Bucket.get() throws null pointer exception

Java SDK
4

the NullPointerException happens because when you build your Customer you call fDoc.content() but fDoc is null.
What you can do is:

public Customer findCustomerDocId(String docId) throws NullPointerException{
    Gson gson = new GsonBuilder().create();
    JsonDocument fDoc = theBucket.get(docId);
    if (fDoc == null) {
        //create the content. JSON String?
        String newContent;
       //create the doc and store
       RawJsonDocument newDoc = RawJsonDocument.create(docId, newContent);
       theBucket.insert(newDoc);
       //you should have also a Customer object at this point, to return
       return ???;
    } else {
        Customer cust = gson.fromJson(fDoc.content().toString(), Customer.class);
        return cust;
    }
}