如何在 Java 中处理 NullPointerException
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How to handle NullPointerException in Java
提问by rozer
How to handle NullPointerExceptionin Java? Please provide details so I can get rid of this problem
NullPointerException在Java中如何处理？请提供详细信息，以便我摆脱这个问题
回答by Finbarr
try {
// something stupid
} catch(NullPointerException e) {
// probably don't bother doing clean up
} finally {
// carry on as if nothing went wrong
}
回答by Max Leske
You should really make yourself familiar with the concept of a variable being null. Checkout the API: http://java.sun.com/javase/6/docs/api/java/lang/NullPointerException.html
您真的应该让自己熟悉变量为空的概念。签出API：http: //java.sun.com/javase/6/docs/api/java/lang/NullPointerException.html
Generally, try to do more research in advance.
一般来说，尽量提前做更多的研究。
回答by Daniel Engmann
You should avoid NullPointerExceptions:
您应该避免 NullPointerExceptions：
if(someObject != null) {
someObject.doSomething();
} else {
// do something other
}
Normally you should ensure that the objects which you use are not null.
通常你应该确保你使用的对象不为空。
You also can catch the NullPointerException and except using an if-condition.
您还可以捕获 NullPointerException 并且使用 if 条件除外。
try {
someObject.doSomething();
} catch(NullPointerException e) {
// do something other
}
Normally there is a bug in your code, when a NullPointerException occurs.
通常，当 NullPointerException 发生时，您的代码中存在错误。
