When you extend a class with class Exception ( for creating new exception) you get a warning to have a serialVersionUID. I know that serialVersionUID plays an important role while serialization and deserialization, but when my Exception needs to be serialized? Can anyone give me a practical case in which I want my custom-exception class to have serialization and deserialization?
当您使用类Exception扩展类（用于创建新的异常）时，您会收到一条警告，要求它具有serialVersionUID。我知道serialVersionUID在序列化和反序列化时起着重要的作用，但是当我的Exception需要被序列化时？任何人都可以给我一个实际案例，我希望我的自定义异常类具有序列化和反序列化？
3 个解决方案
#1
51
This is because the root class for all exceptions, Throwable implements the Serializable interface. All exceptions by default are serializable and that's a language design decision because the authors wanted exceptions to be capable of being sent across the wire without any special configuration.
这是因为所有异常的根类，Throwable实现了Serializable接口。默认情况下，所有异常都是可序列化的，这是一种语言设计决策，因为作者希望异常能够在没有任何特殊配置的情况下通过线路发送。
If the base class is not serializable, you would have a difficult time conveying what exactly went wrong in case a remote method failed since you would have no control over the built in exception types.
如果基类不可序列化，那么在远程方法失败的情况下，由于您无法控制内置的异常类型，您将很难传达出现了什么问题。
#2
12
If your custom exception is ever used in a distributed application (using RMI, Spring http-invoker, whatever) and can be thrown from a server method that is invoked from a remote client, then the exception will have to be serialized to cross the wire and go to the client.
如果您的自定义异常曾经在分布式应用程序中使用（使用RMI，Spring http-invoker等）并且可以从远程客户端调用的服务器方法抛出，那么必须将异常序列化以跨越线路并去客户端。
#3
4
Your only options are to either define serialVersionUID for every Exception type you define (the IDE can generate it for you) or suppress the warning.
您唯一的选择是为您定义的每个Exception类型定义serialVersionUID（IDE可以为您生成它）或禁止警告。
You may find my earlier question explicit serialVersionUID considered harmful? relevant.
您可能会发现我之前的问题显式serialVersionUID被认为有害吗？相关。
#1
51
This is because the root class for all exceptions, Throwable implements the Serializable interface. All exceptions by default are serializable and that's a language design decision because the authors wanted exceptions to be capable of being sent across the wire without any special configuration.
这是因为所有异常的根类，Throwable实现了Serializable接口。默认情况下，所有异常都是可序列化的，这是一种语言设计决策，因为作者希望异常能够在没有任何特殊配置的情况下通过线路发送。
If the base class is not serializable, you would have a difficult time conveying what exactly went wrong in case a remote method failed since you would have no control over the built in exception types.
如果基类不可序列化，那么在远程方法失败的情况下，由于您无法控制内置的异常类型，您将很难传达出现了什么问题。
#2
12
If your custom exception is ever used in a distributed application (using RMI, Spring http-invoker, whatever) and can be thrown from a server method that is invoked from a remote client, then the exception will have to be serialized to cross the wire and go to the client.
如果您的自定义异常曾经在分布式应用程序中使用（使用RMI，Spring http-invoker等）并且可以从远程客户端调用的服务器方法抛出，那么必须将异常序列化以跨越线路并去客户端。
#3
4
Your only options are to either define serialVersionUID for every Exception type you define (the IDE can generate it for you) or suppress the warning.
您唯一的选择是为您定义的每个Exception类型定义serialVersionUID（IDE可以为您生成它）或禁止警告。
You may find my earlier question explicit serialVersionUID considered harmful? relevant.
您可能会发现我之前的问题显式serialVersionUID被认为有害吗？相关。