

我的示例代码如下：

    X509TrustManager trustManager = new X509TrustManager() {
        public void checkClientTrusted(X509Certificate[] xcs, String string)
                throws CertificateException {}
        public void checkServerTrusted(X509Certificate[] xcs, String string)
                throws CertificateException {}
        public X509Certificate[] getAcceptedIssuers() {
            return null;
        }
    };
    SSLContext sslContext;
    SSLSocketFactory sslSocketFactory = null;
    try {
        sslContext = SSLContext.getInstance("TLS");
        sslContext.init(null, new TrustManager[]{trustManager}, null);
        sslSocketFactory = sslContext.getSocketFactory();
    } catch (Exception e){
        e.printStackTrace();
    }
    OkHttpClient client = new OkHttpClient.Builder().sslSocketFactory(sslSocketFactory,
            trustManager).addInterceptor(interceptor).build();

当发送的参数全部有效且不为空时，为什么我会收到错误？

Answer 1

事实证明，该问题是由 okhttp3 构建器方法内部调用 NullPointerException 引起的。确切的代码在这里：

Caused by: java.lang.NullPointerException: Attempt to get length of null array
        at okhttp3.internal.tls.BasicTrustRootIndex.<init>(BasicTrustRootIndex.java:32)
        at okhttp3.internal.platform.Platform.buildTrustRootIndex(Platform.java:288)
        at okhttp3.internal.platform.AndroidPlatform.buildTrustRootIndex(AndroidPlatform.java:280)
        at okhttp3.internal.platform.Platform.buildCertificateChainCleaner(Platform.java:172)
        at okhttp3.internal.platform.AndroidPlatform.buildCertificateChainCleaner(AndroidPlatform.java:230)
        at okhttp3.internal.tls.CertificateChainCleaner.get(CertificateChainCleaner.java:41)
        at okhttp3.OkHttpClient$Builder.sslSocketFactory(OkHttpClient.java:694)

这个问题的原因是我在 Stackoverflow（IE此处）上遵循了大量示例，这些示例告诉您使用该return null;行构建 x509 TrustManager。

解决方法是简单地更改一行：

    X509TrustManager trustManager = new X509TrustManager() {
        public void checkClientTrusted(X509Certificate[] xcs, String string)
                throws CertificateException {}
        public void checkServerTrusted(X509Certificate[] xcs, String string)
                throws CertificateException {}
        public X509Certificate[] getAcceptedIssuers() {
            //Here
            return new X509Certificate[]{};
        }
    };
    .
    .
    .

这解决了问题。