CODEWITHSUNDEEP
androidnullpointerexceptionwebsocketfirebase
Ashok Varma
Ashok Varma

Reputation: 3539

Firebase crash due to null pointer exception

Firebase null pointer exception. Attached stacktrace down below

Fatal Exception: java.lang.NullPointerException: Attempt to invoke virtual method 'java.lang.String java.lang.String.toLowerCase(java.util.Locale)' on a null object reference
       at com.firebase.tubesock.WebSocketHandshake.verifyServerHandshakeHeaders(WebSocketHandshake.java:96)
       at com.firebase.tubesock.WebSocket.runReader(WebSocket.java:365)
       at com.firebase.tubesock.WebSocket.access$000(WebSocket.java:30)
       at com.firebase.tubesock.WebSocket$2.run(WebSocket.java:108)
       at java.lang.Thread.run(Thread.java:818)

Version : latest (2.5.2+) as of 3-may-2016

Device Details : LGE - lgls770 running android 6.0 and Non-Rooted

Upvotes: 16

Views: 1726

Answers (2)

Shafqat Kamal
Shafqat Kamal

Reputation: 439

If you are using the previous version of firebase then update your library version of firebase.

In my case i was using the the firebase analytics 

compile 'com.google.android.gms:play-services-analytics:9.8.0'

Then I updated that with

compile 'com.google.android.gms:play-services-analytics:10.2.4'

Everything is now working fine in my case.still if you have problem let me know.

if my answer will help you then don't forgot to increase my answer vote.

Upvotes: 4

Takahiko Kawasaki
Takahiko Kawasaki

Reputation: 19001

The code snippet below is the implementation of verifyServerhandshakeHeaders method found in WebSocketHandshake.java.

public void verifyServerHandshakeHeaders(HashMap<String, String> headers) {
    if (!headers.get("Upgrade").toLowerCase(Locale.US).equals("websocket")) {
        throw new WebSocketException("connection failed: missing header field in server handshake: Upgrade");
    } else if (!headers.get("Connection").toLowerCase(Locale.US).equals("upgrade")) {
        throw new WebSocketException("connection failed: missing header field in server handshake: Connection");
    }
}

As you can see, if the server does not include an Upgrade HTTP header in the response of the opening handshake (RFC 6455, 4. Opening Handshake), this code throws NullPointerException.

In addition, because the headers instance given to this method is created by new HashMap<String, String>() (WebSocket.java:360), HTTP headers sent from the server must be case-sensitive although the HTTP specification says "Field names are case-insensitive" (RFC 2616, 4.2 Message Headers). Therefore, for example, if a server sends an Upgrade HTTP header in all capital letters like UPGRADE, TubeSock throws NullPointerException although the server's behavior is correct.

headers instance should be created by

new TreeMap<String, List<String>>(String.CASE_INSENSITIVE_ORDER)

as I pointed out at a certain place.

TubeSock's WebSocket implementation does not even verify Sec-WebSocket-Accept header although the verification is required by RFC 6455. See RFC 6455, 4.1. Client Requirements for details.

Upvotes: 4

Related Questions