我如何知道空指针异常的起源? [英] How can I know where a Null Pointer Exception originated?

问题描述

我在制作 Blackberry 应用程序时遇到了问题.我找到了一些制作教程的人，该教程完成了我对我的尝试.我复制了教程应用程序的代码以尝试重新创建它，只是为了查看它的运行情况.结果:空指针异常.

I had a problem making a Blackberry app. I found some guy who made a tutorial which did what I attempted with mine. I copied the code of the tutorial's app to try and recreate it, just to see it in action. The result: Null Pointer Exception.

我想知道是什么触发了这个.我该怎么办?

I want to know what is triggering this. How can I?

推荐答案

如果捕获 Throwable 而不是捕获 Exception 或 Exception 的任何子类，则可以查看堆栈跟踪.例如

You can view the stacktrace if you catch Throwable instead of catching Exception or any subclass of Exception. e.g.

try
{
   //some code
}
catch(Throwable t)
{
    //Will automatically show a stacktrace in eclipse.  
    //I believe on a real device it will put the stacktrace in the eventlog.  
}

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