How to catch this exception in Android webview?

Question

Due to a bug in Android 4.3, my app crashes when trying to load certain webpages in webview

The stack trace is like this:

09-16 14:16:48.221: E/AndroidRuntime(22487): FATAL EXCEPTION: WebViewCoreThread
09-16 14:16:48.221: E/AndroidRuntime(22487): java.lang.StringIndexOutOfBoundsException: length=0; index=-1
09-16 14:16:48.221: E/AndroidRuntime(22487):    at java.lang.AbstractStringBuilder.indexAndLength(AbstractStringBuilder.java:212)
09-16 14:16:48.221: E/AndroidRuntime(22487):    at java.lang.AbstractStringBuilder.charAt(AbstractStringBuilder.java:206)
09-16 14:16:48.221: E/AndroidRuntime(22487):    at java.lang.StringBuffer.charAt(StringBuffer.java:346)
09-16 14:16:48.221: E/AndroidRuntime(22487):    at com.android.org.bouncycastle.asn1.x509.X509NameTokenizer.nextToken(X509NameTokenizer.java:78)
09-16 14:16:48.221: E/AndroidRuntime(22487):    at com.android.org.bouncycastle.asn1.x509.X509Name.<init>(X509Name.java:719)
09-16 14:16:48.221: E/AndroidRuntime(22487):    at com.android.org.bouncycastle.asn1.x509.X509Name.<init>(X509Name.java:655)
09-16 14:16:48.221: E/AndroidRuntime(22487):    at com.android.org.bouncycastle.asn1.x509.X509Name.<init>(X509Name.java:593)
09-16 14:16:48.221: E/AndroidRuntime(22487):    at android.net.http.SslCertificate$DName.<init>(SslCertificate.java:379)
09-16 14:16:48.221: E/AndroidRuntime(22487):    at android.net.http.SslCertificate.<init>(SslCertificate.java:189)
09-16 14:16:48.221: E/AndroidRuntime(22487):    at android.net.http.SslCertificate.<init>(SslCertificate.java:178)
09-16 14:16:48.221: E/AndroidRuntime(22487):    at android.webkit.BrowserFrame.setCertificate(BrowserFrame.java:1206)
09-16 14:16:48.221: E/AndroidRuntime(22487):    at android.webkit.JWebCoreJavaBridge.nativeServiceFuncPtrQueue(Native Method)
09-16 14:16:48.221: E/AndroidRuntime(22487):    at android.webkit.JWebCoreJavaBridge.handleMessage(JWebCoreJavaBridge.java:113)
09-16 14:16:48.221: E/AndroidRuntime(22487):    at android.os.Handler.dispatchMessage(Handler.java:99)
09-16 14:16:48.221: E/AndroidRuntime(22487):    at android.os.Looper.loop(Looper.java:137)
09-16 14:16:48.221: E/AndroidRuntime(22487):    at android.webkit.WebViewCore$WebCoreThread.run(WebViewCore.java:814)
09-16 14:16:48.221: E/AndroidRuntime(22487):    at java.lang.Thread.run(Thread.java:841)

In my webview I have onReceivedSslError, and onReceivedError methods overridden but none of them is able to catch this exception.

try{
    webview.postUrl(url, EncodingUtils.getBytes(data, "BASE64"));
}
catch(Exception e){
    System.out.println("Caught the exception!");
}

surrounding the call to postUrl with a try/catch block (as above) also doesn't catch the exception.

Is there any way to catch this exception so that I can display a meaningful error message instead of letting the app crash?

Answer 1

You may have to try setting up a global uncaught exception handler. You do this by extending Application and defining the uncaught exception handler within there. It would look something like this:

public class MyApplication extends Application {

    @Override
    public void onCreate() {
        super.onCreate();

        Thread.setDefaultUncaughtExceptionHandler(new Thread.UncaughtExceptionHandler() {
            @Override
            public void uncaughtException(Thread thread, final Throwable ex) {
                // Custom code here to handle the error.
            }
        });
    }

}

Just make sure you point to your custom Application class in your Manifest.
Give that a shot. hope it helps.