使用java playframework在heroku中的應用程序錯誤

Question

我正在嘗試在Heroku中發布Play框架應用程序。 我按照這里的說明進行操作。 我也有以下依賴項

   java
   play framework 1.2.4
   mongolab
   morphia 1.6.2a

當我使用commang“heroku open”在heroku中打開應用程序時。 它顯示錯誤如下..，

Oops, an error occured

This exception has been logged with id 6ac06o8hm.

但該項目在本地運行時沒有任何問題，指向本地MongoDB數據庫。

例外

2012-05-14T10:17:30+00:00 app[web.1]:
2012-05-14T10:17:30+00:00 app[web.1]: NullPointerException occure
d : null
2012-05-14T10:17:30+00:00 app[web.1]:   at play.mvc.ActionInvoker
.invoke(ActionInvoker.java:231)
2012-05-14T10:17:30+00:00 app[web.1]: play.exceptions.JavaExecuti
onException
2012-05-14T10:17:30+00:00 app[web.1]:   at Invocation.HTTP Reques
t(Play!)
2012-05-14T10:17:30+00:00 app[web.1]:   at com.mongodb.CommandRes
ult.getException(CommandResult.java:64)
2012-05-14T10:17:30+00:00 app[web.1]: Caused by: java.lang.NullPo
interException
2012-05-14T10:17:30+00:00 app[web.1]:   at com.mongodb.DBPort.che
ckAuth(DBPort.java:308)
2012-05-14T10:17:30+00:00 app[web.1]:   at com.mongodb.DBTCPConne
ctor.call(DBTCPConnector.java:201)
2012-05-14T10:17:30+00:00 app[web.1]:   at com.mongodb.CommandRes
ult.throwOnError(CommandResult.java:116)
2012-05-14T10:17:30+00:00 app[web.1]:   at com.mongodb.DBApiLayer
$MyCollection.__find(DBApiLayer.java:303)
2012-05-14T10:17:30+00:00 heroku[router]: GET smooth-lightning-41
34.herokuapp.com/favicon.ico dyno=web.1 queue=0 wait=0ms service=
58ms status=500 bytes=417
2012-05-14T10:17:30+00:00 app[web.1]:   at com.mongodb.DBCursor._
hasNext(DBCursor.java:490)
2012-05-14T10:17:30+00:00 app[web.1]:   at com.mongodb.DBCursor._
check(DBCursor.java:360)
2012-05-14T10:17:30+00:00 app[web.1]:   at com.google.code.morphi
a.query.QueryImpl.asList(QueryImpl.java:255)
2012-05-14T10:17:30+00:00 app[web.1]:   at com.mongodb.DBCursor.h
asNext(DBCursor.java:515)
2012-05-14T10:17:30+00:00 app[web.1]:   at play.modules.morphia.M
odel$MorphiaQuery.asList(Model.java:1320)

UPDATE

-----> Heroku receiving push
-----> Fetching custom buildpack... done
-----> Play! app detected
-----> Installing Play! -.....
-----> Error installing Play! framework or unsupported Play! fram
ework version specified. Please review Dev Center for a list of s
upported versions.
 !     Heroku push rejected, failed to compile Play! app

To git@heroku.com:young-spring-3743.git
 ! [remote rejected] master -> master (pre-receive hook declined)

error: failed to push some refs to 'git@heroku.com:young-spring-3
743.git'

Answer 1

查看日志我可以看到有一個空指針異常，所以下面的一個原因可能是：

1. 傳遞了一個非初始化變量
2. 沒有注冊錯誤
3. 在空集合上有一個方法調用
4. 連接由空請求傳遞

您需要檢查以上所有可能性。